Passive safety system. Vehicle passive safety systems Vehicle active safety elements

13.08.2019

Tuning and extras equipment

Ministry of Education and Science

Russian Federation

State educational institution of higher

vocational education

CONTROL WORK No. 1, No. 2

in the discipline "Safety of vehicles"

Active and passive vehicle safety

Introduction

1 Technical characteristics of the car

2 Active vehicle safety

3 Passive vehicle safety

4 Vehicle environmental friendliness

Conclusion

Literature

INTRODUCTION

A modern car by its nature is a device of increased danger. Taking into account the social significance of the car and its potential danger during operation, manufacturers equip their cars with means that contribute to its safe operation. From the complex of means with which a modern car is equipped, passive safety means are of great interest. The passive safety of the car must ensure the survival and minimization of the number of injuries to the passengers of the car involved in a traffic accident.

In recent years, the passive safety of cars has become one of the most important elements in terms of manufacturers. Huge amounts of money are invested in the study of this topic and its development due to the fact that companies care about the health of customers.

I will try to explain a few definitions hidden under the broad definition of "passive safety".

It is divided into external and internal.

The internal includes measures to protect people sitting in the car through special interior equipment. External passive safety includes measures to protect passengers by giving the body special properties, for example, the absence of sharp corners, deformation.

Passive safety - a set of components and devices that allow you to save the life of car passengers in case of an accident. Includes, among other things:

1.Airbags;

2. crushable or soft elements of the front panel;

3.folding steering column;

4.travmobezopasny pedal assembly - in the event of a collision, the pedals are separated from the attachment points and reduce the risk of damage to the driver's legs;

5.inertial seat belts with pretensioners;

6.energy-absorbing elements of the front and rear parts of the car, crushed upon impact - bumpers;

7.seat headrests - protect the passenger's neck from serious injuries when the car hits from behind;

8.safety glasses: tempered, which, when broken, shatter into many non-sharp fragments and triplex;

9.roll bars, reinforced A-pillars and upper windshield frame in roadsters and convertibles, transverse bars in the doors.

1 Technical characteristics of the car GAZ-66-11

Table 1 - Characteristics of GAS - 66 - 11

Automobile model	GAZ - 66 - 11
Year of issue	1985 - 1996
Dimensional parameters, mm
Length	5805
Width	2322
Height	2520
Base	3300
Track, mm
front wheels	1800
Rear wheels	1750
Weight characteristics
Curb weight, kg	3640
Load capacity, kg	2000
Gross weight, kg	3055
Speed characteristics
Maximum speed, km/h	90
Acceleration time to 100 km/h, sec	no data
Brake mechanisms
front axle	Drum type with internal pads. Diameter 380 mm., width of overlays 80 mm.
rear axle

Table 2. - Values of steady-state deceleration.

2 Active vehicle safety

In scientific terms, this is a set of design and operational properties of a car aimed at preventing traffic accidents and eliminating the prerequisites for their occurrence associated with the design features of the car.

And to put it simply, these are the car systems that help in preventing an accident.

RELIABILITY

The reliability of components, assemblies and vehicle systems is a determining factor in active safety. Particularly high requirements are placed on the reliability of the elements associated with the implementation of the maneuver - the brake system, steering, suspension, engine, transmission, and so on. Increasing the reliability is achieved by improving the design, the use of new technologies and materials.

VEHICLE LAYOUT

The layout of cars is of three types:

a) Front-engine - the layout of the car, in which the engine is located in front of the passenger compartment. It is the most common and has two options: rear-wheel drive (classic) and front-wheel drive. The last type of layout - front-engine front-wheel drive - is now widely used due to a number of advantages over rear-wheel drive:

Better stability and handling when driving at high speed, especially on wet and slippery roads;

Ensuring the necessary weight load on the drive wheels;

Less noise level, which is facilitated by the absence of a cardan shaft.

At the same time, front-wheel drive vehicles have a number of disadvantages:

At full load, acceleration on the rise and on wet roads deteriorates;

At the moment of braking, the distribution of weight between the axles is too uneven (70% -75% of the vehicle's weight falls on the wheels of the front axle) and, accordingly, the braking forces (see Braking properties);

The tires of the front driving steered wheels are loaded more, respectively, more subject to wear;

Front wheel drive requires the use of complex units - constant velocity joints (CV joints)

The combination of the power unit (engine and gearbox) with the final drive complicates access to individual elements.

b) The layout with a central engine - the engine is located between the front and rear axles, for cars is quite rare. It allows you to get the most spacious interior for a given size and a good distribution along the axes.

c) Rear-engined - the engine is located behind the passenger compartment. This arrangement was common in small cars. When transmitting torque to the rear wheels, it made it possible to obtain an inexpensive power unit and distribute such a load along the axles, in which the rear wheels accounted for about 60% of the weight. This had a positive effect on the car's cross-country ability, but negatively on its stability and controllability, especially at high speeds. Cars with this layout, at present, are practically not produced.

BRAKING PROPERTIES

The ability to prevent accidents is most often associated with intensive braking, so it is necessary that the braking properties of the car ensure its effective deceleration in all traffic situations.

To fulfill this condition, the force developed by the brake mechanism must not exceed the traction force, which depends on the weight load on the wheel and the condition of the road surface. Otherwise, the wheel will lock up (stop rotating) and begin to slide, which can lead (especially when several wheels are blocked) to skid the car and significantly increase the braking distance. To prevent blocking, the forces developed by the brake mechanisms must be proportional to the weight load on the wheel. This is realized through the use of more efficient disc brakes.

Modern cars use an anti-lock braking system (ABS) that adjusts the braking force of each wheel and prevents them from slipping.

In winter and summer, the condition of the road surface is different, so for the best realization of the braking properties, it is necessary to use tires that correspond to the season.

TRACTION PROPERTIES

Traction properties (traction dynamics) of the car determine its ability to intensively increase the speed. The confidence of the driver when overtaking, passing through intersections largely depends on these properties. Traction dynamics is especially important for emergency situations when it is too late to brake, difficult conditions do not allow maneuvering, and accidents can be avoided only by getting ahead of the events.

As with braking forces, the traction force on the wheel should not be greater than the traction force, otherwise it will begin to slip. Prevents this traction control system (PBS). When the car accelerates, it slows down the wheel, the rotation speed of which is greater than that of the others, and, if necessary, reduces the power developed by the engine.

VEHICLE STABILITY

Stability - the ability of a car to keep moving along a given trajectory, opposing the forces that cause it to skid and roll over in various road conditions at high speeds.

There are the following types of stability:

Transverse with rectilinear movement (course stability).

Its violation is manifested in the yaw (change of direction) of the car on the road and can be caused by the action of the lateral force of the wind, different values of traction or braking forces on the wheels of the left or right side, their slipping or sliding. large play in steering, incorrect wheel alignment, etc .;

Transverse during curvilinear motion.

Its violation leads to skidding or capsizing under the action of centrifugal force. An increase in the position of the center of mass of the car especially worsens stability (for example, a large mass of cargo on a removable roof rack);

Longitudinal.

Its violation is manifested in the slipping of the drive wheels when overcoming long icy or snowy slopes and the car sliding back. This is especially true for road trains.

DRIVABILITY OF THE VEHICLE

Handling - the ability of the car to move in the direction set by the driver.

One of the characteristics of handling is understeer - the ability of a car to change direction when the steering wheel is stationary. Depending on the change in the turning radius under the influence of lateral forces (centrifugal force on a turn, wind force, etc.), understeer can be:

Insufficient - the car increases the turning radius;

Neutral - the turning radius does not change;

Excessive - the turning radius is reduced.

Distinguish tire and roll understeer.

Tire steering

Tire steering is related to the property of tires to move at an angle to a given direction during side slip (displacement of the contact patch with the road relative to the plane of rotation of the wheel). If you install tires of a different model, the understeer may change and the car will behave differently when cornering when driving at high speed. In addition, the amount of side slip depends on the pressure in the tires, which must correspond to that specified in the vehicle's operating instructions.

Roll Steering

Roll oversteer is due to the fact that when the body tilts (roll), the wheels change their position relative to the road and the car (depending on the type of suspension). For example, if the suspension is double-wishbone, the wheels lean in the direction of the roll, increasing the slip.

INFORMATION

Informativeness - the property of the car to provide the necessary information to the driver and other road users. Insufficient information from other vehicles on the road about the condition of the road surface, etc. often causes accidents. Internal provides the driver with the opportunity to perceive the information necessary to drive the car.

It depends on the following factors:

Visibility should allow the driver to receive all the necessary information about the traffic situation in a timely manner and without interference. Faulty or inefficiently operating washers, windshield and heating systems, windshield wipers, lack of regular rear-view mirrors sharply impair visibility under certain road conditions.

The location of the instrument panel, buttons and control keys, gear lever, etc. should provide the driver with a minimum amount of time to check indications, actions on switches, etc.

External informativeness - providing other road users with information from the car, which is necessary for proper interaction with them. It includes an external light signaling system, a sound signal, dimensions, shape and color of the body. The information content of passenger cars depends on the contrast of their color relative to the road surface. According to statistics, cars painted in black, green, gray and blue are twice as likely to have an accident due to the difficulty of distinguishing them in low visibility conditions and at night. Faulty direction indicators, brake lights, parking lights will not allow other road users to recognize the driver's intentions in time and make the right decision.

