Performance Assessment of a New Variable Stiffness Probing System for Micro-CMMs

Area of Science:

• Micro-scale metrology
• Mechanical engineering
• Sensor technology

Background:

• Designing micro-scale tactile probes requires balancing stiffness and flexibility.
• Probes need to be flexible to prevent damage but stiff enough to overcome surface forces.
• Existing probes face limitations in adapting to varying measurement demands.

Purpose of the Study:

• To develop a micro-scale tactile probe with actively controlled, variable stiffness.
• To address the design trade-off between probe flexibility and stiffness.
• To enhance precision and reliability in micro-scale tactile measurements.

Main Methods:

• Implementation of a novel active suspension structure within the micro-scale probe.
• Development of a control system to modulate and switch between two distinct probe stiffness values (stiff and flexible).
• Characterization of stylus tip displacement and measurement uncertainty during stiffness transitions.

Main Results:

• The active suspension system successfully modulated probe stiffness.
• A consistent flexible mode tip deflection within 12 nm (vertical axis) was achieved.
• The system demonstrated an overall uncertainty of 58 nm for 3D displacement measurements.

Conclusions:

• The developed variable stiffness micro-scale probe system offers significant potential for advanced metrology.
• Active stiffness modulation overcomes traditional design limitations in micro-tactile sensing.
• This technology enables more sensitive and robust micro-scale measurements.