Optimal design of a planar parallel 3-DOF nanopositioner with multi-objective

- A general modeling and optimization approach of selecting 16 key parameters of a planar parallel 3-DOF nanopositioner .
- Seven performance indexes and four constraints are involved in modelling the nanopositioner.
- All the modified-Pareto-optimality solutions are obtained using a multi-objective particle swarm optimization (MOPSO) algorithm.
- Several optimization cases are conducted to show the high efficiency
- Simulation and experimental results of two design examples validate the proposed modelling and optimization method.

Planar parallel three-degrees-of-freedom (3-DOF) nanopositioners have been used for sample scanner in scanning probe microscopy (SPM), wafer positioner in nanoimprint lithography, micro/nano manipulation, and precision machining. The performance evaluation indexes involve workspace, natural frequency, input coupling ratio, precision/accuracy, speed, payload capability, and output compliance. The tradeoff of multiple indexes is an important factor needing to be considered in the process of designing a nanopositioner. Stress, input stiffness, fatigue reliability, and force transmission are also the main constraints. This paper describes an optimal approach of selecting 16 key parameters of a planar parallel 3-DOF nanopositioner. Seven performance indexes and four constraints are involved in modelling the nanopositioner. A general analysis, optimization, and decision-making method is presented. All the modified-Pareto-optimality solutions are obtained using a multi-objective particle swarm optimization (MOPSO) algorithm. Different applications select preferred Pareto solutions from the same Pareto front. Several optimization cases are given to show the high efficiency of the proposed modelling and optimization method. Two design examples are given based on the corresponding demand of two typical application cases, respectively. The simulation and experimental results validate the proposed modelling and optimization method. The research results of this paper are helpful to design a planar parallel 3-DOF nanopositioner for different applications.