Wang Rencheng

Study of Multi-Freedom Myoelectric Prostheses with Tactile Sense

This paper designs a bionic artificial hand that has a tactile sensing, two degrees of freedom, driven by surface electro-myography (SEMG). The tactile sensor applying PVDF as a sensitive material, fitted the finger of artificial hand, has a good dynamic response. The tactile sense is spread to the user by an electric shock generator. Using improved power spectrum ratio and data fusion method based on statistical decision-making of Bayes, the movements of hand are recognized from SEMG. The experiment proves that it is a good way that the hand is controlled by SEMG combining with tactile sensor

Control strategies and topological invariance of human prehension

Control strategies and topological invariance of human prehension are discussed through the analysis and comparison of upper-limb reaching-grasping tasks. Five subjects were asked to perform different reaching-grasping tasks with different indices of difficulty, and the movements were captured using a Vicon 3D motion analysis system. Topological invariance was observed in the trajectories of different task performances. After normalization, the trajectories of the hand had very close patterns for different reaching-grasping tasks. Synergy control in the reaching-grasping movements of the upper limbs was also found among the different joint angles. Despite joint redundancy, the joint angles can be fitted using the same format of functions proposed in this study. The parameters in the function can be taken as a characteristic feature of reaching-grasping movement patterns.