COMFORTABILITY

The comfort of the car determines the time during which the driver is able to drive the car without fatigue. An increase in comfort is facilitated by the use of automatic transmission, speed controllers (cruise control), etc. Currently, vehicles are equipped with adaptive cruise control. It not only automatically maintains the speed at a given level, but also, if necessary, reduces it up to a complete stop of the car.

3 Passive vehicle safety

BODY

It provides acceptable loads on the human body from a sharp deceleration in an accident and saves the space of the passenger compartment after the deformation of the body.

In a severe accident, there is a risk that the engine and other components can enter the driver's cab. Therefore, the cabin is surrounded by a special "safety grid", which is an absolute protection in such cases. The same stiffening ribs and bars can be found in the doors of the car (in case of side collisions). This also includes areas of energy repayment.

In a severe accident, there is a sharp and unexpected deceleration to a complete stop of the car. This process causes huge overloads on the bodies of passengers, which can be fatal. It follows from this that it is necessary to find a way to "slow down" the deceleration in order to reduce the load on the human body. One way to solve this problem is to design areas of destruction that dampen the energy of a collision in the front and rear parts of the body. The destruction of the car will be more severe, but the passengers will remain intact (and this is compared to the old "thick-skinned" cars, when the car got off with a "light fright", but the passengers received severe injuries).

The design of the body provides that in the event of a collision, the parts of the body are deformed, as it were, separately. Plus, high-tensioned metal sheets are used in the design. This makes the car more rigid, and on the other hand allows it to be not so heavy.

SEAT BELTS

At first, cars were equipped with two-point belts that “held” riders by the stomach or chest. In less than half a century, engineers realized that the multi-point design is much better, because in the event of an accident it allows you to distribute the pressure of the belt on the surface of the body more evenly and significantly reduce the risk of injury to the spine and internal organs. In motorsport, for example, four-, five- and even six-point seat belts are used - they keep the person in the seat “tightly”. But on the “citizen”, because of their simplicity and convenience, three-point ones took root.

In order for the belt to work properly for its purpose, it must fit snugly against the body. Previously, belts had to be adjusted, adjusted to fit. With the advent of inertial belts, the need for “manual adjustment” has disappeared - in the normal state, the coil rotates freely, and the belt can wrap around a passenger of any build, it does not hinder actions, and every time a passenger wants to change the position of the body, the strap always fits snugly to the body. But at the moment when “force majeure” comes, the inertial coil will immediately fix the belt. In addition, on modern machines, squibs are used in belts. Small explosive charges detonate, pulling the belt, and he presses the passenger to the back of the seat, preventing him from hitting.

Seat belts are one of the most effective means of protection in an accident.

Therefore, passenger cars must be equipped with seat belts if attachment points are provided for this. The protective properties of belts largely depend on their technical condition. Belt malfunctions, in which the vehicle is not allowed to be operated, include tears and abrasions of the fabric tape of the straps visible to the naked eye, unreliable fixation of the tongue of the strap in the lock or the absence of automatic ejection of the tongue when the lock is unlocked. For inertia-type seat belts, the webbing should be freely retracted into the reel and blocked when the car is moving sharply at a speed of 15-20 km / h. Belts that have experienced critical loads during an accident in which the car body has received serious damage are subject to replacement.

AIRBAGS

One of the most common and effective safety systems in modern cars (after seat belts) are airbags. They began to be widely used already in the late 70s, but it was not until a decade later that they really took their rightful place in the safety systems of most manufacturers' cars.

They are located not only in front of the driver, but also in front of the front passenger, as well as from the sides (in the doors, pillars, etc.). Some car models have their forced shutdown due to the fact that people with heart problems and children may not be able to withstand their false operation.

Today, airbags are commonplace not only in expensive cars, but also in small (and relatively inexpensive) cars. Why are airbags needed? And what are they?

Airbags have been developed for both drivers and front seat passengers. For the driver, the pillow is usually installed on the steering, for the passenger - on the dashboard (depending on the design).

The front airbags are deployed when an alarm is received from the control unit. Depending on the design, the degree of filling of the pillow with gas may vary. The purpose of the front airbags is to protect the driver and passenger from injury by solid objects (engine body, etc.) and glass fragments in frontal collisions.

Side airbags are designed to reduce damage to vehicle occupants in a side impact. They are installed on the doors or in the backs of the seats. In the event of a side impact, external sensors send signals to the central airbag control unit. This makes it possible for some or all of the side airbags to deploy.

Here is a diagram of how the airbag system works:

Studies of the effect of airbags on the likelihood of driver death in frontal collisions have shown that it is reduced by 20-25%.

If the airbags have deployed or been damaged in any way, they cannot be repaired. The entire airbag system must be replaced.

The driver's airbag has a volume of 60 to 80 liters, and the front passenger - up to 130 liters. It is easy to imagine that when the system is triggered, the interior volume decreases by 200-250 liters within 0.04 seconds (see figure), which gives a considerable load on the eardrums. In addition, a pillow flying at a speed of more than 300 km / h is fraught with a considerable danger to people if they are not fastened with a seat belt and nothing delays the inertial movement of the body towards the pillow.

There are statistics on the impact of airbags on injuries in an accident. What can be done to reduce the chance of injury?

If your car has an airbag, do not place rear-facing child seats on a vehicle seat where the airbag is located. When inflated, the airbag may move the seat and cause injury to the child.

Airbags in the passenger seat increase the risk of death for children under the age of 13 sitting in that seat. A child less than 150 cm tall can be hit in the head by an air bag that opens at a speed of 322 km/h.

HEADRESTS

The role of the head restraint is to prevent sudden movement of the head during an accident. Therefore, you should adjust the height of the head restraint and its position to the correct position. Modern head restraints have two degrees of adjustment to prevent injuries to the cervical vertebrae during the “overlapping” movement, which are so characteristic of rear-end collisions.

Effective protection when using a head restraint can be achieved if it is located exactly on the center line of the head at the level of its center of gravity and no more than 7 cm from the back of it. Be aware that some seat options change the size and position of the head restraint.

SAFETY STEERING GEAR

Crash-safe steering is one of the constructive measures that ensure the passive safety of the car - the ability to reduce the severity of the consequences of traffic accidents. The steering gear can cause serious injury to the driver in a frontal collision with an obstacle when the front of the vehicle is crushed when the entire steering gear moves towards the driver.

The driver can also be injured from the steering wheel or steering shaft when moving forward sharply due to a frontal collision, when the movement is 300 ... 400 mm with a weak seat belt tension. To reduce the severity of injuries sustained by the driver in frontal collisions, which account for about 50% of all traffic accidents, various designs of safety steering mechanisms are used. To this end, in addition to the steering wheel with a recessed hub and two spokes, which can significantly reduce the severity of injuries on impact, a special energy-absorbing device is installed in the steering mechanism, and the steering shaft is often made composite. All this provides a slight movement of the steering shaft inside the car body in frontal collisions with obstacles, cars and other vehicles.

Other energy-absorbing devices that connect composite steering shafts are also used in safety steering controls of passenger cars. These include rubber couplings of a special design, as well as devices of the "Japanese flashlight" type, which is made in the form of several longitudinal plates welded to the ends of the connected parts of the steering shaft. In collisions, the rubber clutch is destroyed, and the connecting plates are deformed and reduce the movement of the steering shaft inside the body.

The main elements of a wheel assembly are a rim with a disk and a pneumatic tire, which can be tubeless or consist of a tire, a tube and a rim tape.

EMERGENCY EXITS

Roof hatches and windows of buses can be used as emergency exits for quick evacuation of passengers from the passenger compartment in case of an accident or fire. For this purpose, inside and outside the passenger compartment of buses, special means are provided for opening emergency windows and hatches. So, glasses can be installed in the window openings of the body on two locking rubber profiles with a locking cord. In case of danger, it is necessary to pull out the lock cord using the bracket attached to it, and squeeze out the glass. Some windows are hung in the opening on hinges and are provided with handles for opening them outward.

Devices for actuating the emergency exits of buses in service must be in working order. However, during the operation of buses, ATP employees often remove the bracket on emergency windows, fearing deliberate damage to the window seal by passengers or pedestrians in cases where this is not dictated by necessity. Such "prudence" makes it impossible for emergency evacuation of people from buses.

4 Vehicle environmental friendliness

Environmental Safety- this is a property of the car, which allows to reduce the harm caused to road users and the environment during its normal operation. Measures to reduce the harmful effects of vehicles on the environment should be considered to reduce the toxicity of exhaust gases and noise levels.

The main pollutants during the operation of vehicles are:

- traffic fumes;

– oil products during their evaporation;

– abrasion products of tires, brake pads and clutch discs, asphalt and concrete surfaces.

The main measures to prevent and reduce the harmful effects of vehicles on the environment should be considered:

1) the development of such car designs that would pollute the atmospheric air less with toxic components of exhaust gases and would create noise at a lower level;

2) improving the methods of repair, maintenance and operation of vehicles in order to reduce the concentration of toxic components in exhaust gases, the level of noise produced by vehicles, and environmental pollution with operating materials;

3) compliance in the design and construction of roads, engineering structures, service facilities with such requirements as fitting an object into the landscape; a rational combination of elements of the plan and the longitudinal profile, ensuring the constancy of the speed of the car; protection of surface and ground waters from pollution; water and wind erosion control; prevention of landslides and collapses; conservation of flora and fauna; reduction of areas allocated for construction; protection of buildings and structures near the road from vibrations; combating traffic noise and air pollution; application of construction methods and technologies that bring the least damage to the environment;

4) the use of means and methods of organizing and regulating traffic, providing optimal traffic modes and characteristics of traffic flows, reducing stops at traffic lights, the number of gear changes and the time of operation of engines in unsteady modes.

