Design and kinematic optimization of a novel underactuated robotic hand exoskeleton


This study presents the design and the kinematic optimization of a novel, underactuated, linkage-based robotic hand exoskeleton to assist users performing grasping tasks. The device has been designed to apply only normal forces to the finger phalanges during flexion/extension of the fingers, while providing automatic adaptability for different finger sizes. Thus, the easiness of the attachment to the user’s fingers and better comfort have been ensured. The analyses of the device kinematic pose, statics and stability of grasp have been performed. These analyses have been used to optimize the link lengths of the mechanism, ensuring that a reasonable range of motion is satisfied while maximizing the force transmission on the finger joints. Finally, the usability of a prototype with multiple fingers has been tested during grasping tasks with different objects.

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This research was funded within the project “WEARHAP WEARable HAPtics for humans and robots” of the European Union Seventh Framework Programme FP7/2007-2013, Grant Agreement no. 601165 and project “CENTAURO - Robust Mobility and Dexterous Manipulation in Disaster Response by Fullbody Telepresence in a Centaur-like Robot” of the the European Union’s Horizon 2020 Programme, Grant Agreement no. 644839.

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Correspondence to Antonio Frisoli.

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Sarac, M., Solazzi, M., Sotgiu, E. et al. Design and kinematic optimization of a novel underactuated robotic hand exoskeleton. Meccanica 52, 749–761 (2017).

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  • Hand exoskeletons
  • Underactuated mechanism
  • Grasping
  • Kinematics optimization