Model Establishment And Kinematics Simulation Of The Virtual Hand Based On Ergonomics

With the development of industry, robots are widely used. As an important part of the robot, because of its strong function and general properties,the dexterous hand can complete various kinds of complicated tasks such as production in the chemical industry, machinofacture,nuclear power maintenance,medical operation and so on.Therefore, high-performance general dextrous hand becomes the hotspot of researchers from home and abroad.Based on the analysis of researches on dextrous hand from home and abroad,this paper introduces a new type of five-finger dexterous hand,and then forward and inverse kinematics are built,finally its trajectory space is simulated.Firstly,physiological structure of people's hand is analyzed and 3D virtual hand's model is made.This hand has two Innovations:one is the structure sizes of the finger and palm is very much familiar with the average sizes of hands to the statistics;the other is fingers can not only realize flex function,but also move from the left to the right.Due to problems that much larger sizes of the bionic hand and lower performance than actual human hand,based on ergonomics,this paper presents the structural sizes and motion parameters by using the combining method of actual measuring and theoretical analysis ways,and designs the thumb,forefinger,middle finger,ring finger and little finger which can realize the flexing and left-right moving.Fingers's 3D model and assembly are completed by Pro/E,and some simulations such as natural state,stretching, false grip and cross grip,are made.Secondly,kinematics analysis of the virtual hand is made,and the foreward and inverse kinematics models are also accomplished by using D-H matrix transformation method.The test results of models indicates:models of the thumb and forefinger which is on behalf of other three fingers,are correct.Finally,the virtual dextrous hand's trajectory space is simulated.The simulation results show that the kinematics model is right,the trajectory space of the dextrous hand is very much familiar with the actual hand,and it can complete some common actions people used to do,such as cross grip,false grip, lateral pinching,are pinching,drawing and so on.In a word,it has good athletic performance.Main researching contents include:simulations on the trajectory space under natural state,left 15°,and right 15°of forefinger's gesture with,and natural state of the middle finger,ring finger and little finger,cross grip and false grip of the thumb,cross grip and false grip of all five fingers,and alse under cross grip and false grip the trajectory space relationship between thump and forefinger is alse simulated.