| Hip-assisted exoskeleton robots for the elderly have been a research hotspot in recent years.Studies have shown that providing assistance at the hip joint can effectively reduce the energy consumption and leg muscle force output when walking for the elderly and other people.Research on skeletal robot assisting elderly people to walk with balance.This project integrates exoskeleton robot technology,human kinematics,bipedal balance walking theory,gait analysis,multi-sensor information fusion and other technologies.Mechanism and sensing system design,research on hip exoskeleton-assisted balanced walking control strategy,research on balanced walking disturbance system with multimodal perception system,and balanced walking-assisted hip exoskeleton experimental research".The hip exoskeleton robot can effectively deal with the problem of unexpected imbalance of human walking.Aiming at the problem of imbalance of the elderly in the process of walking on level ground,a flexible joint-driven four-degree-of-freedom hip exoskeleton robot is proposed to assist the wearer to adjust step width,step length and step frequency in real time to maintain balanced walking during walking.A series elastic drive mechanism with clutch function is designed as the driving joint,and the free switching between the assist mode and the zero-force mode is realized by the on-off of the clutch.At the same time,the series elastic drive ensures the compliant interaction between the exoskeleton and the wearer and good force control ability.The exoskeleton integrates a sensing system including torque sensors,joint angle sensors,inertial measurement units,and a control system including controllers,servo drives,and relays,and builds a visual studio-based host computer platform for real-time perception and monitoring of the human-machine coupling system.Aiming at the problem of hip exoskeleton-assisted balanced walking control,firstly,the displacement and velocity of the human body’s center of mass during walking are calculated according to the established human-machine coupled kinematics model,and the system is simplified to a linear inverted pendulum model to evaluate the motion state.Secondly,a balance state evaluation model is established based on the instantaneous capture point theory,and the balance state evaluation of the human body is realized by judging the positional relationship between the instantaneous capture point and the support range of both feet.Finally,according to the stepping strategy in the human body balance strategy,the magnitude of the external driving force when the human body is unbalanced is calculated through the relative position of the human body center of mass and the instantaneous capture point,so that the exoskeleton can assist the wearer to adjust the step length of the swinging leg to recover during walking.In order to study the relationship between external disturbance and human walking gait,a multi-sensor fusion gait disturbance and perception integrated platform was built.The purpose of the perturbation provided by the wearer’s walking.A perception system with inertial motion capture instrument and force feedback sensor was established,and the simplified five-bar model of the human body was used to analyze its kinematics,and the platform performance and balance evaluation model were experimentally verified when the experimenter stood and walked.The use performance and balance assistance effect of the exoskeleton system were studied through experiments to verify the beneficial effect of exoskeleton in assisting the elderly to balance walking.The exoskeleton modular flexible drive joint experiment was carried out,the output characteristics of the joint were analyzed,and it was verified that the exoskeleton met the design requirements of output bandwidth and output torque.Carry out the external disturbance experiment in the walking state,and preliminarily verify the effectiveness of the balance evaluation model.The exoskeleton assisting experiment was carried out in an unbalanced state,and the experimenters were subjected to forward and backward and lateral disturbances when walking,which verified the effectiveness of the exoskeleton in restoring the human body’s balance and walking. |
