The car has various problems which is the traffic accident, congestion, pollution, and the resource consumption, etc. However, recently the realization of AHS (Automated Highway System) which is one of ITS (Intelligent Transport System) is enumerated as an effective solution of these problems. This paper describes the effectiveness of the discreat-time sliding mode control system in the simulation and the experiment. Two radio controlled cars of 1/10 scales on the market are used for the experiment device. The radio controlled car is autonomous because it is equipped with the microcomputer which printed out the program of control system, ultrasonic sensor for measuring the distance between cars, and the photo transistors for steering wheel control. It makes two radio controlled cars ran by steering control on the oval course. The distance between cars is observed by VSS observer. And this paper verifies it's effective.