Research On Control Method Of Omnidirectional Walking Stick Robot

The trend of aging society in all countries of the world is becoming more and more serious.The number of elderly people is increasing year by year,and the number of employees in China is scarce.The employees are lack of professional skills and professionalism.Relying on the rapid development of robot technology,the development of rehabilitation assisted robots to solve the problem of lower body obstacles for the elderly to improve their physical fitness and rehabilitation has become a hot topic in the research field,and rehabilitation assisted robots started late in China,developed slowly.By analyzing related thesis and literatures at home and abroad,it is found that in the past,during the walking process of the walking stick robot,the walking stick cannot swing freely due to the vertical structure connection between the walking stick supporting part and the omnidirectional moving chassis,and the corresponding supporting force in any direction cannot be provided.The whole robot is a rigid body structure,which can only play the role of following and guiding,providing a certain traction force,and can not accurately reflect the user's behavior intention,which is completely different from the habit of the elderly using ordinary walking sticks.A corresponding study was carried out on the problem that the structure of the walking stick assisting robot and the assisting process did not satisfy the habits of the elderly.The walking process of the walking stick assisting robot should satisfy the movement rule of the ordinary walking stick,and can control the movement of the user's behavior and control the robot to make certain movement adjustment according to the change of human-computer interaction.In line with the habits of the elderly.The main research content of this thesis is divided into three parts.Firstly,in order to solve the problem that the walking stick cannot swing freely and cannot provide the corresponding supporting force in any direction,the mechanical structure of the walking stick robot is improved,and the walking stick robot supporting portion can swing freely.At the same time,according to the structure and the assisting process of the robot,the kinematics model and dynamics model of the walking stick robot are established.The kinematics model reflects the relationship between the poses of the various parts of the walking stick robot during the movement;the dynamic model of the walking stick robot It reflects the relationship between robot human-computer interaction force,driving force and motion state.The dynamic model of walking stick robot is established by Lagrangian modeling method,which provides a basis for the analysis of control strategy.Secondly,the data acquisition platform of the walking sticks movement process was built.By collecting the data of the interaction between the ordinary walking stick and the swinging angle of the walking stick,the movement law of the ordinary walking stick was analyzed,and the walking stick model was established to obtain the interaction between the interaction force and the walking stick movement.The accuracy of the model was verified.Finally,in order to make the movement of the walking stick assisting robot conform to the habit of using ordinary walking stick,the walking stick model and the force admittance model are used to control the movement of the walking stick,and the PID speed control achieves the speed following.Among them,the force admittance model converts the difference of human-computer interaction force brought by the robot structure into the movement of the robot,and the walking sticke model makes the robot's assisting process conform to the usage habit of ordinary walking stick.The effectiveness of the control strategy is verified by experiment.