Vehicle Noise Reduction Methods

To reduce the noise of the car, first of all, they strive to design less noisy mechanical components; reduce the number of processes accompanied by shocks; reduce the magnitude of unbalanced forces, the speed of flow around parts with gas jets, the tolerances of mating parts; improve lubrication; use plain bearings and noiseless materials. In addition, the reduction of vehicle noise is achieved by the use of noise-absorbing and noise-isolating devices.

Noise in the intake tract of the engine can be reduced with the help of a specially designed air cleaner with resonant and expansion chambers, and inlet pipe designs that reduce the speed of the air-fuel mixture flow around the internal surfaces. These devices allow you to reduce the intake noise level by 10-15 dB A-weighted.

Noise level, when exhaust gases are released(when they flow through the exhaust valves), can reach 120–130 dB on the A scale. To reduce exhaust noise, active or reactive silencers are installed. The most common simple and cheap active silencers are multi-chamber channels, the inner walls of which are made of sound-absorbing materials. The sound is damped as a result of the friction of the exhaust gases against the inner walls. The longer the muffler and the smaller the cross section of the channels, the more intense the sound is damped.

Jet silencers are a combination of elements of different acoustic elasticity; noise reduction in them occurs due to repeated reflection of sound and its return to the source. It should be remembered that the more efficient the muffler works, the more the effective engine power decreases. These losses can reach 15% or more. During the operation of vehicles, it is necessary to carefully monitor the serviceability (primarily tightness) of the intake and exhaust tracts. Even a small depressurization of the muffler dramatically increases the exhaust noise. Noise in the transmission, chassis and bodywork of a new serviceable vehicle can be reduced through design improvements. The gearbox uses synchronizers, helical gears of constant mesh, blocking tapered rings and a number of other design solutions. Intermediate propeller shaft supports, hypoid main gears, and less noisy bearings are gaining popularity. Improved suspension elements. In the structures of bodies and cabs, welding, noise-insulating gaskets and coatings are widely used. Noise in the above parts and mechanisms of cars can occur and reach significant values only in case of malfunctions of individual components and parts: breakage of the gear teeth, warpage of the clutch discs, imbalance of the cardan shaft, violation of the gaps between the gears in the main gear, etc. The noise of the car increases especially sharply in case of malfunction of various elements of the body. The main way to eliminate noise is the correct technical operation of the car.

CONCLUSION

Ensuring the good condition of the structural elements of the car, the requirements for which were considered earlier, can reduce the likelihood of an accident. However, it has not yet been possible to create absolute safety on the roads. That is why experts in many countries pay great attention to the so-called passive car safety, which allows to reduce the severity of the consequences of an accident.

LITERATURE

1. www.anytyres.ru

2. www.transserver.ru

3. Theory and design of the car and engine

Vakhlamov V.K., Shatrov M.G., Yurchevsky A.A.

4. Organization of road transport and traffic safety 6 studies. allowance for students of higher education. institutions / A.E. Gorev, E.M. Oleshchenko .- M .: Publishing Center "Academy". 2006.(p.187-190)

In such a complex unit as a car, it is very easy to forget about one of the most basic systems - the protection and safety system. And if active safety is always covered in detail both by the media and by the dealers or sellers themselves, then passive safety is nothing more than a gray mouse inside the complex structure of a vehicle.

What is passive car safety

Passive safety- this is a set of properties and adaptations of the vehicle, which have their own unique design and operational differences, but are functionally aimed at ensuring the safest possible conditions in case of an accident. Unlike an active safety system, the action of which is aimed at saving the car from accidents, the car's passive safety system is activated after the accident has taken place.

In order to reduce the consequences of an accident, a whole set of devices is used, the purpose of which is to reduce the severity of an accident. For a more accurate classification, a division into two main groups is used:

internal system - it includes:

Airbags
Seat belts
Seat structure (headrests, armrests, etc.)
Body energy absorbers
Other soft interior elements

External system - Another, no less important group, is presented in the form:

Bumpers
Protrusions on the body
glasses
rack amplifiers

Recently, on the pages of well-known news agencies, they began to cover in detail the points that report on all the elements of passive safety in a car. In addition, we should not forget the activities of the independent organization Euro NCAP (European New Car Assessment Program). This committee has been crash-testing all models entering the market for quite some time now, awarding test reports for both active and passive safety systems. Anyone can get acquainted with the data on the results of crash tests, making sure of each of the components of the protection system.

The image shows how all passive safety systems work harmoniously during an emergency (seat belts, airbags, seat with headrest).

Internal passive safety

All passive safety elements included in this list are designed to protect everyone in the passenger compartment of a car that has had an accident. That is why, in addition to equipping the car with special equipment (in good condition), it is very important that it be used by all participants in the ride for its intended purpose. Only compliance with all the rules will allow you to get the highest protection. Next, we will consider the most basic items that are included in the list of internal passive safety.

The body is the basis of the entire security system. The strength of the car and the possible deformation of its parts directly depend on the material, condition, and design features of the car body. To protect passengers from getting under the hood contents into the cabin, the designers specifically use a "safety grill" - a strong layer that does not allow breaking the cabin base.
Interior safety from structural elements is a whole list of devices and technologies that are designed to protect the health of the driver and passengers. For example, many salons provide for a folding steering wheel that does not allow additional damage to the driver. In addition, modern cars are equipped with a safety pedal assembly, the action of which provides for the detachment of the pedals from the mounts, reducing the load on the lower limbs.

To count on maximum safety during the use of the head restraint, you must very clearly set its position to a certain height that suits you.

Seat belts - from the accepted standard of lap 2-point belts, which held the passenger with a conventional tie through the stomach or chest, they refused back in the middle of the last century. Such passive safety features required improvements, which came in the form of multi-point harnesses. The increased functionality of this type of device made it possible to evenly distribute the kinetics throughout the body without traumatizing individual areas of the body.
Airbags are the second most important (seat belts confidently hold the first line here), a passive safety system. Recognized in the late 70s. they are tightly integrated into all vehicles. The modern auto industry began to be equipped with a whole set of airbag systems that surround the driver and passengers from all sides, blocking potential damage zones. The sharp opening of the chamber with the storage of the pillow activates the rapid filling with the last air mixture, which cushions the person approaching by inertia.
Seats and Headrests - The seat itself does not offer additional functions during a crash other than to hold the passenger in place. However, the head restraints, on the contrary, reveal their functionality just at the moment of collision, preventing the head from tilting back with subsequent trauma to the cervical vertebrae.
Other internal passive safety features - many vehicles are provided with highly stressed metal sheets. Such an upgrade allows you to make the car more impact-resistant, while reducing its weight. Many cars also use an active system of destruction areas, which dampen the resulting kinetics in a collision, and are themselves destroyed in the process (increased destruction of a car is nothing compared to human life and health).

On the example of the frame of a small Smart car body, one can see how passive safety plays a fundamental role even at the design stage of a future car.

External passive safety

If in the previous paragraph we considered the means and devices of a car that protect passengers and drivers at the time of an accident, then this time we will talk about a complex that allows you to maximally protect the health of a pedestrian who has fallen under the wheels of the car in question.

Bumpers - the design of modern bumpers includes several energy- and kinetic-absorbing elements that are present both at the front of the car and at the rear. Their purpose is to absorb the energy arising from the impact due to blocks prone to crushing. This not only reduces the risk of damage to a pedestrian, but also greatly reduces damage inside the car.
External protrusions of cars - as a rule, it is difficult to attribute to the useful properties of such elements. However, as it may seem at first glance, most of these elements have a similar principle of self-destruction, described earlier in paragraph 6. of the section "Internal passive safety".
Devices for the protection of pedestrians - individual manufacturing companies represented by Bosch, Siemens, TRW and others, have been actively developing systems for providing additional safety to pedestrians involved in an accident for several decades. For example, the Electronic Pedestrian Protection system will allow you to raise the roof of the hood, increasing the area of \u200b\u200bit collision with the body of a pedestrian, while acting as a "shield" from the harder and uneven parts of the engine compartment.

Active safety of a car is a combination of its design and operational properties aimed at preventing and reducing the likelihood of an accident on the road.

Table 1.1 - Vehicle active safety systems

System name

System description

Anti-Lock Braking System

This is a system that prevents the car's wheels from locking when braking. Its main purpose is to prevent loss of control of the vehicle during heavy braking, as well as to avoid slipping the car.

The ABS system significantly reduces the braking distance and allows the driver to maintain control over the car during emergency braking, that is, with this system, it becomes possible to make sharp maneuvers during braking. Now ABS can also include traction control, electronic stability control and emergency braking assistance. In addition to cars, ABS is also installed on motorcycles, trailers and wheeled chassis of aircraft.

Continuation of table 1.1

Traction Control (Traction Control,Traction Control System)

Designed to eliminate the loss of traction of the wheels with the road by controlling the slipping of the drive wheels.

APS greatly simplifies driving on wet roads or in other conditions of insufficient grip.

Electronic Stability Control (Stability Program)

This is an active safety system that allows you to prevent the car from skidding by controlling the moment of force of the wheel (simultaneously one or more) by the computer. It is an auxiliary system of the car.

