A Study on Safety Intelligent Driving System for Heavy Truck Downhill in Mountainous Area

摘要

Mountainous area makes up more than half of the whole land area of China, the road of which is full of ups and downs. Heavy commercial vehicles as the main means of transport in mountainous areas, braking torque recession, even brake failure, often happens because of the overheating in long downhill journey, which seriously threatens the safety of the driving. Therefore, this paper presents an intelligent assistance system based on Geographic Information System and vehicle dynamics. The main brake duration and heat generation can be effectively reduced through adjusting the speed at the slope top, applying the engine auxiliary brake in the initial stage and choosing braking strategy appropriately, in order to prolong the downhill driving distance and improve the safety during continuous braking. This paper characterizes and analyses the road gradients and their effects on braking heat generation. To analysis the temperature rising characteristics of the main brakes under different initial speeds, the temperature rise model of the brake is established. Furthermore, the effectiveness has been recognized by comparing the main brakes’ temperature variation in real vehicle test. Research shows that an apparent temperature rise reduction performance of the typical slopes is achieved in the simulation, and the test results show a better performance of reducing braking temperature on actual road.