Lower limb rehabilitation robot compliance control method based on variable admittance

Abstract

The invention discloses a lower limb rehabilitation robot compliance control method based on variable admittance. The control method comprises the following contents of synchronously acquiring surfaceelectromyogram signals and motion information of an uninjured side lower limb and an affected side lower limb of a patient via a Delsys electromyogram acquisition system and motion capture equipment,in cooperation with a plantar pressure sensor, acquiring human-machine interaction force between a lower limb rehabilitation robot and the patient via a plantar pressure sensor, and acquiring lower limb motion intentions of the patient through information fusion; establishing a human body lower limb musculoskeletal model via OpenSim software, calculating out muscle strength values of related muscles of lower limb flexion and extension motions, and in combination with an affected side mirroring uninjured side method as well as a GS-LSELM algorithm, establishing an electromyogram-muscle strength identification model of the human body lower limb and identifying out a muscle strength value of the affected side lower limb; and establishing a variable admittance model based on muscle strength torque and deviation away from an expected joint trajectory of the lower limb rehabilitation robot so as to correct the expected trajectory, and calculating deviation in combination with an actual trajectory and inputting the deviation into a position controller, so as to finally achieve tracking of the expected trajectory of the patient and active compliance control of the lower limb rehabilitation robot.

Description

technical field [0001] The invention relates to the field of lower limb rehabilitation robot control, in particular to a variable admittance-based compliance control method for lower limb rehabilitation robots. Background technique [0002] In recent years, the number of patients with impaired motor function due to stroke and trauma has increased year by year, seriously affecting the daily life of patients. Clinical studies have shown that through reasonable rehabilitation training, the motor function of the affected side of the patient can be recovered to varying degrees, or even cured. Traditional rehabilitation methods need to be completed by doctors, which are inefficient and work-intensive, and cannot meet the increasing rehabilitation needs of patients. With the development of robot technology, intelligent rehabilitation robots can effectively improve the recovery efficiency of patients, while greatly reducing the work intensity of rehabilitation physicians. The exis...

AI Technical Summary

Problems solved by technology

However, the above-mentioned signals are mostly used for the recognition of human motion intentions, that is, to realize the switching of control modes of rehabilitation robots; there are also researches on adaptive control methods of rehabilitation robots, but the compliance of the control process cannot be effectively guaranteed

For example, the impedance control method based on interactive force feedback lacks adaptive adjustment for different rehabilitation training stages of patients due to the fixed impedance parameters in the model, and the compliance of rehabilitation robot control is also poor.

In summary, there is still a lack of an efficient compliant control method for lower limb rehabilitation robots

Images