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To improve the interface bonding strength between the substrate and phases in the Ag-based composite, the silver-coated NbSe2 and silver-coated Ti0.09Nb0.91Se2 particles were synthesized by chemical reduction method, and the Ag-based composites were prepared by powder metallurgy. The results show that, the silver particles are uniformly distributed on the surface of the transition metal selenides, and the Ti0.09Nb0.91Se2 particles show the better coating effect. After covering the Ag coating, the contact between the transition metal selenides and the metal matrix silver is increased, leading to the better wettability and the smaller repulsive force between Ag and the transition metal selenide. Moreover, the possibility of the transition metal selenide decomposition in the Ag-based composite materials is greatly reduced after the Ag coating. The densification of the Ag-based composite materials is improved and the interface bonding strength between the Ag substrates and the transition metal selenides is enhanced. Compared with the Ag-based composites with the uncoated NbSe2, the friction properties of the Ag-based composites containing the silver-coated transition metal selenides decrease slightly.

In order to improve the automation degree of the massage robot,the structure design and kinematics analysis of a four fingered,motor-driven robotic hand for massage robot is completed. Each finger has two joints: the first joint and the second joint. And the degree of freedom of the hand is four by connecting the first joints and second joints of index finger,middle finger and ring finger respectively. In addition,the crank-rocker mechanism is creatively adopted to driven the second joint,which is conducive not only to enhance the continuity and the periodicity of pinching manipulation,but to also avoid frequent reversing the rotation of motor,prolonging the service life of the motor. At last,to verify the design,the model of dexterous hand is developed. The rationality and feasibility of the mechanism of hand are proved by ADAMS motion simulation and MATLAB numerical analysis.