A Miniaturized Piezo Stack Impact Actuation Mechanism for Out-of-Plane Freely Moveable Masses

Area of Science:

• Micro-actuation systems
• Mechanical engineering
• Physics of impact dynamics

Background:

• Traditional micro-actuation often relies on cantilevers, limiting displacement and speed.
• Achieving fast out-of-plane motion for accelerating objects against gravity requires specialized mechanisms.

Purpose of the Study:

• To develop and model a miniaturized impact actuation mechanism for accelerating objects against gravity.
• To enable large, cantilever-free displacements using a piezoelectric actuator.
• To analyze the influence of object properties on actuation performance.

Main Methods:

• Prototype development of a miniaturized impact actuator utilizing a piezoelectric stack actuator.
• Implementation of a high-current pulse generator for rapid actuator response.
• Modeling the mechanism using a spring-mass model for analytical comparison.
• Experimental testing with spheres of varying mass, diameter, and material composition.

Main Results:

• The piezoelectric impact actuator successfully provides fast out-of-plane displacement.
• A spring-mass model effectively describes the mechanism's behavior.
• Harder sphere materials resulted in significantly greater flight heights.
• Approximately 3 mm displacement was achieved for a 3 mm steel sphere using a compact piezo stack.

Conclusions:

• The miniaturized impact actuation mechanism offers a viable solution for accelerating objects against gravity.
• The design enables large displacements without the need for traditional cantilever structures.
• Object material properties critically influence the achievable displacement, with harder spheres yielding superior performance.