| In recent years,facing the problems of rising labor costs,changes in the operating environment and the aging society’s increasing problems,industrial robots have become more and more important in the modern development process,because they can replace humans for complex and dangerous work.The key to precisely control industrial robots is to accurately measure the robot’s posture in real time,MEMS gyro sensor technology has become a hotspot in the research field of robot attitude measurement as an autonomous attitude measurement method.This paper analyzed the working principle and method of MEMS gyroscope technology,studied the read circuit of small capacitance signals,compared differential modulation MEMS gyroscope detection circuit and ring diode detection MEMS gyroscope front-end circuit,developed a MEMS gyroscope attitude measurement system.The main research contents are as follows:(1)The micro signal read circuit of the capacitive MEMS gyro is studied.By analyzing the typical structure of the detection circuit and comprehensively considering the performance and other factors of the circuit,a differential modulation circuit mainly based on a charge amplifier is selected as the signal readout module,further studied the working principle and circuit characteristics of the circuit’s differential modulation,signal demodulation and amplification filtering modules,optimize the circuit from the aspects of component selection,parameter setting,circuit simulation,etc.A MEMS gyroscope detection circuit with differential modulation technology is designed.(2)The front-end circuit of MEMS gyroscope based on ring diode capacitance detection technology is studied.First,compare the traditional capacitance detection and ring diode detection methods,select a ring diode circuit with simple circuit structure,low power consumption,and easy integration to complete the capacitance detection.By building a mathematical model of the ring diode signal readout circuit,the influencing factors of the output voltage are studied and the filter amplifier circuit is analyzed.The front-end circuit of the MEMS gyroscope for ring diode detection is designed.(3)MEMS gyroscope attitude measurement system is developed by the method of this paper.By analyzing the two front-end signal readout circuits,a better analog front-end module is selected as the attitude measurement system and combined with the drive and detection control module based on FPGA,a MEMS gyroscope attitude measurement for industrial robots is designed and implemented system.The experimental results show that the zero bias and scale factor of the developed system have been improved. |
