Research Of The Hill-Start Control Assist System On Motor Vehicles

For the phenomenon that the manual motor vehicles often slip backward when starting on the uphill, a hill-start control assist system (HAS) on manual motor vehicles is designed in this paper. The HAS is an Electro-mechanical system,it is developed and designed on the basis of the already existing automobile Anti-Lock Braking Systems (ABS), the force sensor, inclination sensor and hill-start solenoid valve are added into original brake system, and a new speed sensor for measuring low speed and direction of rotation is used.It is very easy for drivers to operate vehicles, hill-start assist for manual motor vehicles will be achieved through only pressing a button. HAS can improve safety and comfort of driving.The key technology of HAS is that HAS can automatically control parking braking force according to changes of size and direction of supporting counterforce from braking parts. HAS first obtains initial value through the force sensor, and then according to mechanical balance equation gets off the size of needed braking force which makes automobile park on the uphill and supporting counterforce critical value when the automobile need remove braking force. Using force sensor for detecting changes of supporting counterforce is the technical innovation point in the paper.The composition and operation principle of HAS is explained in the paper, according to requirement of HAS for brake structure ,the suitable brake is chosen as the rear wheel brake of automobile through relatively comparing, mechanical equilibrium equation is set up by force analysis of the brake; Considering regulation for parking slope range in our country, security and feasibility of parking about HAS is demonstrated through analyzing and calculating parking braking force imposed by HAS;The hardware and software of HAS are designed; Automobile simulation models are established and simulated, the critical point is found through simulation results so that HAS can timely remove parking braking force at critical point.Finally, this paper summarizes all work and extracts some constructive advices for the further improvement.HAS can completely solve the phenomenon that manual motor vehicles often slip backward while starting on the uphill, effectively prevents hidden danger from slipping, and has no any influence on starting on flat ground.So,the development of HAS is very great significance.