Study On Gait Trajectory And Motion Coordination Of Biomimetic Exoskeleton

The lower limb exoskeleton(LLE)robot is a multi-input and multi-output wearable human-machine coupling system,which is composed of human body,mechanical structure,sensing equipment,execution unit and computing center.This cross-discipline product is used to realize the coordinated movement of man and machine,and achieve the purpose of extending the limit of human function and sensory dimensions.LLE is widely used in various fields,especially in the military field and civil defense rescue and disaster relief.The powered exoskeleton combines the human intelligence with the power of the mechanical exoskeleton to form a augmentation device with human intelligence as the core control,thereby realizing the extension of the human sensory system and the improvement of bodily functions.In this paper,start from the structural design of the power exoskeleton system,the information sensing of human-computer interaction,the collaborative motion planning strategy,etc.,the comprehensive use of design and manufacturing,simulation analysis and experimental verification methods are used to research and analyze the power exoskeleton.(1)Human-machine coupling gait trajectory optimization based on genetic algorithm.As the definition of physiology,the physiological structure of the lower limbs of the human body,the degree of freedom of the joints,and the range of motion of each joint are analyzed.From the perspective of ergonomics,the configuration design of the human-machine coupling system is carried out,and a double-chain rigid body model with a human lower limb kinematic chain and a dynamic exoskeleton kinematic chain is established for simulation analysis.The gait simulation experiment of the man-machine coupling system is designed in the multi-body virtual simulation environment using a genetic optimization algorithm.(2)Plantar pressure sensing system based on the photoelectric sensor.The modular pressure sensor is designed with the through-beam light sensing technology,its structure is novel,and no additional operational amplifier is needed in the sensing acquisition circuit to capture the sensing signal.Combined with a specially designed programmable control calibration instrument,a characteristic evaluation experiment was carried out on the modular pressure sensor.Based on the analysis of the plantar pressure distribution area,two different plantar pressure acquisition sensor layout schemes were formulated,and combined with the dynamic walking experiment,the performance of the manufactured flexible sensing insoles in the application of plantar pressure acquisition was evaluated.(3)Multi-mode movement gait phase recognition.The insole sensor system based on the plantar pressure information collection of the FSR sensor unit has carried out multiple sets of exercise gait data collection experiments with different motion rates.According to the characteristics of gait data,multiple gait phases in different motion modes are defined.Through the neural network model,the gait phase recognition is carried out without manual intervention to select the relevant signal characteristics,and the accuracy of the gait phase recognition model is improved by adjusting the network structure during the experiment.(4)The joint angles of the exoskeleton of the lower limbs move together.Establish a separate scheme of exoskeleton sensing system and power execution system,and study the joint angle coordinated movement of the lower extremity exoskeleton manmachine system.The mapping relationship between the sensor set and the rotation angle of the human body joint is calibrated by specifying the action.A method based on the LSTM model is proposed,which uses the real-time data of the dynamic exoskeleton during joint cooperative motion to predict the motion trajectory,and evaluates the results of the joint trajectory prediction experiment.(5)Exoskeleton design based on ergonomics.According to the theoretical analysis and research work,the hardware system and its corresponding physical objects designed in the process of the subject research are given,including bionic exoskeleton configuration design and simulation analysis,ankle joint actuator design and power lower extremity exoskeleton system prototype.Starting from the overall design requirements of human-computer interaction,structural design,and range of motion,combined with the selection of actuator schemes and the analysis of processing materials,a modular exoskeleton prototype system platform was developed.