Robust Control Of Robot Manipulator Based On Dual Quaternion

In recent years,China has been aging and has entered an aging society.And the number of patients with upper limb paralyses is on the rise due to factors such as accidents,diseases and an aging population,which has led to a significant increase in the demand for rehabilitation training.The current medical service of rehabilitation training relying on therapists is inefficient,poorly reproducible and weak in information processing.Rehabilitation training assisted by robot manipulators can ensure training intensity,efficiency and precision,provide personalized programs and increase the sense of active patient participation.The success of robot manipulator-assisted rehabilitation therapy relies on multiple factors,including the implementation of strong control strategies that prioritize accuracy and real-time responsiveness.Additionally,the interaction between the robot and the patient must be flexible and adaptable to ensure the safety and effectiveness of the training process.This thesis takes a 7-degree-of-freedom redundant robot manipulator as the research object and investigates in depth the key technologies required for the redundant robot manipulator in the rehabilitation training process.(1)Considering the simultaneous translational and rotational movements at the end of the robot manipulator in rehabilitation training,an accurate coupled description of its position and posture using dyadic quaternions,and a dynamics model based on this,does not have representation singularities,discontinuities and effectively improves the computational efficiency of the system compared to other methods.(2)To address the problems of strong non-linearity,modelling errors,friction,unknown external disturbances and unmodelled uncertainties in the redundant robot manipulator system,the uncertainty and disturbance estimator techniques are used to estimate and feedforward compensate for the total uncertainty of the system set;the accurate tracking of the desired poses is achieved by designing a sliding mode controller.After careful consideration of both control methods,a sliding mode control strategy based on uncertainty and disturbance estimator is proposed to improve the accuracy and robustness of the system attitude tracking.(3)To improve patient interaction and safety during rehabilitation training,an impedance control algorithm is investigated to correct the desired position of the system.This results in the control of the contact force at the end of the robot manipulator.To address the problem that existing variable damping impedance control is difficult to ensure transient performance,a variable stiffness impedance control framework is proposed to achieve accurate and robust control of the control force at the end of the robot manipulator while improving adaptability to complex environments and reducing the force impact generated by contact with the environment...