Research On A Car Reversing Radar With Utrasonic Ranging And Its Intelligent Node In Vechicle CAN-bus

Today, most of car reversing radars using ultrasonic ranging principle and MCU intelligent technology, are widely used in the field of automotive electronics. Most of them operate only as an independent control unit, and are unable to be connected to the CAN networks of vehicle. Researching on the ultrasonic ranging, hardware and software design of the car reversing radar, this paper designs a CAN-bus intelligent node, to realize the data communication and resource sharing with other intelligent nodes.The main works completed by the author of the paper include:1. This paper investigates the present level and progress of the car reversing radar. By introducing the development and theory of ultrasonic ranging, also the theory and characters of ultrasonic sensor, the paper proposes the system general structure based on its function. Then introducing in two parts:car reversing radar and its intelligent node based on CAN-bus of vehicle.2. The parts of car reversing radar consist of three modules:ultrasonic emitter and incept module, control module and display-alarm module. It presents the design of the hardware and software based on the MCU PIC.3. The system is simulated with MPLAB-IDE and Proteus. The software design is completed by utilizing machine language and MPLAB-IDE. The results and error analysis of the experiments is presented.4. An intelligent node of can-bus for the car reversing radar is designed, using the MCP2510 CAN controller and the TJA1050 CAN transceiver, so that the radar can be integrated with the CAN networks of vehicle. Then, the paper gives the CAN-bus interface circuit, as well as communication messages and software design, combines with interpolation operation to improve precision of message. Its feasibility is verified by experiments.5. Both the hardware and software design of the car reversing radar which based on ultrasonic ranging and CAN-bus of Vehicle, has completed, so as the system debugging. The results of experiments show that, the design is able to reach the anticipated technical indicator and has higher precision and stability. The issue offers the foundation for the car reversing radar designing, and has broad application prospect and practical value in the communication messages design, so as the extension of vehicle CAN networks.