Conference Paper

A multi-axis MEMS force-torque sensor for measuring the load on a microrobot actuated by magnetic fields

ETH Zurich, Zurich
DOI: 10.1109/IROS.2007.4399004 Conference: 2007 IEEE/RSJ International Conference on Intelligent Robots and Systems, October 29 - November 2, 2007, Sheraton Hotel and Marina, San Diego, California, USA
Source: DBLP


This paper presents the design of a multi-axis micro force-torque sensor. The sensor is able to measure forces along two axes and a torque perpendicular to these forces. The load is measured by capacitive comb drives which provide a high sensitivity. The microfabrication process, the sensor readout electronics as well as the calibration procedure are presented. The sensor was used to measure the force and torque on a magnetically actuated microrobot. This microrobot is assembled from microfabricated nickel parts for directed drug delivery inside the human body. Precise knowledge load on the microrobot is required for accurate positioning and control of the robot. The three-axis micro sensor is used to simultaneously measure the forces and torques acting on the microrobot in a magnetic field and thus provides valuable data for magnetic control methods of microrobots.

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Available from: Zoltán Nagy,
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    • "A piezoresistive torque sensor has been presented in [27]. In addition, a three-axis capacitive MEMS force-torque sensor has been reported in [28] and this sensor is able to measure forces along two axes and a torque perpendicular to these forces. As we know, forces can be sensed in a plane, while a torque perpendicular to this plane can be measured. "
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    • "Indeed the possibility to assemble complex and varied microsystems is in current investigation and already shows promising results [2], [3], [4]. Micro-assembly constitutes new challenges according to size and specificities of micro-parts in reference to [5], [6], [7] and adapted tools are under development (visual servoing [8], force measurement [9], control strategies [10], 1 hal-00417663, version 1 -16 Sep 2009 Author manuscript, published in "Micro & Nano Letters 4, 3 (2009) 148-154" DOI : 10.1049/mnl.2009.0034 microrobots [11] etc.). "
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