Nowadays most amputees express their disappointment for: 1) the large cost of buying and maintaining a prosthesis, 2) the increased weight of the device and 3) the difficulties they face with repairs [1]. Moreover the fear of damaging the prosthesis leads most of them to avoid using them in everyday life tasks and use instead simple hooks or grippers. On the other hand when the amputees are involved in the selection / preparation of the prosthesis (e.g., replication of an open-source design), the likelihood of prosthesis acceptance is increased. These findings confirm that amputees will certainly benefit from open-source, affordable, personalized, and light-weight prostheses, which can be easily developed and repaired.

The OpenBionics ^1 initiative [2], prepares and freely distributes open-source designs for the development of anthropomorphic, under-actuated, adaptive robot and prosthetic hands of low complexity and cost [3]. The proposed hands utilize novel differential mechanisms (e.g., a variation of the whiffletree or "seesaw mechanism") that block the motion of the individual fingers, allowing the user to select between 144 grasping postures and gestures using only 1 motor. Human-likeness of both robot structure and motion is achieved by employing in the design process, an index of anthropomorphism that utilizes parametric models derived from hand anthropometry studies [4]. The proposed hands can be easily reproduced with off-the-shelf materials and can be fabricated with rapid prototyping techniques (e.g., 3D printers).

References

[1] D. Edeer and C. W. Martin, "Upper limb prostheses - a review of the literature with a focus on myoelectric hands," 2013. [Online]. Available: www.worksafebc.com/evidence.

[2] Minas V. Liarokapis, Agisilaos G. Zisimatos, Christoforos I. Mavrogiannis and Kostas J. Kyriakopoulos, “OpenBionics: An Open-Source Initiative for the Creation of Affordable, Modular, Light-Weight, Underactuated Robot Hands and Prosthetic Devices”, 2nd ASU Rehabilitation Robotics Workshop, Arizona State University (ASU), Tempe, AZ (USA), 2014.

[3] George P. Kontoudis, Minas V. Liarokapis, Agisilaos G. Zisimatos, Christoforos I. Mavrogiannis and Kostas J. Kyriakopoulos, “Open-Source, Anthropomorphic, Underactuated Robot Hands with a Selectively Lockable Differential Mechanism: Towards Affordable Prostheses”, IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Hamburg (Germany), 2015.

[4] M. V. Liarokapis, P. K. Artemiadis, and K. J. Kyriakopoulos, "Quantifying anthropomorphism of robot hands," in IEEE International Conference on Robotics and Automation (ICRA). IEEE, 2013, pp. 2041–2046.

^1 The OpenBionics initiative (www.openbionics.org) was initiated via the support of the European Commission through the Integrated Project no. 248587, “THE Hand Embodied” (2010-2014), within the FP7-ICT-2009-4-2-1 program Cognitive Systems and Robotics and is inspired by the Yale Open Hand project (http://www.eng.yale.edu/grablab/openhand/). OpenBionics entered the Hackaday 2015 Prize competition with the following project: https://hackaday.io/project/4745-openbionics-affordable-prosthetic-hands.