Miniaturized force/torque sensor for in vivo measurements of tissue characteristics

Annu Int Conf IEEE Eng Med Biol Soc. 2016 Aug:2016:2022-2025. doi: 10.1109/EMBC.2016.7591123.

Abstract

This paper presents the development of a surgical instrument to measure interaction forces/torques with organic tissue during operation. The focus is on the design progress of the sensor element, consisting of a spoke wheel deformation element with a diameter of 12 mm and eight inhomogeneous doped piezoresistive silicon strain gauges on an integrated full-bridge assembly with an edge length of 500 μm. The silicon chips are contacted to flex-circuits via flip chip and bonded on the substrate with a single component adhesive. A signal processing board with an 18 bit serial A/D converter is integrated into the sensor. The design concept of the handheld surgical sensor device consists of an instrument coupling, the six-axis sensor, a wireless communication interface and battery. The nominal force of the sensing element is 10 N and the nominal torque is 1 N-m in all spatial directions. A first characterization of the force sensor results in a maximal systematic error of 4.92 % and random error of 1.13 %.

MeSH terms

  • Intraoperative Complications / prevention & control
  • Signal Processing, Computer-Assisted
  • Silicon
  • Surgical Instruments*
  • Surgical Procedures, Operative*
  • Torque

Substances

  • Silicon