Investigation Of Dynamic Similitude Characteristics Of Ground Test Model Of Space Manipulator

As the space station construction and the deepening of outer space exploration,space manipulator has been more and more widely used in the field of aerospace.Because it is difficult to realize on-orbit repair,space manipulator must go through strict ground test before launching into target location.Research of dynamic similitude characteristics in allusion to the two characteristics of space manipulator:One is the large-scale structure of mechanical arm,bring inconvenience to ground test,and the manufacturing cost is high;the other is the microgravity or low-gravity environment.Many scholars both at home and abroad often do experiment by simulating the working environment of space manipulator.It is caused some problems,such as high cost and big risk.Considering the two problems,this article launches the research.By changing the material,structure size of model,it can save the cost and simplify the operation.Also,it can improve the control precision of prototype robot by adjusting the control parameters based on model test.So the investigation of dynamic similitude characteristics of ground test model of space manipulator has great significance.First of all based on the simplify structure of space manipulator,kinetic equations are derived.With equation analysis and dimensional analysis,the similarity relation of space manipulator is derived.Then,considering flexibility of link and the similarity relation of space manipulator is derived.A comparison analysis is made between rigid and flexible manipulator.Based on the identification of system parameter,the mothd on vibration suppression is studied.Furthermore,in allusion to the problem that flexible joints caused system stability reduce and difficulties in control,take single connecting-rod mechanical arm for example,dynamics model is established based on the simplification of flexible joint.And similitude design criterion of space manipulator's ground test model is derived.Research the influence of joint parameters on the mechanical arm dynamics.Determine the importance of the spring stiffness and damping coefficient,and determine the design process.Finally,through software simulation and experiment,verifies the correctness of similarity relation.