Automotive Adaptive Cruise Control System Preliminary

With the development of highway's building in our country, the car-collision on highway takes place frequently, which brings numerous losses to the property of the country and the people. To avoid car collisions on highway, Auto adaptive cruise-control system is introduced in this paper. The conditions of the road in front of the car can be kept watch on by this system continuously. Before the dangerous circumstance happen, a warning signal will be sent to the driver by the system in time,which can make the driver have enough time to take effective measures and avoid collisions.To finish the task of distance measuring, speed measuring and warning, the theory of laser-based distance measuring is used in this system, and the system is controlled by SCM (Single Chip Microprocessor). To ensure the precision of distance measuring, the high-speed laser driving circuit and the detect-amplifying circuit constituted by two class high-speed operational amplifiers are used in Auto adaptive cruise-control system, and the laser flying time is measured by a sixteen bit's binary counter , whose counting frequency is 100 megahertz. To reduce the consumed power of display circuit, the special display driver--PS7219 is used in display circuit of this system. To make the system work normally, 12 volts' positive voltage is converted into 5 volts and ±6 volts by power supply unit, in which 5 volts is provided for digital circuit and ±6 volts is provided for analogue circuit. The design of software includes 10 programming modules and 5 subprograms, which finish the work of threshold setting, distance computing, signal processing, alarming and so on. Through the run of distance processing module, the system can distinguish the objects in front of the car, barrier on the roadside and the objects on the ground, and provide bases for alarming. In this paper, the developments of Vehicle anti-collision technology in the world, the meaning of study, the main content of study and the total designing project of thissystem are introduced at Chapter 1, the design of circuit of this system is introduced at Chapter 2, the design of software of this system is introduced at Chapter 3, experimental project and result of this system are introduced at Chapter 4.