Chip-on-tip endoscope incorporating a soft robotic pneumatic bending microactuator


In the ever advancing field of minimally invasive surgery, flexible instruments with local degrees of freedom are needed to navigate through the intricate topologies of the human body. Although cable or concentric tube driven solutions have proven their merits in this field, they are inadequate for realizing small bending radii and suffer from friction, which is detrimental when automation is envisioned. Soft robotic actuators with locally actuated degrees of freedom are foreseen to fill in this void, where elastic inflatable actuators are very promising due to their S3-principle, being Small, Soft and Safe. This paper reports on the characterization of a chip-on-tip endoscope, consisting out of a soft robotic pneumatic bending microactuator equipped with a 1.1 × 1.1 mm2 CMOS camera. As such, the total diameter of the endoscope measures 1.66 mm. To show the feasibility of using this system in a surgical environment, a preliminary test on an eye mock-up is conducted.

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This research is supported by the Fund for Scientific Research-Flanders (FWO), and the European Research Council (ERC starting grant HIENA).

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Correspondence to Benjamin Gorissen.

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Gorissen, B., De Volder, M. & Reynaerts, D. Chip-on-tip endoscope incorporating a soft robotic pneumatic bending microactuator. Biomed Microdevices 20, 73 (2018).

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  • Minimally invasive surgery
  • Chip-on-tip endoscope
  • Bending actuator
  • Soft robotic actuator