Acquisition System Design Of Human Lower Limbs Motion Information

Lower limb rehabilitation robot is medical equipments of rehabilitation training.It combined with lower limb exoskeletons robot technology and rehabilitation trainingtechniques, and service to the hemiplegia or the lower limbs impediment. To achievethe purpose of rehabilitation training, it need to real-time detect some necessarymotion and mechanical parameters used for rehabilitation robots gait and the attitudecontrol, and the human lower limbs joints motion information is the most directlykinematics parameters can reflect the state of human body gait motion.In order to get close to information of the human lower limbs motion rules,achieve a higher compatibility requirements, more appropriate human body motionrules of lower limbs rehabilitation robots design and research，a plan of multi-channelinformation acquisition of the human lower limbs joints motion is put forward. Basedon FPGA technology, USB2.0interface technology and LabVIEW technology, a set ofdata acquisition system is designed referred to as “human lower limbs motioninformation acquisition system”.The system includes mechanical system and data collecting system. First of all,by the wear way the tester and mechanical system is linked together. And then, bythe sensor (photoelectric encoder) connected mechanical system and data collectingsystem as a whole. Finally, realize the motion of lower extremities test informationcollection and processing.Mechanical system includes lower limbs follow-up mechanism, weight lossdevice and treadmill. The follow-up mechanism design is the focus of mechanicalsystem, using the configuration scheme of the lower limbs six rotational degree offreedom. Hip two degrees of freedom, knee joint a degree of freedom, realizeflexion/extension and adduction/abduction of the human hip, flexion/extension of theknee, and developed a prototype system and the experimental analysis.Data acquisition system includes: the data acquisition and processing part withencoder and FPGA primarily, the data transfer and storage parts with USB interfacechip and PC primarily. Detailed introduces the software design and hardwarerealization of the FPGA module and USB communication modules, and gives thesystem test and experiment results.By the hybrid model of engineering design method,efficiently realize the FPGA program design. Ensure the reliability of the system, andshorten the development cycle. The experiments show that the system can achieve multi-channel synchronousinformation acquisition and processing, data real-time display and storage. There arethe characteristics of high performance, low power consumption, multi-channel, easyto expand. It provides an effective data analysis and processing of the experimentalplatform for lower limbs rehabilitation robots design and development, and can getbasic data that will suitable for human motion state.