Position-Space-Based Design of a Symmetric Spatial Translational Compliant Mechanism for Micro-/Nano-Manipulation.

Area of Science:

• Mechanical Engineering
• Robotics
• Compliant Mechanisms Design

Background:

• Symmetric compliant mechanisms offer superior motion performance but often suffer from over-constraint issues, leading to complex structures and high actuation stiffness.
• Existing design methods for symmetric compliant mechanisms frequently result in over-constrained systems, limiting their practical application.

Purpose of the Study:

• To present a position-space-based design approach for creating symmetric compliant mechanisms with reduced over-constraint.
• To design and analyze a symmetric spatial translational compliant parallel mechanism (symmetric XYZ CPM) using the proposed method.

Main Methods:

• Reconfiguring non-symmetric compliant mechanisms into symmetric ones by rearranging compliant modules and introducing minimal over-constraints.
• Nonlinear analytical modeling of actuation forces for the symmetric XYZ CPM, validated against nonlinear finite element analysis (FEA).
• Fabrication of a physical prototype for experimental verification.

Main Results:

• The position-space approach successfully reconfigures non-symmetric mechanisms into symmetric ones with minimal over-constraints.
• Analytical models for actuation forces showed less than 2.58% difference compared to FEA results.
• Experimental testing and FEA simulations confirmed desirable motion characteristics, including minimized cross-axis coupling.

Conclusions:

• The position-space-based design approach is effective for developing simplified and high-performance symmetric compliant mechanisms.
• The designed symmetric XYZ CPM demonstrates excellent motion control and reduced parasitic motion.
• The findings pave the way for more efficient and practical applications of symmetric compliant mechanisms in various fields.