A Fabric-Based Approach for Softness Rendering

Part of the Springer Series on Touch and Haptic Systems book series (SSTHS)


In this chapter we describe a softness display based on the contact area spread rate (CASR) paradigm. This device uses a stretchable fabric as a substrate that can be touched by users, while contact area is directly measured via an optical system. By varying the stretching state of the fabric, different stiffness values can be conveyed to users. We describe a first technological implementation of the display and compare its performance in rendering various levels of stiffness with the one exhibited by a pneumatic CASR-based device. Psychophysical experiments are reported and discussed. Afterwards, we present a new technological implementation for the fabric-based display, with reduced dimensions and faster actuation, which enables rapid changes in the fabric stretching state. These changes are mandatory to properly track typical force/area curves of real materials. System performance in mimicking force-area curves obtained from real objects exhibits a high degree of reliability, also in eliciting overall discriminable levels of softness.


Contact Area Contact Force Haptic Device Linear Actuator Tactile Information 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.



This work is supported by the European Research Council under the ERC Advanced Grant \(n^\circ \) 291166 SoftHands (A Theory of Soft Synergies for a New Generation of Artificial Hands). The research leading to these results has also received funding from the European Union Seventh Framework Programme FP7/2007–2013 under grand agreement \(n^{\circ }\) 248587 THE (The Hand Embodied) and under grant agreement \(n^{\circ }\) 601165 WEARHAP (WEARable HAPtics for humans and robots).


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Copyright information

© Springer-Verlag London 2014

Authors and Affiliations

  1. 1.Department of Advanced Robotics (ADVR)Istituto Italiano di TecnologiaGenoaItaly
  2. 2.Research Centre “E. Piaggio”Università di PisaPisaItaly

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