Research And Design Of High Precision Ultrasonic Distance Measurement System

With the rapid development of China’s economy and society, Technological level of automation Continuously improve, various types of industrial control, intelligent barrier, intelligent robotics, industrial automation, and other fields of high-precision ranging proposed strict requirements. However, the traditional ultrasonic range finder is due to their own limitations and can’t meet the needs of some applications, which prompted us to want to develop a higher range precision equipment.In the theoretical analysis phase, this paper Conducted the various methods of traditional ultrasonic ranging theoretical analysis and comparison, based on the design complexity and cost factors, selected time difference method as the basic measurement principle difference of this system. Since the temperature of ranging error seriously affected, increasing the temperature detection module, real-time detection of the ambient temperature in the system, and ranging system for temperature compensation. System used ultrasonic sensors as an independent system front, and40K Hz pulse as the launch drive. System uses Xilinx’s FPGA chip as the main chip ranging system, through the actual transmitter circuit, the receiver circuit and measurement algorithm has been improved to achieve a high precision distance measurement, LCD monitor can display real-time distance measurement. After the system boot, in real time measured distance, measured once every0.1s, measuring five times the mean time taken for display. In order to facilitate the application of system expansion, increasing the serial communication module can be collected in real time temperature and distance values uploaded to a computer or other embedded devices.System design is described from three aspects, including hardware design, software design and scenario testing. In hardware design, first introduced selection system components, and then introduced the ultrasonic transmitter circuit design, ultrasonic receiver circuit design, the temperature acquisition circuit design, system design, display module and so on. In software design, first from the system perspective, analyzed of the various functional modules composing software, then one by one functional module detailed design, made simulation, and so on. In the system actual scene testing phase, mainly combined hardware structure, build a test environment, then made the actual hardware tests from three test scenarios, including long-distance ranging test, a short distance away from the test, plus obstacle distance test. The system measuring accuracy is less than2mm, blind area3cm, the maximum range of200cm.