A Friction-Inertial-Based Rotary Motor: Design, Modelling and Experiments

Area of Science:

• Mechanical Engineering
• Materials Science
• Robotics

Background:

• Friction-inertial rotary motors offer high resolution and large load capacity.
• Shear piezoelectric actuators (SPAs) are key components in advanced motor designs.
• Step loss and limited step size under external load are challenges in SPA-driven motors.

Purpose of the Study:

• To propose a friction-inertial rotary motor driven by shear piezoelectric actuators (SPAs).
• To enhance motor performance by eliminating step loss and increasing step size using a power-function-shape driving signal.
• To investigate the influence of driving signal characteristics and preload on motor motion modes.

Main Methods:

• Numerical simulation of motor dynamics.
• Experimental validation of simulated results.
• Analysis of two distinct motion modes: stick-shoot and stick-slip-shoot.

Main Results:

• The power-function-shape driving signal effectively increases step size and reduces step loss.
• Two motion modes, stick-shoot and stick-slip-shoot, were identified and characterized.
• Motor performance is significantly influenced by preload and driving signal base number, not SPA size.

Conclusions:

• The proposed SPA-driven rotary motor achieves superior performance, including high resolution and large load capacity.
• The stick-shoot motion mode enables larger step sizes compared to stick-slip-shoot.
• Optimizing preload and driving signal parameters allows for further motor downsizing and performance tuning.