Research Of Brake-by-wire Pedal Device

With the rapid development of automobile brake technology, vehicle safety andcomfort have become increasingly demanding, which requires braking system structuremore simple and reliable, more responsive, and easy to manage. Therefore, electricmechanical brake (EMB, Electric Mechanical Brake)system came into being, andbrake-by-wire pedal as an important part of the brake-by-wire system, of greatsignificance for increased safety and comfort, will become one of hot spots of researchat home and abroad.Designed a brake-by-wire pedal device for a particular model car. In order tovalidate the characteristics of the pedal, we established a three-dimensional model of thebrake-by-wire pedal by UG, then input it into ADAMS virtual prototype to do dynamiccharacteristics simulation. Then, conducted braking intention recognition by the methodof fuzzy identification, and executed braking intention recognition simulation in Matlab/Simulink in order to verify the validity of the method. Finally, processed physicalprototype of the brake-by-wire pedal, built hardware in the loop test platform, tovalidate the motion characteristics and to identify the real brake intentions of the pedal.Details are as follows:According to the braking requirements and functional analysis to determine thedesign scheme of the brake-by-wire pedal device; according to many different kinds ofcharacteristics curves of different cars determined the target curve as the basis of thesimulator’s design; then determined the simulator’s parameters and the form of thestructure of all components; design for all parts and check its structural strength andstiffness.Imported the three-dimensional model of the brake-by-wire brake pedal intoADAMS/View, based on the actual working conditions of the brake-by-wire pedal,added constraints and loads, then, carried on dynamic simulation. Compared thesimulation characteristic curve to the initial characteristic curve, which generallycoincide, verified the rationality of brake-by-wire pedal.Analyzed the reasons for selecting braking intent analysis parameters and thereasons for putting forward the fuzzy recognition method, then designed the fuzzycontroller, including the establishment of the membership function, determining thefuzzy rules, the precise method and the inspection of the fuzzy controller. Established the model of braking intention recognition in Matlab/Simulink, executed brake intentionrecognition simulation, analyzed different braking intent simulation results, whichshowed that the method of fuzzy recognition is effective.Finally, built the test platform of brake-by-wire pedal device, simulated the brakingprocess, acquisited the brake signal by dSPACE data acquisition system, processed andanalyzed test data. Verified the brake-by-wire pedal meet the needs of the brakingrequirements, the proposed fuzzy recognition method can effectively achieve thebraking intention recognition.