Automotive Infrared Laser Smart Anti-collision Device

With the development of society economy in our country, the highway traffic tends to drive high speed, flow intensively, pilot nonprofessionally. Traffic safety also becomes more and more important for social problem, which caused widespread concern with society and government. It is a valid measure for traffic safety in our country to develop the intelligence transportation system and the intelligence vehicle.Firstly, this thesis gives present application instance of the intelligence vehicle's technique in auto anti-collision. Then under the condition of our country's superhighway, driving habitually and the existed technique of the feeling machine, designed the anti-collision device with red laser-based which adapt to the highway and the situation of our country. This device fixed to the vehicle forepart, which is keeping on scouting this car and former car. Before an accident occurs, this device gives an alarm to remind pilot to decelerate or apply a break, which can avoid the car tail collision effectively.According the basic function of this system, after contrasting the four familiar methods of distance measuring, finally build up a system project with the theory of red laser-based distance measuring. After analyze how to distinguish from the front target and fencing, design some application circuits, such as the power supply, information collection, keyboard/display, man sound alarm etc. 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. 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 resource consumption of software and hardware, the serial intelligence keyboard/display control chip-HD7279A is used in keyboard/display circuit of this system, which is simply and application convenience. To raise the man voice effect, the API and twenty one second voice chip-AP8821 is used in the system.