Study On The Kinematic Synergies And Muscle Synergies Of Stable Human Walking Under Different Ground Conditions

Walking is one of the most common and major forms of exercise in daily life,and the importance of its stability cannot be overstated.As a rare bipedal standing mammal in nature,two-thirds of the mass of the human body is located two-thirds of the body height from the ground,and structurally the human body should have a strong motor instability.However,in real life people show extreme walking stability,even under a variety of complex ground conditions,and this paradox has attracted a lot of attention from researchers.It has been found that the human body adapts to changes in ground conditions by changing the motor characteristics of the lower extremity,where changes in motor characteristics are directly dependent on changes in the movement of the joints of the lower extremity,which in turn are jointly determined by the activation status of the relevant drive muscle groups at each joint.In addition,it was found that there are certain similarities and regularities in the locomotor characteristics,joint movements and muscle activation behind the body of different individuals facing the same ground conditions,but there is still a lack of precise and quantifiable results on the specific changes of joint movements and muscle activation in the lower limbs under different ground conditions,and whether there are some common patterns in the stable walking of the human body under different ground conditions.To this end,this paper collects and processes the motion information related to the human body when walking steadily under different ground conditions,and answers these questions by analyzing and comparing the results obtained.The related results are expected to provide a theoretical basis for rehabilitation training of patients with impaired motor ability and the design of wearable exoskeletons.The main work of this paper is as follows.(1)Combining the relevant regulations of anatomy and the physiological structural characteristics of the lower limbs,the lower limb motion coordinate system is established,and the corresponding gait characteristics,each joint motion and driving muscles during walking are briefly introduced.At the same time,the above elements are integrated to determine the experimental paradigm of this paper.(2)The common patterns hidden in each joint movement and muscle activation were extracted by factor decomposition.The results show that there is some synergistic pattern in the changes of each joint movement and muscle activation,including co-activation and synergistic effect.By calculating the correlation between the corresponding synergies,it was found that the human body shares a set of motor synergies under different ground conditions and that most of the muscle synergies do the same,so that the human body reduces the complexity of motor realization by recruiting similar synergies.(3)To investigate how the human body achieves stable walking under different ground conditions.Firstly,the movement characteristics and the movement and muscle synergy rules under each ground condition are elaborated,and the effects brought by different ground conditions are analyzed by comparing with each other.In addition,the results also show that the human body mainly responds to the interference of different ground conditions by adjusting the hip and ankle joint movements.(4)A simple attempt is launched for the application of the obtained laws.A motion scaling mechanism is designed based on shared motion synergy,which can relatively well reconstruct most of the joint motions under different ground conditions.A motion recognition algorithm based on muscle synergy is proposed and compared with the current SVM-based motion recognition method.The results show that the method can improve motion recognition accuracy while reducing the complexity of data processing.