New Aircraft Wheel Brake Control Technology

Aircraft antiskid braking system is one of the key airborne equipment and plays a very important role in safe takeoff and landing. Antiskid braking system must prove tires don't slip extremely on the track, and prove aircraft land safely and stably with maximum braking effectiveness. It is very meaningful to research the digital antiskid braking control box and apply with advance control theory. The control box designed with DSP TMS320LF2407 and fuzzy control strategy optimized by genetic algorithm are presented in the article.The first, some control methods of the anti-skid braking system are analyzed and compared. Then, according to the specialty of the anti-skid braking system, the fuzzy control strategy is presented. The fuzzy model of the anti-skid braking system is set up. On the basic of it, the design of fuzzy controller and rule of control has been finished. The inputs of fuzzy controller are the error of slip ratio and its change ratio, the output of fuzzy controller is the control current of the servo valve.Because fuzzy control is based on the experience of human being, the precision control rules are difficult to be obtained. So a kind of genetic algorithm is adopted to optimize fuzzy control rules. The fuzzy control rules are coded by binary system, and crossover and mutation operating is self-adapted according to the feedback in the genetic algorithm.Antiskid braking control box is designed with high-performance digital signal processor TMS320LF2407, and the measuring circuits of wheel speed sensor, instruct sensor are redesigned in the article. The driver of electro-hydraulic servo system is also redesigned by PWM control way. At last, assistant functions of antiskid braking system is analyzing.The control of the anti-skid braking system has already passed the experiment on the road. The result shows that the hardware design of the control box is feasible, the control strategy used is correct and efficiency. The system is stable and the performance of the anti-skid braking system is improved.