This system stabilizes the movement in dangerous situations, when loss of vehicle control is likely or has already occurred. The ESC is one of the most effective vehicle safety systems.

Brake force distribution system

This system is a continuation of the ABS (Anti-Lock Braking System). It differs in that it helps the driver to drive the car constantly, and not only in case of emergency braking. Since the degree of grip of the wheels with the road is different, and the braking force transmitted to the wheels is the same, the brake force distribution system helps the car maintain stability when braking by analyzing the position of each

Continuation of table 1.1

wheels and dosing the braking force on it.

Electronic differential lock

First of all, the differential is necessary to transmit torque from the gearbox to the wheels of the drive axle. It works when the drive wheels are firmly attached to the road. But, in situations where one of the wheels is in the air or on ice, it is this wheel that rotates, while the other, standing on a hard surface, loses all power.

The differential lock is necessary to transmit torque to both of its consumers (half shafts or cardan shafts).

In addition to the above active vehicle safety systems, there are also auxiliary systems. These include:

Parktronic (Parking radar, Acoustic Parking System, Ultrasonic parking sensor). The system uses ultrasonic sensors to measure the distance from the vehicle to nearby objects. If the car is parked at a "dangerous" distance from obstacles, the system emits a warning sound or displays information about the distance on the display;

Adaptive cruise control Cruise control is a device that maintains a constant vehicle speed, automatically increasing it when the speed is reduced and decreasing the speed when it increases;

Descent assistance system;

Assistance system when lifting;

Parking brake (Handbrake, handbrake) - a system that is designed to keep the car stationary relative to the supporting surface. The handbrake helps with braking the car in parking lots and keeping it on slopes.

Safety depends on three important characteristics of a vehicle: size and weight, passive safety features that help you survive crashes and avoid injury, and active safety features that help you avoid crashes.
However, in a collision, heavier cars with relatively poor crash test scores may perform better than lighter cars with excellent crash test scores. Twice as many people die in compact and small cars as in large ones. This should always be remembered.

Passive safety equipment helps the driver and passengers to survive in an accident and remain without serious injury. The size of the car is also a means of passive safety: bigger = safer. But there are other important points as well.

Seat belts became the best occupant protection device ever invented. The sound idea of tying a person to a seat to save his life in an accident dates back to 1907. Then the driver and passengers were fastened only at waist level. The first production car belts were supplied by the Swedish company Volvo in 1959. The belts in most cars are three-point, inertia, in some sports cars, four-point and even five-point are used to better keep the driver in the saddle. One thing is clear: the tighter you are pressed to the chair, the safer. Modern seat-belt systems have automatic pretensioners that, in the event of an accident, take up the slack in the belts, increasing occupant protection and saving room for the airbags to deploy. It is important to know that although airbags protect against serious injury, seat belts are absolutely essential for the overall safety of the driver and passengers. The American traffic safety organization NHTSA, based on its research, reports that the use of seat belts reduces the risk of death by 45-60%, depending on the type of car.

Without airbags in a car it’s impossible, only the lazy one doesn’t know this now. They will save us both from a blow and from broken glass. But the first pillows were like an armor-piercing projectile - they opened up under the influence of impact sensors and fired towards the body at a speed of 300 km / h. Attraction for survival, and only, not to mention the horror that a person experienced at the time of the cotton. Now pillows are found even in the cheapest cars and can open at different speeds depending on the strength of the collision. The device has gone through many modifications and has been saving lives for 25 years. However, the danger still remains. If you forgot or were too lazy to buckle up, then the pillow can easily ... kill. During an accident, even at low speed, the body flies forward by inertia, the airbag that opens will stop it, but the head will kick back with great speed. In surgeons, this is called a “whiplash injury”. In most cases, this threatens to fracture the cervical vertebrae. At best, eternal friendship with vertebroneurologists. These are doctors who sometimes manage to put your vertebrae in place. But, as you know, it is better not to touch the cervical vertebrae, they are classified as untouchable. That is why in many cars a nasty squeak is heard, which does not so much remind us that we need to buckle up, but tells us that the airbag will NOT open if the person is not buckled up. Listen carefully to what your car is singing to you. Airbags are designed specifically to work with seat belts and are by no means a substitute for their use. According to the American organization NHTSA, the use of airbags reduces the risk of death in an accident by 30-35%, depending on the type of car.
During a collision, the seat belts and airbags work together. The combination of their work is 75% more effective in preventing serious head injuries and 66% more effective in preventing chest injuries. Side airbags also significantly improve the protection of the driver and passengers. Auto manufacturers also use dual-stage airbags that inflate one after the other in stages to avoid potential injury to children and small adults from single-stage, cheaper airbags. In this regard, it is more correct to put children only in the rear seats in cars of any type.

Headrests are designed to prevent injury from sudden, violent movement of the head and neck in a rear-end collision. In fact, often head restraints provide little or no protection against injury. Effective protection when using a head restraint can be achieved if it is located exactly on the center line of the head at the level of its center of gravity and no more than 7 cm from the back of it. Be aware that some seat options change the size and position of the head restraint. Significantly increase safety active head restraints. The principle of their work is based on simple physical laws, according to which the head leans back a little later than the body. Active head restraints use body pressure on the seatback at the time of impact to cause the head restraint to move up and forward, preventing injury-causing head-back movement. When hitting the rear of the car, the new head restraints act simultaneously with the seat back to reduce the risk of injury to the vertebrae not only of the cervical, but also of the lumbar. After the impact, the lower back of the person sitting in the chair involuntarily moves deep into the backrest, while the built-in sensors give the “command” to the headrest to move forward and upward in order to evenly distribute the load on the spine. Extending upon impact, the headrest securely fixes the back of the head, preventing excessive bending of the cervical vertebrae. Bench tests have shown that the new system is 10-20% more efficient than the existing one. In this case, however, much depends on the position in which the person is at the moment of impact, his weight, and whether he is wearing a seat belt.

Structural integrity(carcass integrity) is another important component of the car's passive safety. For each car, it is tested before going into production. The carcass parts must not change their shape upon impact, while other parts must absorb the impact energy. Crumple zones in front and behind have become, perhaps, the most serious achievement here. The better the hood and trunk will crumple, the less passengers will get. The main thing is that the engine should go to the floor during an accident. Engineers are developing more and more combinations of materials to absorb impact energy. The results of their activities can be very clearly seen in the horror stories of crash tests. Between the hood and the trunk, as you know, there is a salon. So he should become a safety capsule. And this rigid frame should never collapse. The strength of the rigid capsule makes it possible to survive even in the smallest car. If the front and rear frame is protected by a hood and trunk, then only metal bars in the doors are responsible for our safety on the sides. With the worst impact, a side impact, they cannot protect, so they use active systems here - side airbags and curtains, which also look after our interests.

Also, the elements of passive safety include:
-front bumper, absorbing part of the kinetic energy in a collision;
- safety details of the interior of the passenger compartment.

Active vehicle safety

In the arsenal of active car safety, there are many anti-crash systems. Among them are old systems and newfangled inventions. To name just a few: Anti-Lock Braking System (ABS), traction control, electronic stability control (ESC), night vision and automatic cruise control are the latest technologies that help drivers on the road today.

Anti-Lock Braking System (ABS) helps to stop faster and not lose control of the car, especially on slippery surfaces. In the event of an emergency stop, ABS works differently than conventional brakes. With conventional brakes, a sudden stop often causes the wheels to lock up, causing a skid. The anti-lock braking system detects when the wheel is locked and releases it, applying the brakes 10 times faster than the driver can. When the ABS is activated, a characteristic sound is heard and vibration is felt on the brake pedal. To use ABS effectively, you need to change your braking technique. It is not necessary to release and depress the brake pedal again as this disables the ABS system. In the event of emergency braking, press the pedal once and gently hold it until the vehicle stops.

Traction Control (TCS) It is used to prevent slipping of the drive wheels, regardless of the degree of pressing the gas pedal and the road surface. Its principle of operation is based on a decrease in engine output power with increasing speed
driving wheels. The computer controlling this system learns about the frequency of rotation of each wheel from the sensors installed at each wheel and from the acceleration sensor. Exactly the same sensors are used in ABS systems and torque control systems.
moment, so often these systems are used simultaneously. According to the signals of the sensors indicating that the drive wheels are starting to slip, the computer decides to reduce the engine power and has an effect on it similar to
a decrease in the degree of pressing the gas pedal, and the degree of gas discharge is the stronger, the higher the rate of increase in slippage.

ESC (electronic stability control)- she is ESP. The task of the ESC is to maintain the stability and controllability of the car in the extreme cornering modes. By monitoring the vehicle's lateral accelerations, steering vector, braking force and individual wheel speeds, the system detects situations that threaten to skid or roll over, and automatically release the gas and brake the corresponding wheels. The figure clearly illustrates the situation when the driver has exceeded the maximum speed of entry into a turn, and a skid (or drift) has begun. The red line is the trajectory of the car without ESC. If her driver starts to slow down, he has a serious chance to turn around, and if not, then fly off the road. ESC, on the other hand, will selectively slow down the desired wheels so that the car remains on the desired trajectory. ESC is the most sophisticated device that cooperates with anti-lock braking (ABS) and traction control (TCS) systems, controls traction and throttle control. The ESC system on a modern car is almost always disabled. This can help in unusual situations on the road, such as rocking a stuck car.

