As electric technique develops fast, steering system changes from conventional mechanic steering system to Hydraulic Power Steering (HPS). Flowing HPS, Electrically Controlled Steering (ECS) system, including Electric Power Steering (EPS) system, Active Front Steering (AFS) system and Steer-by-Wire (SBW) system. ECS makes it easy for a driver to control a steering wheel using a less torque at a low speed, which is usually called steering portability Besides, ECS could also help a driver steer a vehicle stably at a high speed, which is usually called steering stability ECS provides an optional method to solve the contradiction between steering portability and steering stability. [1] [2] The study of ECS involves mechanic design, detection of electric components, software design and so on. Researches of ECS need a lot of trials and errors. By now, the development of ECS mostly depends on experiments on Hardware-in-the- Loop (HIL) and real vehicles. Because tests on real vehicles have many shortcomings, such as a higher cost, a longer period, etc. HIL is gradually taking the place of real vehicles to carry out kinds of experiments in order to reduce test times, cycles and costs, which has been a main means to research and develop ECS.
In this paper, it proposes a project about a hard-ware-in-the-loop test-bench based on dSPACE real-time simulation system. It consists of hard-ware and soft-ware. Hard-ware includes a single-board system, namely DS1103, Micro Auto Box II and a steering system of a real car. And soft-ware is based on MATLAB/Simulink and CarSim. They help build models of EPS controller and the steering resistance. Besides, it also uses Control Desk to design human-computer interface in the paper. It simulates test conditions of real vehicles on test-bench then detects the validity of EPS controller algorithm, compared with tests on real vehicles. Results of tests on HIL are almost accordant with those of tests on real vehicles, which prove the designed test-bench valid for other electrically controlled steering systems. The test-bench that is effective works well in researching and developing ECS. As EPS is a typical representative of ECS, it is advisable to use EPS as a prototype.