Mechanics Testing System For The Joints Of Extravehicular Spacesuit Gloves Based On A Humanoid Dexterous Hand

In order to ensure the safety and efficiency of astronauts’ extravehicular activity(EVA),EVA spacesuit gloves need to be tested for joint mechanical properties during the development process.The best method currently considered is to put a humanoid dexterous hand with sensory ability inside the glove.However,the traditional humanoid dexterous hand is difficult to enter the narrow multi-cavity space of the EVA spacesuit glove due to its large size and inconvenient disassembly,let alone the evaluation of the mechanical properties.In this paper,a set of mechanics testing system for the joints of EVA spacesuit gloves based on humanoid dexterous hand is designed,and the joint mechanics performance test is completed inside the gloves.In response to the task requirements of the mechanics test of the EVA spacesuit glove,a humanoid dexterous hand including five modular fingers and a parallel wrist driven by linear motors is proposed.Each part of the dexterous hand could be delivered into the glove separately and then assembled inside,which breaking through the space limitation.The auxiliary tooling required for the mechanical test of the glove joint and the finger and wrist calibration mechanism to compensate for the measurement error are designed.A mathematic model of the humanoid dexterous hand is formulated by using the geometric constraints and principle of virtual work to analyze the kinematics and statics of the dexterous hand.The bending angle and load force/torque of the finger and wrist are estimated by the displacement and driving force of the driving motor.Aiming at the finger mechanism of the humanoid dexterous hand,taking high anthropomorphism and maximizing the driving force as the optimization objective,the particle swarm algorithm with constraints is used to optimize the parameters of the finger phalanx.The correctness of the kinematics and statics model and the effectiveness of parameter optimization are verified on the simulation platform.The correctness of the kinematics and statics model and the effectiveness of parameter optimization are verified on the simulation platform.Based on the designed glove mechanics test system,the glove outer calibration experiment and glove inner joint mechanics test experiment are designed,and the calibration experiment data is compared with the theoretical model to verify the correctness of the model.The humanoid dexterous hand is put into the glove for testing,and the relationship curve between the bending angle and the load force/torque of the end of the finger and the wrist is obtained in a motion cycle,which realizes the evaluation of the mechanical performance of the glove joint.