汽车安全系统分析外文文献

Automotive safety systems and technology research and analysis

As traffic tools of the modernization and absolute number increase sharply, traffic accidents are also increasing. Car accident has become severe global social issues. Undoubtedly, advanced auto safety facilities are the driving safety indispensable safeguard. So, we should start, from technology to research and development of high performance, high safety car, also want to strengthen the regular inspection in cars, so timely maintenance investigation, make cars often in good technical status, so as to improve the safety performance of the car.

Here we introduced active safety technology and automobile car passive safety technology. Auto safety is according to the traffic accident happened before and after the classified. One is in a traffic accident take safety measures, especially before immediately will produce risk condition, drivers manipulate the steering wheel avoid or emergency brake to avoid traffic accidents. In the car, drive in usually to ensure the basic manipulation stability, drivers on the surrounding environment and to ensure the visual recognition sex drive the car itself, developed the basic performance ant-lock braking system (ABS), prevent slippery drive system (ASR), active suspension, power steering and four-wheel drive (4WD), four-wheel steering (4WS), lighting system, wiper, the rearview mirror, prevent from rear-end collision car alarm system and laser radar, etc. These security devices and technology, called active safety system, can also be called preventive security system. On the other hand, in order to reduce traffic accidents and company by personnel directly suffer degree, ensure company take staff and pedestrian safety, says the security for passive safety, can also be called conflict safety. When after the accident, in order to prevent disasters, including prevent the expansion of fire and make crew from traffic accident can extricate the security devices and systems, called prevent disaster expand security system. One．Automobile active security technology

1. ABS braking system

Ant-lock Braking System (Braking System, lock do by ABS computers as ABS), hydraulic device, the wheel speed sensors, brake hydraulic pipeline and electrical wiring etc. Their structures are shown below.

ABS tasseled for the car in various driving conditions braking performance and brake safety particularly important, especially is emergency braking, can make full use of the peak between tire and road surface adhesion properties, improve performance and reduce automobile fight sideslip braking distance, give full play to the braking performance, but also increase the automobile braking process control. So as to reduce the possibility of car accidents.

No installation ABS car, if the driving force trample brake pedal, wheel will rapidly lower speed, and finally wheels stop turning, but body because of inertia remains forward sliding. This phenomenon was at the wheel and pavement occur between larger "slip", appear this kind of situation, the car tires of automobile lateral spreads almost disappear, so poor force will appear the following phenomena:

(1) Steering stability fall: the steering wheel is ineffective, vehicle tail manipulation of curl, serious when vehicle circles or appear folding phenomenon;

(2) Handling fall: manipulate the steering wheel and short of steering requirements;

(3) Braking distance extended: more than general braking distance.

So, we can imagine to have installed ABS system of the car safety is very important.

2．the ASR drive torque control system

ABS are used to prevent car braking process wheel lock, will wheel sliding rate control in ideal range, so as to shorten the braking distance, improve automobile braking direction stability and steering control, so as to improve the safety of the car. Along with the increase of vehicle performance requirements, not only in braking process required to prevent wheel lock, and asked the driver to prevent drive roller skating turn in the process, making cars in the direction stability, driving process steering control ability and acceleration performance, so are improved by the car drive torque steering system ASR (Accelerations

Regulation) Slip. ASR is the perfect complement and ABS ASR, but most alone is set with ABS combined together, commonly used ABS/ASR says, called antiskid control system.

ASR is mainly used to prevent car in the beginning, accelerate the wheels, guarantee slip in the car accelerated rate and improve the stability in bad pavement drive attached conditions. It makes no difference speed in the car lock ice roads and muddy road started and to improve its capacity, also can prevent high in speed by turning cars gliding pavement and rear lateral spreads phenomenon.

Anyhow, prevent the wheel because ASR slip, can maximize the engine driving moment of cars had enough, ensure the longitudinal force, lateral force and manipulation of power, make cars in starting, steering and accelerate the process, in gliding and muddy road, in a mountain area downhill process can steadily driving, guarantees the safety, reducing tire wear and fuel consumption, and improves the car driving capability.

3．VDC system

ABS/ASR system successfully solves the brake and the car when driven direction stability problem, but cannot solve the vehicle steering stability problem driving direction. For example when steering road, inevitably by lateral and longitudinal force, only local surface can provide full lateral and longitudinal force, the pilot can control vehicles. If the ground adhesion ability lower lateral, will damage cars driving ability predetermined direction. Rainy days cars driving, often high-speed steering lateral sliding out, it is the ground because of insufficient lateral adhesion ability. To resolve the issue, and developed countries automobile industry recently in ABS/ASR system on the basis of the development of dynamic Control system (into car Dynamics Control, the abbreviation VDC Vehicle). The system of the car brake, driving, suspension, steering, engine and so on various main assembly control system in function, structure organic ground comprehensive together, can make cars in all kinds of bad working conditions, such as ice road pavement, commuting, river bend pavement and took evasive action moving line, braking and acceleration and the downhill for different conditions, such as bearing, different type pressure and different levels of type wear all

have good direction stability, to show the best driving performance. VDC applications, in braking, acceleration and steering aspects of driver's fully released request, is the car of active safety driving a new milestone.

