Research On Key Technologies Of Non-contact Torque Measurement

In mechanical transmission, the torque is one of the most important parameters of a variety of mechanical characteristics. And torque testing is one of essential contents of mechanical product development, quality inspection, optimal control, condition monitoring,fault diagnosis and so on. Torque sensors have been widely used in optimization and intelligent control in power-driven systems of various machineries, such as motor vehicle engine testing and motor factory testing.Firstly, in this paper, the course of development and the current research of torque sensors at home and abroad are carefully analyzed and summarized. On this basis, the basic principles of torque measurement are studied. The torque value can be calculated by measuring the deformation of the resistance strain gauge pasted on the elastic shaft. Non-contact torque measurement instrument is designed in this paper based on the signal and energy transmission of wireless ,which leads to the solve of the problems such as the friction existing in contact area , the wear and tear, heat of contact parts and other issues in traditional cable transmission.Secondly, the torque signal processing program is designed. In the rotor circuit, the weak signal output from the strain bridge is amplified through the instrumentation amplifier AD620, and then through a second-order Butterworth low-pass filter, then converted to digital signal by A/D module the CC1110 chip through A/D conversion, and then the figures obtained is shoot out by the wireless transmission module of CC1110; after the wireless receiver module of CC1110 on the stator received the torque signal, on one hand, the information is displayed on outer LCD module 12864, and on the other hand it can communicate with the host computer through serial interface 232.After the hardware was completed, the software is also designed, including RF wireless transmitting and receiving of torque signals, real-time LCD display of torque.Thirdly, in order to ensure rotary circuit of non-contact torque measurement can normal running, a inductively coupled power transfer system(called ICPT for short),using a single power MOSFET as resonant converter, is presented in this paper. This is realized with a detachable and ironless high frequency transformer. Furthermore, This paper makes use of state space model analyzes the equivalent circuit. Experimental results show that this model is precise enough to analyze the equivalent circuit and this system is suitable for cordless power supply for non-contact torque measurement. At the same time, it also use for reference for future similar project.Finally, the paper discusses the system's anti-jamming measures. First of all,the possible interference and noise, including it's means of transmission, is analyzed in this paper. Therefore the hardware anti-interference methods, including shielding, filtering and grounding are discussed. At the last, two kinds of software implementation of anti-interference methods are presented. one is to prevent interference of microcontrollers, and the other is digital filtering.