Dynamic Characteristics Study On The Measuring Mechanical Arm Of The Spacesuit Operational Ability

Spacesuit for extravehicular activity (EVA) is the key equipment for astronaut to provide life support. As the astronaut needs to finish some kinds of extravehicular work, EVA spacesuit should also have a good mobility performance. This is an ergonomics problem. The measuring of operational limit region of EVA spacesuit is the main point in spacesuit ergonomics. Base on developed a measuring arm system for EVA spacesuit operational ability, this thesis studied the dynamics of the manipulator based on the robotics theory, and discussed the dynamics of the arms influencing the measurement of operational ability. This provides an important tool for the study of EVA spacesuit. The following work has been done in this thesis.Based on kinematics and dynamics theory, the describe method of a rigid body situation and posture, homogeneous transformation matrices model of the manipulator was established. The kinematics of the manipulator and it' inverse kinematics was discussed. The workspace of the manipulator was plotted by Monte Carlo method to verifying the manipulator measurement rang requirements. The kinematics model of the manipulator was also established by D-H coordinates method. The kinematics characteristics of the manipulator were simulated by both Matlab/Simulink and Robotics ToolBox. Also, the inverse kinematics of the manipulator was established and simulated by FM algorithm. These studies are the base for the dynamics modeling and simulation of the manipulator.Parameter of the manipulator, such as mass of bars, position of mass center and inertia of the bars are calculated, both forward and inverse dynamic equations of the manipulator was established by simultaneous constraint method, and the equations were solved by Matlab /Simulink. The dynamic characteristics were obtained. When a constant force was acted on the end of the handle of the manipulator, the angle displacement, angle velocity and angle acceleration of every joint were calculated by Matlab Programming and Simulink simulation. When the handle was moved in a certain pattern, force needed to act on it was calculated.A three-D model of the manipulator was established, and the dynamics characteristics was also simulated by software of Adams based on Lagrange theory. And the results are accordance with that simulated by Matlab.Based on the dynamics characteristics research, operation methods of the measuring manipulator was improved and tested. And an operation manual of the test method of the reachable region, operation region of the astronaut in spacesuit was improved. Furthermore, software of 2-d 3-d visualization of the test results of reachable region, operation region and viewable region were developed, these works consummated the measurement system.The dynamics characteristics research of the measuring manipulator improved the accuracy of the test system; also supply a good basis for developing constant resistance measuring robot for better measurement.