Direct Kinetostatic Analysis of a Gripper with Curved Flexures

Area of Science:

• Mechanical Engineering
• Micro-electro-mechanical-systems (MEMS)
• Robotics

Background:

• Planar mechanisms in MEMS often utilize elastic curved beams as flexure hinges.
• Conventional models are insufficient for curved beams due to their complex behavior and multiple degrees of freedom.
• Sophisticated kinetostatic models are required for accurate prediction of curved beam performance.

Purpose of the Study:

• To develop a direct kinetostatic analysis method for planar grippers with elastic curved beams.
• To derive closed-form solutions for the tangent stiffness matrix of curved beam flexures.
• To enable accurate real-time modeling for microscale applications.

Main Methods:

• Formulation of direct kinetostatic analysis for planar grippers.
• Derivation of tangent stiffness matrices using two simplified models.
• Application of the Newton-Raphson iterative method to solve non-linear problems.
• Case study on a four-bar linkage gripper with elastic curved beam joints.

Main Results:

• A closed-form solution for the tangent stiffness matrix of elastic curved beams was successfully derived.
• The Newton-Raphson method effectively solved the non-linear kinetostatic problem.
• The proposed technique demonstrated its utility for real-time analysis.

Conclusions:

• The developed direct kinetostatic analysis is suitable for elastic curved beam flexures in MEMS.
• This method facilitates real-time grasping operations at the microscale.
• The study provides a valuable tool for designing and analyzing MEMS grippers.