Study On The Plantar Pressure Distribution Detection System For Lower Limb Rehabilitation Robot

Plantar pressure is an important biomechanical parameter of patients during rehabilitation training.At present,it is difficult to adjust the motion parameters reasonably because of the lack of plantar pressure feedback,which affects the scientific and safety of the rehabilitation training.Therefore,this paper proposes a new method which uses elastic beam's strain to detect plantar pressure for pedal-powered lower limb rehabilitation robot.The main works was as follows:A plantar pressure distribution detection system was designed and four main force bearing points were chosen as measurement point on the basis of analyses of plantar pressure;The structure of detecting device was determined through continuous optimization,especially the size,shape and location of elastic beam;a mathematical model to calculate the plantar pressure was established based on the relationship between the elastic beam's strain and the force,which was verified through the finite element analysis simulation,and the global experiment of the location of beam 1 and beam 2 was carried out.Results provide preliminary evidence suggesting that plantar pressure of main stress point can be achieved utilizing this method and device accurately by comparing theoretical calculation and simulation results.The signal acquisition system was designed and its performance was tested;results show that the margin of error is ? 0.4uv and the system can satisfy experiment requirement.The static performance of the detection system was analyzed and the calibration of the device was fulfilled by experiments.Results show that the detection error is ? 0.1%-? 20.3%,and the plantar pressure distribution can be identified through the detection system.The research work of this project will provide solid bases for monitoring the size and distribution of plantar stress in the course of low limb rehabilitation training,the evaluation of the rehabilitation effect,the identification of the strephenopodia and strephexopodia and the detection of spasticity,etc.