The Control System Of An Crash Energy Absorption Equipment Combines Active And Passive Safety

Vehicle safety can be divided into two parts, active safety and passive safety. Active safety's goal is preventing car from accident, and passive safety's aim is decreasing the passenger injury severity. With the development of vehicle safety research, a new technology called active passive integration approach (APIA) which combines active and passive safety has been presented by internal and external researchers. APIA has been the trend of vehicle safety. Nowadays, some practical researches had been conducted on APIA, but there are only a few reports about it. Computer simulation results show that the vehicle safety can be improved by this technology effectively. The key technologies of APIA mostly has three parts, firstly, how to use the sensor technology and a sort of reasonable algorithm to constantly monitor the parameters of "human-vehicle-road" environment accurately; secondly, estimate the index of danger and predict the accident effectively; last but not the least, make the passive safety equipment work correctly and timely. Nowadays some active safety equipments, such as adaptive cruise control (ACC), anti-nap system and so on, has been equipped in some high-grade vehicles. Most of them use the radar ranging or video technology. Though these products worked successfully, they were costly and complex and they couldn't work well in some unexpected conditions, such as pedestrians cross the street abruptly, vehicles change the lane accidently and so on.Statistical analysis indicates that most of the driver could realize the danger before the crash, and emergency brake was conducted. Vehicle accelerations in emergency brake, ordinary brake, dot brake, and jumping over roadblocks were collected in real vehicle tests at 40kph,50kph and 60kph respectively. It had been found that, there exist obvious differences among emergency brake acceleration and other conditions. If the acceleration value is integrated by a moving window quadrature algorithm, as long as suitable width of moving window and appropriate critical value are defined, the emergency brake can be distinguished from ordinary brake, dot brake, or jumping over roadblocks. So, working with moving window quadrature algorithm, emergency brake action of driver can be used to predict the accident.So, based on the emergency brake action of driver, the control system of the crash energy absorption equipment which combines active and passive safety was developed. And the circuit and C-Program of this system was presented. Real vehicle tests show that the emergency brake action can be identified by this system, accident can be predicted effectively, and the energy absorption equipment can be controlled under the correct signal sent by this stable system.