Dynamics Modelling And Simulation For Closed Five-bow-shaped-bar Linkage With Redundant Actuation

Closed five-bow-shaped-bar linkage is a rolling mechanism driven by heavy torque,It is made up of five identical bow-bar modules from the head to the tail in series;When the rod touches the ground,the centroid of the virtual circle is paranoid with the virtual circle of the corresponding touchdown bar By changing their shape,and the gravity biased moment is generated to drive the mechanism to roll.There would be a peak load unceasingly during the rolling,if the rated power of the motor is increased simply,it could lead to a rise in system quality and energy consumption.The redundant driver can reduce the maximum instantaneous load of the branch by distributing the driving torque in a coordinated way,but it would affect the implementation of the function and even damage the equipment if it is Unsuitable to distribute the driving torque in coordinated distribution.For the Closed Five-bow-shaped-bar Linkage with Redundant Actuation,the dynamics study not only make the power and power distribution of the active joint more balanced,but also provide a theoretical basis for actuator selection and dynamic control.Therefore,it is necessary to study the redundant actuation of the mechanism.In the first of all,we study the dynamic rolling process of the closed five-bow-shaped-bar linkage,and establish Kinematic analysis model of the closed five-bow-shaped-bar linkage,the speed and acceleration of the driving link and the restrained link are analyzed respectively,the acceleration matrix and angular acceleration matrix of each member are obtained,and then the resultant force and torque of each member are obtained;Secondly,the Newton Euler dynamic equation of the mechanism is established,The expression of driving torque for the main driving joints and redundant actuated joints with unknown variables can be obtained by solving the equation.Thirdly,the pseudo inverse method is used to coordinate the driving torque,and the 2 norm of the instantaneous driving torque of the main driving joint and the redundant actuated joint is minimized.Finally,the joint trajectory of the dynamic rolling process of the mechanism is given,and the driving torque under the non redundant drive and the redundant drive mode is calculated respectively.The calculation results show that the redundancy drive mode can significantly reduce the maximum instantaneous driving torque,and the driving torque is more balanced.To provide theoretical support for actuator selection and dynamic precise control of the closed five-bow-shaped-bar linkage...