Super-elastic ultrasoft natural rubber-based piezoresistive sensors for active sensing interface embedded on soft robotic actuator

verfasst von

Shib Shankar Banerjee, Injamamul Arief, Rebecca Berthold, Mats Wiese, Max Bartholdt, Debashis Ganguli, Siddhartha Mitra, Subhradeep Mandal, Jörg Wallaschek, Annika Raatz, Gert Heinrich, Amit Das

Abstract

Piezoresistive soft composites are ubiquitous in strain sensing that manifests in a dramatic increment of electrical resistivity upon elongation. A piezoresistive strain sensor embedded-soft robotic arm has been a challenging task in terms of surface compatibility, shape and dynamics of the soft robotic components. We present a super-elastic, ultrasoft natural rubber composite containing multiwalled carbon nanotubes in presence of a hydrofinished oil-based softener. The resulting conducting elastomer offered a line-up of compelling characteristics such as low electrical percolation (<2 vol%), ultra-softness (Shore A harness ∼19), elastic modulus in the kPa range (∼350 kPa at 100% elongation), ultra-stretchability (∼800%) and high tensile strength (∼10.5 MPa). In addition, the sensor exhibited low hysteresis (3.5%), high piezoresistive sensitivity (gage factor≈472) and switching response over wide strain range (70%) and stable sensing performance for multiple test cycles (>1000). On account of the excellent responses mentioned, the sensor could detect human motion and has also been demonstrated in this paper. Furthermore, the sensing strip embedded on a soft robotic pneumatic actuator mounted on a test rig showed excellent movement detection response upon actuation. This proof-of-concept sensor-integrated soft robotic interface could be instrumental in the future development of proprioceptive sensing robots and soft robotic segments.

Organisationseinheit(en)

Institut für Dynamik und Schwingungen
Institut für Montagetechnik und Industrierobotik
Institut für Mechatronische Systeme

Externe Organisation(en)

Leibniz-Institut für Polymerforschung Dresden e.V.
Indian Institute of Technology Delhi (IITD)
Bharat Petroleum Corporation
Technische Universität Dresden

Typ

Artikel

Journal

Applied Materials Today

Band

25

Publikationsdatum

12.2021

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Allgemeine Materialwissenschaften

Elektronische Version(en)

https://doi.org/10.1016/j.apmt.2021.101219 (Zugang: Geschlossen)