Performance Analysis On A New Six-dof Three Chains Parallel Mechanism

Since the Parallel mechanism advent, it have a rapid development in internationalacademic and engineering applications, the Stewart platform and it’s genenrativemechanism as a typical representative of the six-DOF&six-chains PM have the mostwidely used, but some disadventages limit its application in more fields, for exmple,six-DOF&six-chains PM’s work space is smaller and translational rotational coupling,poor workspace boundary controllability are insufficient.This paper based on the3-RRR spherical parallel mechanism and the characteristicsof the3-UPS PM, puts forward a new kind of six-DOF&three-chains which can realizedecoupling of translational and rotational part series compound, and the new institutionhas a larger work space, better kinematics and mechanics performance.Mainly it introduces the configuration, and obtains the positive solution analyticalexpressions. At the same it gives the agency hooke joint, the bar length and the rotationvice constraints. At first using the analytic geometry method obtains the positionworkspace with the change of parametric variation, and then using the three dimensionalspherical coordinates mapped boundary workspace and some of it’s section makesseveral groups of institutions in different position of attitude workspace. It analyzes thedifferences in position workspace posture change curve and provides the basis for theselection of structure parameters.Use function derivation method to solve out the agency’s velocity jacobian matrix,and produces more groups of dexterity in the work space distribution, and through thetheoretical mechanics release method establishes the organization of all components ofstatics balance equation, solving the equation and defines a static, torque transmissionperformance evaluation indicators and draws a set of evaluation index in the movementspace more different cross-section profile.Using the simulation software obtains the simulation model, then designing theactive platform’s trajectory obtaines the driving rod position, velocity and accelerationcurve, and further for dynamic analysis.