Modelling of a Soft Sensor for Exteroception and Proprioception in a Pneumatically Actuated Soft Robot

Soft sensors are crucial to enable feedback in soft robots. Soft capacitive sensing is a reliable technology that can be embedded into soft pneumatic robots for obtaining proprioceptive and exteroceptive feedback. In this paper, we model a soft capacitive sensor that measures both the actuated state as well as applied external forces. We develop a Finite Element Model using a multiphysics software (COMSOL®). Using this model, we investigate the change in capacitance with the application of external force, for a range of different internal pressures and strains. We hope this study is helpful in understanding the coupling of internal inputs and external stimuli on the feedback obtained from the sensors and help us design better sensory systems for soft robots.

[1]  TotaroMassimo,et al.  Integrated Simultaneous Detection of Tactile and Bending Cues for Soft Robotics. , 2017 .

[2]  Sung Youb Kim,et al.  Giant tunneling piezoresistance of composite elastomers with interlocked microdome arrays for ultrasensitive and multimodal electronic skins. , 2014, ACS nano.

[3]  Veikko Sariola,et al.  Screen-Printed Curvature Sensors for Soft Robots , 2018, IEEE Sensors Journal.

[4]  Jennifer C. Case,et al.  Multi-mode strain and curvature sensors for soft robotic applications , 2017 .

[5]  J. Albert,et al.  Tilted fiber Bragg grating sensors , 2013 .

[6]  Jennifer C. Case,et al.  Multi-Element Strain Gauge Modules for Soft Sensory Skins , 2016, IEEE Sensors Journal.

[7]  Kevin O'Brien,et al.  Optoelectronically innervated soft prosthetic hand via stretchable optical waveguides , 2016, Science Robotics.

[8]  Cagdas D. Onal,et al.  A precise embedded curvature sensor module for soft-bodied robots , 2015 .

[9]  Massimo Totaro,et al.  Revealing bending and force in a soft body through a plant root inspired approach , 2015, Scientific Reports.

[10]  Sanlin S. Robinson,et al.  Highly stretchable electroluminescent skin for optical signaling and tactile sensing , 2016, Science.

[11]  Dario Floreano,et al.  Ultrastretchable Strain Sensors Using Carbon Black‐Filled Elastomer Composites and Comparison of Capacitive Versus Resistive Sensors , 2018 .

[12]  CianchettiMatteo,et al.  Soft Robotics Technologies to Address Shortcomings in Today's Minimally Invasive Surgery: The STIFF-FLOP Approach , 2014 .

[13]  Kaspar Althoefer,et al.  Embedded electro-conductive yarn for shape sensing of soft robotic manipulators , 2015, 2015 37th Annual International Conference of the IEEE Engineering in Medicine and Biology Society (EMBC).

[14]  Kaspar Althoefer,et al.  Tendon-Based Stiffening for a Pneumatically Actuated Soft Manipulator , 2016, IEEE Robotics and Automation Letters.

[15]  Nahal Aliheidari,et al.  3D printed highly elastic strain sensors of multiwalled carbon nanotube/thermoplastic polyurethane nanocomposites , 2017 .

[16]  Jian Zhu,et al.  A Soft Jellyfish Robot Driven by a Dielectric Elastomer Actuator , 2016, IEEE Robotics and Automation Letters.

[17]  Cagdas D. Onal,et al.  A composite soft bending actuation module with integrated curvature sensing , 2016, 2016 IEEE International Conference on Robotics and Automation (ICRA).

[18]  LuoMing,et al.  Toward Modular Soft Robotics: Proprioceptive Curvature Sensing and Sliding-Mode Control of Soft Bidirectional Bending Modules. , 2017 .

[19]  Kaspar Althoefer,et al.  A Novel Concept for Safe, Stiffness-Controllable Robot Links. , 2017, Soft robotics.

[20]  Youngjin Jeong,et al.  Highly Sensitive and Multimodal All‐Carbon Skin Sensors Capable of Simultaneously Detecting Tactile and Biological Stimuli , 2015, Advanced materials.

[21]  Xinran Wang,et al.  A Self‐Healable, Highly Stretchable, and Solution Processable Conductive Polymer Composite for Ultrasensitive Strain and Pressure Sensing , 2018 .

[22]  Kean C. Aw,et al.  Highly stretchable printed strain sensors using multi-walled carbon nanotube/silicone rubber composites , 2017 .

[23]  Kaspar Althoefer,et al.  An optical curvature sensor for flexible manipulators , 2013, 2013 IEEE International Conference on Robotics and Automation.

[24]  Kaspar Althoefer,et al.  Macrobend optical sensing for pose measurement in soft robot arms , 2015 .

[25]  P. Bifulco,et al.  A stretchable, conductive rubber sensor to detect muscle contraction for prosthetic hand control , 2017, 2017 E-Health and Bioengineering Conference (EHB).