Cruise control- this is a system that automatically maintains a given speed, regardless of changes in the road profile (ascents, descents). The operation of this system (fixing the speed, its decrease or increase) is carried out by the driver by pressing the buttons on the steering column switch or steering wheel after the vehicle has accelerated to the required speed. When the driver presses the brake or accelerator pedal, the system is instantly disengaged. Cruise control significantly reduces the appearance of driver fatigue on long journeys, as it allows the person's legs to be in a relaxed state. In most cases, cruise control reduces fuel consumption because the engine is kept stable; the motor resource of the engine increases, since at constant revolutions supported by the system there are no variable loads on its parts.

In addition to maintaining a constant speed, it simultaneously monitors compliance with a safe distance from the vehicle in front. The main element of active cruise control is an ultrasonic sensor installed in the front bumper or behind the grille. Its principle of operation is similar to parking radar sensors, only the range is several hundred meters, and the coverage angle, on the contrary, is limited to several degrees. By sending an ultrasonic signal, the sensor waits for a response. If the beam found an obstacle in the form of a car moving at a lower speed and returned, then it is necessary to reduce the speed. As soon as the road is free again, the car accelerates to its original speed.

Tires are one of the important safety features of a modern car. Consider: they are the only thing that connects the car to the road. A good set of tires gives a big advantage in how the car reacts to emergency maneuvers. The quality of tires also significantly affects the handling of cars.

Consider, for example, the equipment of the Mercedes S-class. In the basic configuration of the car there is a Pre-Safe system. When an accident is imminent, which the electronics determines by hard braking or too much wheel slip, Pre-Safe tightens the seat belts and inflates
airbags in the multi-contour front and rear seats to better lock in passengers. In addition, Pre-Safe "battens down the hatches" - closes the windows and the sunroof. All these preparations should reduce the severity of a possible accident. All kinds of electronic driver assistants make the S-class excellent in emergency training - the ESP stabilization system, the ASR traction control system, the Brake Assist emergency braking system. The emergency braking assistance system in the S-Class is combined with the radar. Radar determines
distance from vehicles in front.

If it becomes dangerously short, and the driver brakes weaker than necessary, the electronics begin to help him. During emergency braking, the vehicle's brake lights flash. On request, the S-Class can be equipped with the Distronic Plus system. It is an automatic cruise control, very handy in traffic jams. The device, using the same radar, controls the distance to the car in front, stops the car if necessary, and when the flow resumes movement, it automatically accelerates it to its previous speed. Thus, Mercedes saves the driver from any manipulation other than turning the steering wheel. Distronic works
at speeds from 0 to 200 km/h. The parade of anti-crash devices of the S-class is completed by an infrared night vision system. She snatches out of the darkness objects hidden from powerful xenon headlights.

Car safety rating (EuroNCAP crash tests)

The main light of passive safety is the "European New Car Testing Association", or "EuroNCAP" for short. Founded in 1995, this organization is committed to regularly destroying brand new cars, giving ratings on a five-star scale. The more stars, the better. So, if safety is your top priority when choosing a new car, go for a model that has received the highest possible five-star rating from EuroNCAP.

All series of tests pass according to one scenario. First, the organizers select cars of one class and one model year that are popular on the market and anonymously buy two cars of each model. Tests are carried out at two well-known independent research centers - the English TRL and the Dutch TNO. From the first tests in 1996 until mid-2000, the EuroNCAP safety rating was "four-star" and included an assessment of the car's behavior in two types of tests - frontal and side crash tests.

But in the summer of 2000, EuroNCAP experts introduced another, additional, test - an imitation of a side impact on a pole. The car is placed transversely on a movable trolley and at a speed of 29 km / h is directed by the driver's door into a metal pillar with a diameter of about 25 cm. Only those cars that are equipped with special head protection for the driver and passengers - "high" side airbags or inflatable "curtains" pass this test. ".

If the car passes three tests, a star-shaped halo appears around the head of the dummy on the side impact safety icon. If the halo is green, it means that the car has successfully passed the third test and received additional points that can move it to the five-star category. And those cars that do not have “high” side pillows or inflatable “curtains” as standard equipment are tested according to the usual program and cannot qualify for the highest Euro-NCAP rating.
It turned out that effectively working protective devices can reduce the risk of head injuries in the event of a side impact on a pole by more than an order of magnitude. For example, without “high” pillows or “curtains”, the head injury probability coefficient HIC (Head Injury Criteria) in the “pillar” test can reach 10,000! (The threshold value of HIC, beyond which the area of deadly head injuries begins, is considered by doctors to be 1000.) But with the use of “high” pillows and “curtains”, HIC drops to safe values - 200-300.

The pedestrian is the most vulnerable road user. However, EuroNCAP took care of its safety only in 2002, having developed an appropriate methodology for evaluating cars (green stars). Having studied the statistics, the experts came to the conclusion that the majority of pedestrian collisions occur according to one scenario. First, the car hits the legs with a bumper, and then the person, depending on the speed of movement and the design of the car, hits his head either on the hood or on the windshield.

Prior to the test, the bumper and front edge of the hood are drawn into 12 sections, and the hood and bottom of the windshield are divided into 48 sections. Then successively each section is hit with imitators of the legs and head. The impact force corresponds to a collision with a person at a speed of 40 km / h. Sensors are placed inside the simulators. After processing their data, the computer assigns a specific color to each marked area. Green indicates the safest areas, red - the most dangerous, yellow - occupying an intermediate position. Then, according to the totality of ratings, an overall “star” rating is given to the car for pedestrian safety. The maximum possible score is four stars.

In recent years, a clear trend has been observed - more and more new cars receive "stars" in the pedestrian test. Only large off-road vehicles remain problematic. The reason is in the high front part, because of which, in the event of a collision, the blow falls not on the legs, but on the torso.

And one more innovation. More and more cars are equipped with Seat Belt Reminders (SBR) - for the presence of such a system in the driver's seat, EuroNCAP experts award one additional point, for equipping both front seats - two points.

The American National Highway Traffic Safety Association (NHTSA) conducts crash tests using its own methodology. In a frontal impact, the car crashes into a rigid concrete barrier at a speed of 50 km/h. More severe and side impact conditions. The trolley weighs almost 1400 kg and the car is moving at a speed of 61 km/h. Such a test is carried out twice - blows are made to the front door, and then to the back door. In the United States, another organization professionally and officially beats cars - the Institute for Transportation Research for Insurance Companies IIHS. But its methodology is not significantly different from the European one.

Factory crash tests

It is clear even to a non-specialist that the tests described above do not cover all possible types of accidents and, therefore, do not allow a sufficient assessment of the safety of the car. Therefore, all major automakers conduct their own, non-standard, crash tests, sparing neither time nor money. For example, each new Mercedes model undergoes 28 tests before production starts. On average, one test takes about 300 man-hours. Some of the tests are carried out virtually, on a computer. But they play an auxiliary role, for the final refinement of cars they are broken only in “real life”. The most severe consequences occur as a result of head-on collisions. Therefore, the main part of the factory tests imitates this type of accident. In this case, the car is crashed into deformable and rigid obstacles at different angles, with different speeds and different overlap sizes. However, such tests do not give the whole picture. Manufacturers began to push cars together, not only "classmates", but also cars of different "weight categories" and even cars with trucks. Thanks to the results of such tests, underrun protection beams have become mandatory on all trucks since 2003.

The factory safety specialists also approach the side impact tests with ingenuity. Different angles, speeds, places of impacts, equal-sized and different-sized participants - everything is the same as with frontal tests.

Convertibles and large off-road vehicles are also tested for a coup, because according to statistics, the death toll in such accidents reaches 40%

Manufacturers often test their cars with a rear impact at low speeds (15-45 km/h) and up to 40% overlap. This allows you to assess how protected passengers are from whiplash (damage to the cervical vertebrae) and how protected the gas tank is. Frontal and side impacts at speeds up to 15 km/h help determine the extent of damage (i.e. repair costs) in minor accidents. Seats and seat belts are subjected to separate tests.

What are car manufacturers doing to protect pedestrians? The bumper is made of softer plastic, and as few reinforcing elements as possible are used in the hood design. But the main danger to human life is engine compartment units. When hitting the head misses the hood and stumbles on them. Here they go in two ways - they try to maximize the free space under the hood, or they supply the hood with squibs. A sensor located in the bumper, upon impact, sends a signal to the mechanism that triggers the squib. The latter, firing, raises the hood by 5-6 centimeters, thereby protecting the head from hitting the hard ledges of the engine compartment.

adult dolls

Everyone knows that dummies are used to conduct crash tests. But not everyone knows that such a seemingly simple and logical decision was not reached immediately. At the beginning, human corpses, animals were used for testing, and living people, volunteers, participated in less dangerous tests.

The pioneers in the fight for human safety in the car were the Americans. It was in the USA that the first mannequin was made back in 1949. According to his "kinematics" he looked more like a big doll: his limbs did not move at all like a person's, and his body was solid. It wasn't until 1971 that GM created a more or less "humanoid" mannequin. And modern "dolls" differ from their ancestor, approximately like a person from a monkey.

Now mannequins are made by whole families: two versions of the "father" of different height and weight, a lighter and smaller "wife" and a whole set of "children" - from one and a half to ten years of age. The weight and proportions of the body completely imitate the human. Metal "cartilage" and "vertebrae" work like a human spine. Flexible plates replace the ribs, and hinges replace the joints, even the feet are mobile. From above, this "skeleton" is covered with a vinyl coating, the elasticity of which corresponds to the elasticity of human skin.