VDC of steering control system is mainly by driving for each wheel brake control and engine power output control to realize. For example, if the car turn left front wheel for steering the inadequate capacity tend to slip out of the corner, VDC system can measure imminent, just know lateral spreads left rear brake adopt appropriate measures. If at the same corner, because rear wheel tend to slip out of favor of lateral overmuch, VDC system is proper braking to front-right wheel failure, maintain the stability of the vehicle driving. In extreme cases, VDC system can also take reduce engine to reduce the power output, and to reduce the speed of the demand side adhesion ability to maintain the stability of the vehicle driving. Adopt VDC system, automobile in folio pavement or corner of pavement braking distance still can further reduce.

4． CCS cars cruise control system

Auto cruise Control System (Cruiser Control System, abbreviation for CCS) is can make automobile work in engine favorable speed range, reduce driver's driving manipulate labor intensity, improve the driving comfort the automatic driving device.

Car cruising system (CCS) role is required by the driver: after a normally-closed switch, no speed on the accelerator pedal can automatically keep the speed, make the vehicle with the fixed speed. Using this device, when on the highway after a long time, the driver driving not have to control the accelerator pedal, reduce fatigue, while reducing unnecessary speed change, can reduce save fuel.

Auto cruise control system is the earliest development of the automotive electronic control system. This system USES another speed sensor, will speed signal input engine control microcomputer, by microcomputer control vacuum system work. This system can make use of the server, speed control switch lever and brake pedal on vacuum lift switches etc, its function and basic system the same.

In this system, electronic control device can accord change of driving

resistance, automatic regulation engine throttle Angle, make the speed constant. Such not only reduce unnecessary speed change, which saves fuel, also reduced the driver's burden. The electronic cruise control system which is shown in figure 2.

Two. Automobile passive safety technology

1. Seat belt

Car seat belt is a safety device, it can in car collision or sharp turn, make crew to keep its original position as possible without mobile and rotation, avoid collision with in-car hard parts caused damage. Seat belts and airbags, as modern cars are safety devices, but the long history of the former, popularize the scope.

The seemingly simple seat belt actually not "simple". Attention has been at the forefront of traffic safety, through the analysis of general motors after a car accident found: seat belt not only makes people protect the lives, can be in more than half of the accident to reduce or even eliminate drivers, motorists are the chance of injury. Car collision or unexpected emergency braking force generated great inertia, will allow the driver and passenger and car windscreen, steering wheel, seat, collision happened objects such as secondary to drive is caused extremely easily crew serious damage, even drive occupant seats or threw the apex, seat belts can will ride in the seat. Bondage personnel When has the accident, which can effectively prevent the collision, and its buffer role can absorbs a great deal of kinetic energy, reduce rides personnel extent of the injuries.

Fasten your seat belt airbags play our role is also an important condition. Because the airbag to maximize role for the ride in the impact of the physical location, sitting instant action have extremely strict and the requirements. Otherwise, the airbag started strong instantaneous wallops to head are fragile site, may cause serious damage, especially for children, this damage can be fatal. Even the most ordinary three belts, try a can timely in crash that lived rides the bundle, ensure the upper part of a ride in the airbag fully extended range, make the airbag most effectively play efficacy. Accordingly, must not because the car is equipped with airbags and feel carefree seat belt fastened, only to reduce

or eliminate the traffic accident happen.

2. The airbag

When the front collision happened strong, because inertia, who rides the body forward fast moving, then seat belts and will try to "pull" rides on person the body, absorb some of the impact energy, while the airbag with "the eyepiece trend" inflatable and completely open; Then the rides the upper body will sink to airbags, gas also began from the vent air uniform escaping, and absorbed most of the impact energy; Subsequently, the ride back seat and return to the body. Above the whole process is almost always happens in a flash, who rides the completely in passive situation, in this case, the passive rely on auxiliary occupant protection system is the only option. Airbags development design is based on the protection on seat belt Co., LTD; they cooperate with each other to ride the play the auxiliary protective effect.

Seat belt usage in under the condition of the crew, balloon help reduce chest, head and facial injuries in the seriousness of the collision. When car collision happened before, the first is the car to stop motion, car under the action of inertial force crews to go forward with the original speed still sport. Not wearing a seatbelt crews will and steering dish, front windscreen together, so it can be severely hurt; Wearing a seatbelt as car stop the crew can stop moving forward movement and gradually. If collision violent, crew forward movement of the seat belts, even faster in the complete stop before motion, still and in-car things together. If this fashion in steering the disk or within the popup balloon inflated dash, it can protect the occupant reduce the possibility of car together with things, more uniform dispersion head, chest, absorb the impact energy of movement, thus crew has added effect of seat belts.

In addition to seat belts and airbags outside car passive safety technology includes car bumper, automobile safety glass, security body, occupant head and neck protection system (WHIPS), etc. These vehicles to improve the safety performance has very important contribution

Three. Automobile active safety new technology