Development Of Inductance Sensor Signal Acquisition System Based On USB

Inductance sensor has high resolution, good sensitivity, good repeatability and long lifespan, so it is widely used in precise measurement fields. The inductance sensor signal acquisition system is the key part of the whole measurement system, so its design level determines the precision and stability of the measurement system.In this paper, at first, the development state of inductive displacement transducers and data acquisition systems is analyzed. And then, against the problems of the existing system, an inductance sensor signal acquisition system based on USB is developed for the purpose of improving the accuracy and adding USB interface to realize data communication between the system and the computer. And therefore, the system uses more convenient.The work as follows is finished. The inductance sensor signal-processing circuit and data acquisition module which uses P89C61X2BA as main control unit are designed and developed. The data acquisition module includes A/D conversion circuit and USB interface circuit. The firmware, USB device driver and PC application program are developped. Firmware controls USB communication and data acquisition and it is developped with Keil C51. USB device driver provides assurance for the communication between the system and PC, and it is compiled with Visual C++ 6.0, DriverStudio3.1 and WinXP DDK. The application program is the interactive interface for users and the system, which is designed in Visual C++ 6.0 environment.The USB interface function experiments, stability experiments, repeatability experiments and contrast experiments are done at the end of the paper.Experimental results show that the system can transfer correctly, and it has high stability and reliability. It has advantages of portability and plug and play, and it satisfies the function needs.