Kinematics modeling of a 6-PSS parallel mechanism with wide-range flexure hinges

A novel 6-PSS flexible parallel mechanism was presented, which employed wide-range flexure hinges as passive joints. The proposed mechanism features micron level positioning accuracy over cubic centimeter scale workspace. A three-layer back-propagation (BP) neural network was utilized to the kinematics analysis, in which learning samples containing 1 280 groups of data based on stiffness-matrix method were used to train the BP model. The kinematics performance was accurately calculated by using the constructed BP model with 19 hidden nodes. Compared with the stiffness model, the simulation and numerical results validate that BP model can achieve millisecond level computation time and micron level calculation accuracy. The concept and approach outlined can be extended to a variety of applications.