Inside, the mannequin is stuffed from head to toe with sensors that, during tests, transmit data to a memory unit located in the “thorax”. As a result, the cost of the mannequin is - hold on to the chair - over 200 thousand dollars. That is, several times more expensive than the vast majority of the tested cars! But such "dolls" are universal. Unlike their predecessors, they are suitable for both frontal and side tests, and rear-end collisions. Preparing the dummy for testing requires fine-tuning of the electronics and can take several weeks. In addition, just before the test, paint marks are applied to various parts of the "body" to determine which parts of the cabin are contacted during an accident.

We live in a computer world, and therefore security specialists actively use virtual simulation in their work. This allows you to collect much more data and, in addition, such dummies are almost eternal. Toyota programmers, for example, have developed more than a dozen models that mimic people of all ages and anthropometric data. And Volvo even created a digital pregnant woman.

Conclusion

Every year, about 1.2 million people die in road accidents around the world, and half a million are injured and disabled. In an effort to draw attention to these tragic figures, the UN in 2005 declared every third Sunday in November as World Day of Remembrance for Road Traffic Victims. Carrying out crash tests allows you to increase the safety of cars and thereby reduce the above sad statistics.

Send your good work in the knowledge base is simple. Use the form below

Students, graduate students, young scientists who use the knowledge base in their studies and work will be very grateful to you.

Posted on http://www.allbest.ru/

Course work

by discipline: Regulation and standardization of requirements for the safety of vehicles.

Topic: Active and passive vehicle safety

Introduction

3. Normative documents regulating road safety

Conclusion

Literature

Introduction

The reliability and serviceability of each vehicle on the road ensures road safety in general. The safety of the car directly depends on its design and is divided into active and passive.

car accident transport safety

1. Active car safety

Active safety of a car is a combination of its design and operational properties aimed at preventing and reducing the likelihood of an emergency on the road.

Basic properties:

1) Traction

2) Brake

3) Stability

4) Manageability

5) Patency

6) Informative

RELIABILITY

VEHICLE LAYOUT

The layout of cars is of three types:

Better stability and handling when driving at high speed, especially on wet and slippery roads;

Ensuring the necessary weight load on the drive wheels;

Less noise level, which is facilitated by the absence of a cardan shaft.

At the same time, front-wheel drive vehicles have a number of disadvantages:

At full load, acceleration on the rise and on wet roads deteriorates;

The tires of the front driving steered wheels are loaded more, respectively, more subject to wear;

Front wheel drive requires the use of complex units - constant velocity joints (CV joints)

The combination of the power unit (engine and gearbox) with the final drive complicates access to individual elements.

BRAKING PROPERTIES

Modern cars use an anti-lock braking system (ABS) that adjusts the braking force of each wheel and prevents them from slipping.

In winter and summer, the condition of the road surface is different, so for the best realization of the braking properties, it is necessary to use tires that correspond to the season.

TRACTION PROPERTIES

VEHICLE STABILITY

Stability - the ability of a car to keep moving along a given trajectory, opposing the forces that cause it to skid and roll over in various road conditions at high speeds.

There are the following types of stability:

Transverse with rectilinear movement (course stability).

Transverse during curvilinear motion.

Longitudinal.

Its violation is manifested in the slipping of the drive wheels when overcoming long icy or snowy slopes and the car sliding back. This is especially true for road trains.

DRIVABILITY OF THE VEHICLE

Handling - the ability of the car to move in the direction set by the driver.

Insufficient - the car increases the turning radius;

Neutral - the turning radius does not change;

Excessive - the turning radius is reduced.

Distinguish tire and roll understeer.

Tire steering

Roll Steering

INFORMATION

It depends on the following factors:

The location of the instrument panel, buttons and control keys, gear lever, etc. should provide the driver with a minimum amount of time to check indications, actions on switches, etc.

2. Passive car safety

Passive safety of a car is a set of design and operational properties of a car aimed at reducing the severity of an accident.

It is divided into external and internal.

The internal includes measures to protect people sitting in the car through special interior equipment.

Such as:

· Seat belts

Airbags

Headrests

Safety steering block

Life support zone

External passive safety includes measures to protect passengers by giving the body special properties, for example, the absence of sharp corners, deformation.

Such as:

body shape

Safety elements

Provides acceptable load on the human body from a sharp deceleration in an accident and saves space in the passenger compartment after deformation of the body.

SEAT BELTS

In order for the belt to work properly for its purpose, it must fit snugly against the body. Previously, belts had to be adjusted, adjusted to fit. With the advent of inertial belts, the need for “manual adjustment” has disappeared - in the normal state, the coil rotates freely, and the belt can wrap around a passenger of any build, it does not hinder actions, and every time the passenger wants to change the position of the body, the strap always fits snugly to the body. But at the moment when the "force majeure" comes - the inertial coil will immediately fix the belt. In addition, on modern machines, squibs are used in belts. Small explosive charges detonate, pulling the belt, and he presses the passenger to the back of the seat, preventing him from hitting.

Seat belts are one of the most effective means of protection in an accident.

Therefore, passenger cars must be equipped with seat belts if attachment points are provided for this. The protective properties of belts largely depend on their technical condition. Belt malfunctions, in which the vehicle is not allowed to be operated, include tears and abrasions of the fabric tape of the straps visible to the naked eye, unreliable fixation of the tongue of the strap in the lock or the absence of automatic ejection of the tongue when the lock is unlocked. For inertia-type seat belts, the webbing should be freely retracted into the coil and blocked when the car is moving sharply at a speed of 15 - 20 km / h. Belts that have experienced critical loads during an accident in which the car body has received serious damage are subject to replacement.

AIRBAGS

Today, airbags are commonplace not only in expensive cars, but also in small (and relatively inexpensive) cars. Why are airbags needed? And what are they?

Here is a diagram of how the airbag system works:

Studies of the effect of airbags on the likelihood of driver death in frontal collisions have shown that it is reduced by 20-25%.

If the airbags have deployed or been damaged in any way, they cannot be repaired. The entire airbag system must be replaced.

There are statistics on the impact of airbags on injuries in an accident. What can be done to reduce the chance of injury?

If your car has an airbag, do not place rear-facing child seats on a vehicle seat where the airbag is located. When inflated, the airbag may move the seat and cause injury to the child.

HEADRESTS

SAFETY STEERING GEAR

Safety steering is one of the constructive measures that ensure the passive safety of the car - the ability to reduce the severity of the consequences of traffic accidents. The steering gear can cause serious injury to the driver in a frontal collision with an obstacle when the front of the vehicle is crushed when the entire steering gear moves towards the driver.

EMERGENCY EXITS

3. The main regulatory documents governing road safety.

The main regulatory documents regulating road safety are:

1. Laws:

Federal Law of the Russian Federation "On traffic safety" dated 10.12.95. No. 196-FZ;

Code of the RSFSR on Administrative Offenses;

Criminal Code of the Russian Federation;

Civil Code of the Russian Federation;

Decree of the Government of the Russian Federation of September 10, 2009 N 720 (as amended on December 22, 2012, as amended on April 8, 2014) "On approval of the technical regulation on the safety of wheeled vehicles";

Decree of the President of the Russian Federation No. 711 dated 15.06.98. "On additional measures to ensure traffic safety".

2. GOSTs and norms:

GOST 25478-91. Vehicles. Requirements for the technical condition according to the conditions of the database.

GOST R 50597-93. Highways and streets. Requirements for the operational state, admissible under the terms of traffic safety.

GOST 21399-75. Diesel vehicles. Exhaust smoke.

GOST 27435-87. The level of external car noise.

GOST 17.2.2.03-87. Nature protection. Norms and methods for measuring the content of carbon monoxide and hydrocarbons in the exhaust gases of vehicles with gasoline engines.

3. Rules and Regulations:

Rules for the transportation of dangerous goods by road RF8.08.95. No. 73;

Basic provisions on vehicles for operation and duties of officials to ensure traffic safety. Decree of the Council of Ministers-Government of the Russian Federation 23.10.93. No. 1090;

Regulations on ensuring traffic safety in enterprises, institutions, organizations engaged in the transportation of passengers and goods. Ministry of Transport of the Russian Federation 09.03.95 No. 27.

Instructions for the transportation of bulky and heavy goods by road on the roads of the Russian Federation. Ministry of Transport of the Russian Federation 27.05.97

Order of the Ministry of Health of the Russian Federation "On the procedure for conducting preliminary and periodic medical examinations of workers and medical regulations for admission to the profession" No. 90 dated 14.03.96.

Regulations on the procedure for attestation of the positions of executive managers and specialists of transport enterprises. Ministry of Transport of the Russian Federation and Ministry of Labor of the Russian Federation 11.03.94 No. 13./111520.

Regulations on ensuring the safety of passenger transportation by buses. Min.trans. RF 08.01.97 No. 2.

Regulations on working hours and rest periods for drivers. State Committee for Labor and Issues and the All-Union Central Council of Trade Unions 16.08.77. No. 255/16.

Order of the Ministry of Health of the Russian Federation "On the approval of a first aid kit (automobile)" No. 325 dated 14.08.96.

Regulations on the Russian Transport Inspectorate. Ministry of Transport of the Russian Federation Government of the Russian Federation 26.11.97 No. 20.

