Research Of Emergency Braking System Of Preventing Mistakenly Stepping On The Accelerator

As for frequent occurrence of traffic accidents in which drivers take mistakenly accelerator pedal as brake pedal.The paper sets logic rules for judging whether the drivers step mistakenly on the accelerator, with force and a ccelerated speed towards the accelerator pedal, the distance between the vehicle and the obstacles before as well as the steering wheel hand grip strength being parameters. Then with the aid of STC89C52 singlechip computers, the paper designs an emergency brake system based on judging parameters, also conducts relevant performance testing. Main tasks are as follows:1. Through looking up relevant reference and investigation, in combination with the current situation of techniques for preventing stepping on accelerator pedals unconsciously, the paper fully analyzed and studied the key elements as for such techniques, determining the judging elements and emergency braking program of this system.2. The paper made out overall designing program for the emergency brake system, selecting hardware which satisfied the designing demand, to design peripheral circuits like controlling module and emergency execution module.Also, according to the designing program, the paper finished commissioning and producing the above hardware.3. The paper determined critical values of each judging parameter, by analyzing and dealing with the signal for the force and accelerated speed of accelerator pedals, and signal for actual steering wheel hand grip strength during driving these si gnals were collected on three situations related to unconscious mistakenly stepping-on accelerator pedals, including steady acceleration, emergency acceleration and emergency situation; these values provide statistic support for the next judging logic during system software design. People who were involved in the test were aged from 20 to 50 years old.4. The paper set logic rules for judging, with force and accelerated speed towards the accelerator pedal, the distance between the vehicle and the obstacles before as well as the steering wheel hand grip strength being parameters and according to determined critical value of each judging parameter, therefore it put forwarded the overall software process of the system. Also i t made the Keil μVision integration opening environment as the opening platform of the overall software of the system, under which it compiled C-language programming for main program of the system, AD module, accelerated speed testing module, ultrasonic wa ve distance module, 12864 display module, stepper motor controlling module and alarm module. It described the designing,opening progress and main function of each programming module, and downloaded the overall software programming of system that had been designed to the hardware in order to operate the programming by STC-ISP downloading software.5. By using proteus software, the paper conducted simulation accordingly for the system to testify the feasibility of the programming and made tests of real vehicle. These tests showed that this system could judge the mistakenly stepping-on accelerator pedals accurately and conducted emergency braking. These tests also verified the actual feasibility of the emergency brake system.6. In the end, this paper concluded, and pointed out its innovation point and disadvantages, as well as made outlook for the future study.