Comprehensive Evaluation of Human Hand Manipulability During Walking at Different Speeds

Using the experimental kinematic data of 11 healthy subjects, the kinematic manipulability of human hands during walking is evaluated. A total of 37 degrees of freedom mechanical model of the human body is used for this purpose. The forward kinematics and Jacobian of the model have been derived using the Denavit-Hartenberg convention. Experimental kinematics are mapped on the model using the inverse kinematic method based on optimization. The effect of walking speed on the profile and symmetry of manipulability for both right and left hands are studied. Statistical analysis showed that the walking speed can change the manipulability of hands and there is no quantitative symmetry between the manipulability of right and left hands. The results showed that there is more ability to create velocity for the hands-on horizontal plane than on other anatomical planes during walking. The results of sensitivity analysis showed the importance of the values of the hip and shoulder joints on the manipulability of the hands. The experimental manipulability profile of healthy human hands presented in this article can be used as a reference in rehabilitation to evaluate the effectiveness of physiotherapy as well as evaluation of hand function after surgery and also designing realistic motions for humanoids.