Abstract:

In order to increase the security of coaches,the paper proposes a coach security system with overload prevention and anti-collision based on single-chip microcontroller STC89C52.The design is realized by studying the principle of ultrasonic ranging and pulse width modulation and monitoring the weight of the vehicle and the distance of the obstacle.Finally,the safety and precision of the system are tested.The experiment result shows that the system meets the requirement.

Key words: ultrasonic ranging;microcontroller;weighing sensor;pulse width modulation