4. Active and passive safety of vehicles of category M1

2. Active safety requirements

2.1. Requirements for brake systems

2.1.1. The vehicle is equipped with braking systems capable of performing the following braking functions:

2.1.1.1. Working brake system:

2.1.1.1.1. Acts on all wheels from one control

2.1.1.1.2. When the driver acts on the control from his seat, when both hands of the driver are on the steering control, it slows down the movement of the vehicle up to a complete stop both when moving forward and in reverse.

2.1.1.2. The spare brake system is capable of:

2.1.1.2.1. For vehicles with four or more wheels, act on the brakes through at least half of the dual-circuit service brake system on at least two wheels (on each side of the vehicle) in the event of a failure in the service brake system or brake booster systems;

2.1.1.3. Parking brake system:

2.1.1.3.1. Brakes all wheels on at least one of the axles;

2.1.1.3.2. It has a control that, when actuated, is capable of maintaining the vehicle's inhibited state only mechanically.

2.1.2. Braking forces on the wheels should not be generated if the brake controls are not engaged.

2.1.3. The operation of the working and spare brake systems ensures a smooth, adequate decrease or increase in braking forces (vehicle deceleration) with a decrease or increase, respectively, of the force exerted on the brake system control.

2.1.4. For vehicles with four wheels or more, the hydraulic brake system is equipped with a red warning light, which is activated by a signal from a pressure sensor, informing about the failure of any part of the hydraulic brake system associated with brake fluid leakage.

2.1.5. Bodies of management and control.

2.1.5.1. Working brake system:

2.1.5.1.1. A foot control (pedal) is used, which moves without interference, when the foot is in a natural position. This requirement does not apply to vehicles designed to be driven by persons whose physical capabilities do not allow driving the vehicle with their feet, and vehicles of categories L.

2.1.5.1.1.1. When the pedal is pressed all the way down, there should be a gap between the pedal and the floor.

2.1.5.1.1.2. When released, the pedal should fully return to its original position.

2.1.5.1.2. The working brake system provides for compensatory adjustment in connection with the wear of the friction material of the brake linings. Such adjustment should be carried out automatically on all axles of vehicles with four wheels or more.

2.1.5.1.3. If there are separate controls for the service and emergency brake systems, the simultaneous actuation of both controls shall not lead to the simultaneous disabling of the service and emergency braking systems.

2.1.5.2. Parking brake system

2.1.5.2.1. The parking brake system is equipped with a control independent of the service brake control. The parking brake control is equipped with a functional locking mechanism.

2.1.5.2.2. The parking brake system provides for manual or automatic compensation adjustment due to wear of the friction material of the brake linings.

2.1.7. In order to ensure periodic technical checks of the brake systems, it is possible to check the wear of the service brake linings of the vehicle using only the tools or devices normally supplied with it, for example, using appropriate inspection holes or in some other way. As an alternative, audible or optical devices are allowed to warn the driver at his workplace of the need to replace the pads. A yellow warning signal can be used as a visual warning signal.

2.2. Tire and wheel requirements

2.2.1. Each tire fitted to the vehicle:

2.2.1.1. It has a molded marking with at least one of the conformity marks "E", "e" or "DOT".

2.2.1.2. It has molded markings for tire size, load capacity index and speed category index.

2.3. Visibility Requirements

2.3.1. The driver who will drive the vehicle must be able to see the road ahead of him unobstructed, as well as have a view to the right and left of the vehicle.

2.3.2. The vehicle is equipped with a permanently built-in system capable of clearing the windshield from icing and fogging. A system that uses heated air to clean glass must have a fan and air supply to the windshield through nozzles.

2.3.3. The vehicle is equipped with at least one windshield wiper and at least one windshield washer jet.

2.3.4. Each of the wiper blades after turning off automatically returns to its original position, located on the border of the cleaning zone or below it.

2.4. requirements for speedometers

2.4.2 The speedometer readings are visible at any time of the day.

2.4.3. The speed of the vehicle according to the speedometer must not be less than its actual speed.

3. Requirements for passive safety

3.1. Safety requirements for steering of vehicles of categories (with automotive layout)

3.1.1. The steering wheel must not snag or catch on any part of the driver's clothing or jewelry under normal use.

3.1.2. The bolts used to attach the steering wheel to the hub, if they are on the outside, are recessed flush with the surface.

3.1.3. Uncoated metal spokes can be used if they have specified corner radii.

3.2. Requirements for seat belts and their attachment points

3.2.1. The seats of vehicles of categories M1 (with automotive layout), with the exception of seats intended for use exclusively in a stationary vehicle, are equipped with seat belts.

In the case of seats that can be rotated or installed in other directions, it is necessary to equip the seat belts only installed in the direction intended for use when the vehicle is moving.

3.2.2. The minimum requirements for seat belt types for different seat types and vehicle categories are shown in Table 3.1.

3.2.3. Retractors must not be used with seat belts:

Table 3.1 Minimum requirements for seat belt types

3.2.3.1. Which do not have a regulator for the length of the stretched strap;

3.2.3.2. Which require manual actuation of a device to obtain the desired length of the webbing and which automatically lock when the user has reached the desired length.

3.2.4. Three-point belts with retractors have at least one diagonal webbing retractor.

3.2.5. Except as noted in paragraph 3.2.6., each passenger seat equipped with an airbag shall be provided with a warning sign against the use of a rearward facing child restraint. The pictogram warning label, which may include explanatory text, is securely attached and positioned so that it can be seen by the person who intends to install a rearward facing child restraint in the seat. The warning sign must be visible in all cases, including when the door is closed.

Pictogram - red;

Seat, child seat and airbag contour line - black;

The words "Air Bag" ("airbag"), as well as airbags - white.

3.2.6. The requirements of paragraph 3.2.5. do not apply if the vehicle is equipped with a sensor mechanism that automatically detects the presence of a rearward facing child restraint and prevents the airbag from deploying when such a child restraint system is fitted.

3.2.7. Seat belts are installed in such a way that:

3.2.7.1. There was practically no possibility of slipping off the shoulder of a correctly worn belt as a result of the driver or passenger moving forward;

3.2.7.2. There was practically no possibility of damage to the belt strap when in contact with sharp, hard structural elements of the vehicle or the seat of child restraint systems and ISOFIX child restraint systems.

3.2.8. The design and installation of seat belts allow you to fasten them at any time. If the seat assembly or seat cushion and/or seat back can be folded down to provide access to the rear of the vehicle or to the cargo or luggage compartment, then when they are folded back and then returned to their normal position, the seat belts provided must be accessible or easily removed from the - under the seat, or because of it, by the user without assistance.

3.2.9. The device for opening the buckle is highly visible and easily accessible to the user and is designed in such a way that it cannot be opened unexpectedly or accidentally.

3.2.10. The buckle is located in such a place that it is easily accessible for the rescuer in the event that it is necessary to urgently release the driver or passenger from the vehicle.

3.2.11. The buckle is installed in such a way that, both in the open state and under the load of the user's weight, he can open it with a simple movement of both the left and right hand in one direction.

3.2.12. When worn, the belt is either adjusted automatically or is designed so that the manual adjustment device is easily accessible to the seated user and is comfortable and easy to use. In addition, the user must be able to tighten the belt with one hand, adjusting it to their body size and the position in which the vehicle seat is located.

3.2.13. Each seating position is equipped with seat belt attachment points appropriate for the type of belt used.

3.2.14. If a double-leaf door structure is used to provide access to the front and rear seats, then the design of the belt anchorage system must not prevent free entry and exit from the vehicle.

3.2.15. Fastening points are not located on thin and/or flat panels with insufficient rigidity and reinforcement or in thin-walled pipes.

3.2.16. When visually inspecting the places of attachment of seat belts, there are no gaps in the weld, visible lack of penetration.

3.2.17. The bolts used in the construction of the seat belt attachment points must be grade 8.8 or better. Such bolts are marked with the designation 8.8 or 12.9 on the hex head, but bolts 7/16? UNF seat belt anchors (anodized) not marked with the indicated designations may be considered equivalent strength bolts. The thread diameter of the bolts is not less than M8.

3.3. Requirements for seats and their fastenings

3.3.1. The seats are securely attached to the chassis or other parts of the vehicle.

3.3.2. On vehicles equipped with mechanisms for longitudinal adjustment of the position of the cushion and the angle of inclination of the seatbacks or a mechanism for moving the seat (for boarding and disembarking passengers), these mechanisms must be operable. After the termination of regulation or use, these mechanisms are automatically blocked.

3.3.3. Head restraints are fitted to each front outboard seat of M1 category vehicles.

3.4. Requirements for the safety of the internal equipment of vehicles of category M1.

3.4.1. The surfaces of the internal volume of the passenger compartment of the vehicle must not have sharp edges.

Note: A sharp edge is considered to be an edge of hard material that has a radius of curvature less than 2.5 mm, except for protrusions on the surface with a height of not more than 3.2 mm. In this case, the requirement of a minimum radius of curvature does not apply, provided that the height of the protrusion is not more than half its width and its edges are blunted.

3.4.2. The front surfaces of the seat frame, behind which is located the seat intended for normal use while the vehicle is in motion, are covered at the top and rear with non-rigid upholstery material.

Note: A non-rigid upholstery material is a material that has the ability to bulge with the pressure of a finger and returns to its original state after removal of the load, and when compressed, retains the ability to protect against direct contact with the surface it covers.

