The Singularity Analysis And Position Limitation Design Of 6-DOF Controller Based On Parallel Mechanism With Sub Closed-chains

Six-dimensional controller can simultaneously perform spatial translation and rotation operations with 6-DOF output talent.It has great application prospects in health care,industrial production,entertainment and other fields.A novel controller is proposed in this paper.Its main body is the 3-5RUU parallel mechanism,which,compared with that of existing six-dimensional controllers,has fewer branches and contains sub-closed loops.Therefore,it has ideal workspace and high dexterity and thus significantly better performance.In order to ensure that the controller can avoid singularity loci,this paper studies the kinematics and singularity loci of the mechanism,and then designs its mechanical position limitation.The main work of this paper is as follows:Firstly,closed vector method is used to establish the inverse kinematic model on the basis of the characteristics of 3-5RUU parallel mechanism;then numerical iteration method is applied on the basis of the inverse kinematic model to build its forward kinematic model.These two models are verified by ADAMS simulation software.Based on the inverse model,the first derivative of the time is obtained,and the Jacobian matrix of the inverse model of the mechanism is obtained by using the derivative of multivariate function and matrix multiplication.The working achievement is the foundation of mathematics of solving singularity loci.Secondly,the Jacobian matrix is analyzed in case of a singular matrix to solve two boundary singularity loci of the controller.Considering the defect of Jacobian matrix in solving singularity loci,kinematics analysis of special configuration is analyzed to solve the special singularity loci.The singularity loci solved here is the foundation of mechanical position limitation.Finally,considering the three singularity loci solved and the practical working conditions of the six-dimensional controller,the mechanical position limitation of the six-dimensional controller is carried out,and a related scheme is put forward to avoid the controller from singularity loci during operation.In this paper,the kinematics and singularity of the controller are analyzed,and the mechanical position limitation is carried out,which ensure that the controller can realize its capabilities and provide a guarantee for its further application in the future.