Design And Analysis Of The Reconfigurable Parallel Mechanism Based On The Unit Mechanisms

To meet the requirements of reconfigurability,adaptability for mechanisms used in modern production,in this paper,a novel way to design reconfigurable parallel mechanisms is proposed,which is by using the unit mechanism.Based on this method,some typical reconfigurable parallel mechanisms are designed and analyzed.Finally,a control system is designed to track the trajectory of the end-effector.This paper presented the unit mechanisms.The planar four-link mechanism is regarded as a unit,and a series of planar reconfigurable platforms is designed.At the same time,based on screw theory,regarded the spatial single-loop overconstrained mechanisms as the units,a class of spatial multi-loop reconfigurable platforms is designed.By combining reconfigurable platforms and parallel mechanisms,the reconfigurable parallel mechanisms have been obtained.According to the planar primary reconfigurable platform,a reconfigurable parallel mechanism is presented.Then,both the kinematic and performance are analyzed,so the reconfigurability is verified.For this mechanism,a performance index is proposed to optimize this mechanism.According to the planar secondary reconfigurable platform,a reconfigurable parallel mechanism is presented.Then,the kinematic,dynamic and performance are analyzed,so the reconfigurability is verified.For this mechanism,a PID control system is proposed to track the trajectory of the end-effector.According to the C1 reconfigurable platform,a reconfigurable parallel mechanism is presented.Then,the kinematic,dynamic and performance are analyzed,so the reconfigurability is verified.For this mechanism,a novel dynamic index is proposed.Based on this index,multi-objective optimization is processed.According to the F1C2 reconfigurable platform,a reconfigurable parallel mechanism is presented.Then,the kinematic,dynamic and performance are analyzed,so the reconfigurability is verified.In order to obtain special configuration to meet different task,BP neural network is trained.Based on this neural network,the relationship between performance indices and reconfigurable parameter is established.Regarded the C1 reconfigurable parallel mechanism as an example,the control system is established.In this control system,for each link,the adaptive sliding mode controller is applied.For the whole mechanism,the fuzzy PID controller is used to track the trajectory of the end-effector.