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Updated: Jul 5, 2026

A Flexible Wearable Supernumerary Robotic Limb for Chronic Stroke Patients
Published on: October 27, 2023
Development of a one-handed nail clipper for stroke survivors
Christopher Carhart1, Rafal Ciechowski, Doug Groat
1Engineering Design and Communication, Section 17, Team 2, Segal Design Institute, The McCormick School of Engineering at Northwestern University, Evanston, Illinois, USA.
Abstract:
Due to the physical effects of stroke, many stroke survivors experience difficulty clipping their nails. Much of this difficulty is due to weakness in the upper extremities, loss of dexterity, spasticity, and vision problems. Our goal was to design a device that would help stroke survivors shorten their finger nails, providing increased independence, convenience, comfort, and safety compared to their current method of cutting nails. From user interviews and observations, we developed several prototypes to solve this problem. The final design, the Step 'n Snip, consists of a finger nail clipper mounted on an inclined, rotatable metal rod. The clipper is attached to a foot pedal with a long steel bike brake cable, which the pedal then uses to actuate the clipper. The pedal is mounted on a base that is shaped such that it provides a nesting space for the clipper frame during storage; the two parts are kept together by a swiveling clip. The clipper itself is at a convenient height for users and is fitted with a nail clippings collection system.

