Research On Data Acquisition And Transmission Of Lower Limb EMG Signals Based On FPGA

Rehabilitation training is a great approach to recover and improve movement ability of those disabled people. Traditional rehabilitation methods are based on the manual training from therapist which is of low efficiency, making it difficult to meet the demand of the rehabilitation. The aided-robot rehabilitation based on electromyography(EMG) control can process the collected information to identify human’s intention to control the movement of the robot, and to achieve the goal of the rehabilitation training through taking the body to move.The premise and basis of achieving the function of robot is to collect the useful EMG signals, which is the resource signal of the aided-robot rehabilitation for controlling. As the EMG signals are always weak and subjected to noise, it will obtain great significance to design an EMG signal collecting platform which can be convenient to collect the effective EMG signals with stable performance.This paper designs a platform for the collection and transmission of the EMG signals which is featured by low cost, convenient operation, high precision of data acquisition, excellent real-time performance and multi-channels’data acquisition based on the virtual instrument theory, according to the functional demand of the aided-robot rehabilitation and the character of the EMG signals. First of all, the paper analyzes the functional requirements of the platform and the characters of the EMG signals. According to the guidance of the virtual instrument theory, we have designed a fundamental framework of the platform, including the modules of signal regulate circuit, data acquisition circuit, data transmission interface circuit, PC software etc., Second, suitable chips are chosen to establish the mechanical structure of the platform’s data acquisition. This part introduces the design of the signal regulate circuit, the data acquisition circuit is based on A/D, the data transmission interface circuit is based on PCI9052and the logic control circuit is based on the FPGA, realizing the control of the data acquisition circuit and the communication between the acquisition circuit and the data transmission circuit. Then, the PC software is designed. It includes the research of the driver program and the design of the application software, realizing the software-control of the acquisition device and the procedure, making the device "virtualization".With the successful realization of each module, the thesis introduces the design of the data acquisition circuit, data transmission circuit, the logic control circuit and the application software. And at last we made a series of experiments of the EMG signals acquisition to test the system and prove its practicality overall.