Design Of The Test System For Electrical Performance Of A Potentiometer

Potentiometer is an electromechanical conversion component, whose work status is related with the relative position of the moving contact and resistance; it can be widely used in control systems, electrical equipment, aerospace and other technical fields. Potentiometer, as an important component, its electrical performance (include the total DC resistance, the effective electrical travel and independent linearity, electrical continuity, output smoothness, contact resistance, backlash, sine response) is the insurance to keep each system work properly. Therefore, it is necessary to test its electric performance parameters during the developing and producing process of a potentiometer.For the request of the potentiometer's test methods for electrical performance and related technical specification, this article developed and studied a comprehensive test system for the potentiometer's electric performance. The test system was designed by the motion control technology, virtual instrument technology and combined the related algorithm of signal processing. Firstly, the overall design plan for this test system was introduced, including the system's technical requirements and potentiometer's testing principle of electrical parameters. Secondly, hardware design was introduced. Hardware consists of the motion control unit, the data acquisition unit, signal processing unit and hardware layout. The motion control unit is implemented by the motion controller to conduct the servo motor into high precision rotation, the motor drives the potentiometer into corresponding actions, and then we can reduce errors by adjusting the PID. The data acquisition unit was implemented by AD device, it can gather output signal of the potentiometer. The signal processing unit was implemented by some circuit boards, it can accomplish the electrical parameters testing module's switch. Finally, software implementation and data analysis were introduced. The software implementation was based on the LABVIEW platform. The design method of electrical parameters in each test module was introduced in detail, a friendly man-machine interface was designed, and the PC can communicate with the digital device. Finally, we can get the test results through the processing and analyzing of the signal.This system has been put into use successfully. Testing results show that the accuracy of the test system can meet military standard requirements and the engineering requirements; moreover, the system realizes the character of high precision and high automatio.