3.4.3. Shelves for things or similar elements of the interior do not have brackets or fasteners with protruding edges and, if they have parts protruding into the interior of the vehicle, then such parts have a height of at least 25 mm, with edges rounded with radii of at least 3.2 mm, and covered with non-rigid upholstery material.

3.4.4. The inner surface of the body and the elements mounted on it (for example, handrails, lamps, sun visors) located in front of and above the seated driver and passengers, which can contact a sphere with a diameter of 165 mm, if they have protruding parts made of rigid material, satisfy the following requirements:

3.4.4.1. The width of the protruding parts is not less than the size of the protrusion;

3.4.4.2. If these are roof elements, the radius of rounding of the edges is not less than 5 mm;

3.4.4.3. In the case of roof-mounted components, the radii of the contact edges must not be less than 3.2 mm;

3.4.4.4. Any roof slats and ribs, other than the front frames of glazed surfaces and door frames, made of rigid material shall not protrude more than 19 mm downwards.

3.4.5. The requirements of paragraph 3.4.4 apply, inter alia, to vehicles with an opening roof, including opening and closing devices in the "closed" position, but do not apply to vehicles with folding soft tops in terms of parts of the folding top covered with non-rigid upholstery. material, and folding roof frame elements.

3.5. Requirements for doors, locks and door hinges of vehicles of category M1

3.5.1. All doors that open access to the vehicle can be securely locked with locks when closed.

3.5.2. The door lock mechanisms for the entry and exit of the driver and passengers have two locking positions: intermediate and final.

3.5.3. Hinged door lock mechanisms do not open in either the intermediate or final locking positions when a force of 300 N is applied.

3.6. Requirements for safety of external ledges of vehicles of categories M1

3.6.1. In the area of the outer surface of the body, located between the floor line and a height of 2 m from the road surface, there are no structural elements that could catch (hook) or increase the risk or severity of injury to any person who may come into contact with the vehicle.

3.6.2. Emblems and other decorative objects protruding more than 10 mm, including any substrate, above the surface to which they are attached, are capable of deflecting or breaking off when a force of 100 N is applied to them, and, when deflected or broken off, do not protrude above the surface, to which they are attached, more than 10 mm.

3.6.3. Wheels, wheel nuts or bolts, hub caps and wheel covers do not have sharp or cutting edges protruding beyond the surface of the wheel rim.

3.6.4. The wheels do not have wing nuts.

3.6.5. The wheels do not protrude beyond the outer contour of the body in plan, with the exception of tires, wheel caps and wheel nuts.

3.6.6. Side air deflectors or gutters, unless they are bent towards the body so that their edges cannot touch a 100 mm diameter ball, have a chamfer radius of at least 1 mm.

3.6.7. The ends of the bumpers are bent towards the body so that a ball with a diameter of 100 mm cannot come into contact with them, and the distance between the edge of the bumper and the body does not exceed 20 mm. Alternatively, the ends of the bumper may be recessed into recesses in the body or have a common surface with the body.

3.6.8. Drawbars and winches (if equipped) do not protrude beyond the front surface of the bumper. It is allowed for the winch to protrude beyond the front surface of the bumper if it is covered by a suitable protective element having a radius of curvature of less than 2.5 mm.

3.6.9. For vehicles of category M1, the door and trunk handles do not protrude beyond the outer surface of the body by more than 40 mm, the remaining protruding elements - by more than 30 mm.

3.6.11. The open ends of rotary handles rotating parallel to the plane of the door must be bent towards the surface of the body.

3.6.12. Rotary handles that rotate outwards in any direction, but not parallel to the plane of the door, in the closed position are protected by a safety frame or recessed. The end of the handle is directed either back or down.

3.6.13. Window glasses that open outward in relation to the outer surface of the vehicle do not have edges directed forward when opened, and also do not protrude beyond the edge of the overall width of the vehicle.

3.6.14. Headlight rims and visors do not protrude more than 30 mm in relation to the most protruding point of the headlight glass surface (when measured horizontally from the point of contact of a sphere with a diameter of 100 mm simultaneously with the headlight glass and with the rim (visor) of the headlight).

3.6.15. Jacking brackets do not protrude more than 10 mm from the vertical projection of the floor line directly above them.

3.6.16. Exhaust pipes protruding beyond the vertical projection of the floor line located directly above them by more than 10 mm end with a nozzle or a rounded edge with a radius of curvature of at least 2.5 mm.

3.6.17. The edges of the steps and steps should be rounded. 3.6.18. The radius of curvature of the outwardly protruding edges of the side air fairings, rain shields and anti-dirt window deflectors is not less than 1 mm.

3.7. Requirements for rear and side guards

3.7.2. The width of the rear guard must not exceed the width of the rear axle and not be shorter than it by more than 100 mm on each side.

3.7.3. The height of the rear guard must be at least 100mm.

3.7.4. The ends of the rear guard must not be bent back.

3.7.5. The rear surface of the rear protective device must be separated from the rear clearance of the vehicle by no more than 400 mm.

3.7.6. The edges of the rear protective device shall be rounded with a radius of at least 2.5 mm.

3.7.7. The distance from the supporting surface to the lower edge of the rear protective device throughout its entire length does not exceed 550 mm.

3.7.8. The side protector must not protrude beyond the width of the vehicle.

3.7.9. The outer surface of the side protective device shall be no more than 120 mm inward from the side clearance of the vehicle. In the rear part, for at least 250 mm, the outer surface of the side protector must be no more than 30 mm inward from the outer edge of the outer rear tire (excluding deflection of the tire in the lower part under the weight of the vehicle). Bolts, rivets and other fasteners may protrude up to 10 mm from the outer surface. All edges are rounded with a radius of at least 2.5 mm.

3.7.10. If the side protection device consists of horizontal profiles, the distance between them must not exceed 300 mm and their height must not be less than:

3.7.11. The front end of the side protector is horizontally spaced:

3.7.11.1. For trucks, no more than 300 mm from the rear surface of the front tire tread. If there is a cabin in the indicated zone, then - no more than 100 mm from the rear surface of the cabin;

3.7.11.2. For trailers not more than 500 mm from the rear surface of the front wheel tread;

3.7.11.3. For semi-trailers, not more than 250 mm from the supports and not more than 2.7 m from the center of the kingpin.

3.7.12. The rear end of the side protector is horizontally spaced no more than 300 mm from the front surface of the rear wheel tread.

3.7.13. The distance from the supporting surface to the lower edge of the side protective device throughout its entire length does not exceed 550 mm.

3.7.14. The spare wheel, battery container, fuel tanks, brake reservoirs and other components permanently attached to the vehicle body may be considered as part of the side protector if they meet the above dimensional requirements.

3.8. fire safety requirements

3.8.1. Fuel that may spill when filling the fuel tank(s) does not enter the exhaust system, but is discharged to the ground.

3.8.2. The fuel tank (tanks) is not located in the passenger room or other compartment, which is its integral part, and does not constitute any of its surface (floor, wall, partition). The passenger compartment is separated from the fuel tank(s) by a partition. The baffle may have openings, provided that they are designed in such a way that, under normal operating conditions, fuel from the tank(s) cannot flow freely into the passenger space or other compartment forming part of it.

3.8.3. The filler neck of the fuel tank is not located in the passenger compartment, in the luggage compartment and in the engine compartment and is provided with a cap to prevent fuel spillage.

3.8.4. The filler cap is attached to the filler pipe.

3.8.5. The requirements of paragraph 3.8.4. are also considered fulfilled if measures are taken to prevent leakage of excess vapors and fuel in the absence of a filler cap. This can be achieved through one of the following measures:

3.8.5.1. The use of a non-removable fuel filler cap that opens and closes automatically;

3.8.5.2. The use of structural elements that prevent leakage of excess vapors and fuel in the absence of a filler cap;

3.8.5.3. Taking any other measure that has a similar result. Examples may include, in particular, the use of a lid with a cable, a lid provided with a chain, or a lid that uses the same key to open as the vehicle's ignition switch. In the latter case, the key must only be removed from the filler cap lock in the locked position.

3.8.6. The seal between the cover and the filling pipe is firmly fixed. In the closed position, the lid fits snugly against the seal and the filling pipe.

3.8.7. There are no protrusions, sharp edges, etc. near the fuel tank(s) so that the fuel tank(s) are protected in the event of a frontal or side collision of the vehicle.

3.8.8. The fuel system components are protected by parts of the chassis or body from contact with possible obstacles on the ground. Such protection is not required if the components located in the lower part of the vehicle are located in relation to the ground above the part of the chassis or bodywork located in front of them.

5. Ways to improve external passive safety

External passive safety reduces injuries to other road users: pedestrians, drivers and passengers of other vehicles involved in an accident, and also reduces mechanical damage to the cars themselves. This safety is possible when there are no protruding handles or sharp corners on the outer surface of the car.

Literature

1. Theory and design of the car and engine

2. Vakhlamov V.K., Shatrov M.G., Yurchevsky A.A. Agafonov A.P., Plekhanov I.P. Car: Study Guide. ? M.: Education, 2005.

3. Decree of the Government of the Russian Federation of September 10, 2009 N 720 (as amended on December 22, 2012, as amended on April 8, 2014) "On approval of the technical regulation on the safety of wheeled vehicles"

4. Volgin V.V. Driving textbook. ? M.: Astrel? AST, 2003.

5. Nazarov G. Self-instruction manual for driving a car. - Rostov n / a.: Phoenix, 2006.

Hosted on Allbest.ru

...