| After a stroke,the body often shows a lack of muscle strength and muscle atrophy in the lower extremities,making it difficult to achieve regular limb movements.Research has confirmed that frequent and regular rehabilitation is effective in treating lower limb muscular atrophy and can help restore body movement,gait balance and muscle coordination.Currently,rehabilitation is often carried out in hospitals or rehabilitation centres,which increases the financial burden on people.Commercially available lower limb rehabilitation products focus on limb movement rehabilitation,neglecting the connection between the product and the patient’s brain cognition.Training products for lower limb rehabilitation in stroke are too modular and mostly mechanical,lacking a sense of identity,are bulky and difficult to operate,are boring and do not have clear phases of rehabilitation,and do not allow patients to know what is happening during lower limb rehabilitation in real time.This paper takes the human lower limb joints as the main object of research,and incorporates visual movement trajectory effects and real-time training evaluation into the lower limb rehabilitation training process to assist patients in understanding their lower limb rehabilitation status in real time.Three modes of lower limb trajectory training are provided for users,and the value of visual perceptual theory-guided limb trajectory experiments in lower limb rehabilitation training is demonstrated.Finally,a lower limb joint assistive device that can be guided by trajectory-assisted movements is designed to assist patients in lower limb trajectory training.The details are as follows:(1)Through the study of the theory of visual perception,the analysis of lower limb muscle strength rehabilitation in stroke and the physiological movement characteristics of each joint of the lower limb,it was interpreted that the trajectory-assisted guidance of limb movement has good training effects on the muscle strength recovery of the lower limb,and three modes of lower limb trajectory movement,namely passive training,active training and combined active-passive training,were proposed respectively.Through somatosensory interaction and myoelectric sensing technology,an experimental platform for muscle activity of lower limb rehabilitation training based on surface muscle electrical signals was built.The muscle activity of lower limb muscles in the rehabilitation training with the feedback of visual-perceptual movement trajectory was detected to be more variable,which proved the feasibility of the visual-perceptual movement trajectory mode and could realise the lower limb movement trajectory training.(2)The Kano model was used to accurately reflect the practical needs and problems of users for lower limb rehabilitation products,and the hierarchy of functional needs was divided into basic needs,core needs,undifferentiated needs and desired needs to prioritise the needs of lower limb rehabilitation equipment,resulting in a hierarchy of priority needs in terms of human-machine and lower limb rehabilitation aids.(3)The Siemens Tecnomatix Jack software was used to analyse the relevant real-time data generated during human movement,to collect the standard movement trajectories of human lower limb limbs,and to use the resulting changes in lower limb joint movement angles as the standard movement trajectory planning scheme.The equations for the motion trajectory hip and knee joint parameters were listed for the planning of the lower limb rehabilitation trajectory and the structural design of the lower limb rehabilitation aids was carried out.Through MATLAB experiments and analysis,the smoothness of the transition of the planned trajectory was verified,and the planning of the lower limb rehabilitation training trajectory was completed.(4)Design solutions were proposed for the appearance and structure of the entire rehabilitation device as well as the interface display.The 3D model of the product was constructed through the solutions,and the final chosen solution was optimised and rendered with effect drawings.The developed rehabilitation device consists of an assistive device actuator for lower limb flexion and extension activities and a visual display device.Combined with the experiments on the effectiveness of the visual-perceptual guided movement trajectory and the rationalisation tests on the structural trajectory planning of the lower limb assistive device presented in Chapters3 and 4,good desired results can be achieved,verifying that the lower limb rehabilitation assistive device designed in this paper is feasible,operates smoothly and can provide effective rehabilitation training for patients. |
