Research On Redundantly Driven Six-DOF Heavy-duty Parallel Swinging Table

After developing products for heavy-duty vehicles,it is necessary to test and track the electronic equipment on the vehicle in various road conditions so that the performance of the vehicle can meet the standards.In order to reduce the design cycle and experimental costs of the vehicle,this paper studies the motion simulation swing table for heavy vehicles.The simulation swing table can simulate the movement of the vehicle on land,including three-dimensional movement,three-dimensional rotation and compound movement.The main research content of this article is as follows:First,according to the laws of the movement of the vehicle on the land,a design index for a motion simulation swing table was developed.Aiming at the fact that the existing parallel mechanism is difficult to realize heavy load and provide a large bearing surface,a redundantly driven six-degree-of-freedom heavy-duty parallel swinging table is proposed.A variety of redundantly-driven parallel rocking tables are integrated,including6-UPS/6-PUS parallel configurations and 6-UPS/3-PUS parallel configurations.The6-UPS/3-PUS parallel configuration was chosen as the subject of this study.Secondly,the kinematics and dynamics of redundantly driven parallel-connected rocking tables are analyzed.The inverse solution of the position of the parallel swing table is solved by the coordinate transformation and geometric constraint,and the position solution of the mechanism is solved by the quasi-Newton method.Through the first-order and second-order influence coefficients,the mapping relationship between the speed and acceleration of the parallel mechanism and the active driving branch and the redundant driving branch is obtained.Newton-Euler equation is used to derive the Hessian matrix to establish the mapping relationship between the driving force of the active driving branch of the parallel mechanism and the bearing platform and the load weight.Again,the drive system of a redundantly driven parallel swing table was designed.According to the kinematics and dynamics motion parameters,the hydraulic servo system was selected as its drive system.In order to meet the system reliability and system accuracy,constant pressure hydraulic source control system of unloading type is adopted,constant pressure is adopted,and multi-pump confluent oil supply mode is used to provide large flow and high pressure system to calculate hydraulic component parameters in AMESim simulation software.The system was modeled and the hydraulic components were parameterized.Finally,a system designed to redundantly drive a parallel swing table was designed.The parallel swing table system includes a mechanical system,a hydraulic servo system,an electrical control system,a computer control system,and an auxiliary equipment system.The working process of the parallel swing table is introduced.The mechanical system of the parallel swinging table was designed and optimized.Finally,the PID controller is designed and the SimMechanics module is used to simulate and analyze the mechanical system of the parallel swinging platform,which verifies the feasibility of the PID controller.