050026: A Force Sensing Probe for Micromanipulation and Microassembly

A current limitation with existing micro-probe tips is their relatively high degree of bending when encountering objects on surfaces. This significantly limits the ability of micro-probes to manipulate micro-objects. In addition, the sensor can only have a small dynamic range in its bending if it is to maintain high accuracy in manipulating objects.


The invention overcomes the bending limitations of existing micro-probe tips through a highly sensitive PVDF (polyvinylidene fluoride) piezoelectric force sensor to measure contact force and its rate of change. An active micro-force sensor is developed using a cantilevered beam structure with PVDF layers bonded to its entire surface. An accurate force reading can be attained through feeding back the piezoelectric voltage to the sensor, causing the PVDF layer to straighten the beam by applying an opposite deformational force. Because the sensor remains relatively undeformed, this strategy greatly enlarges the dynamic range of the sensor, and enhances its ability to manipulate objects during microasembly, by making the sensor act as a tool.


  • Potential use in future manufacturing of micro devices: By improving force sensing accuracy and the ability to manipulate micro-objects, this invention may provide a critical step towards the development of automated manufacturing processes for batch assembly of micro devices.
  • Improvements in probe manipulation: The probe tip does not bend making the sensor a more capable tool.


Micro-scale devices serving as tools for manipulating and assembling very small objects.

IP Protection Status

US 7367242 (issued May 6, 2008)
Patent Information:


For Information, Contact:

Raymond Devito
Technology Manager
Michigan State University - Test
Ning Xi
Yantao Shen