Towards an Affordable Assistive Device for Personal Autonomy Recovery in Tasks Required of Manual Dexterity

This paper reviews the results of a challenging engineering project that arose with the goal of implementing an electromechanical, automatic, portable, and inexpensive device. The device should be able to assist people who lack of dexterity in their hands to use small tools and everyday utensils, such as scissors or tweezers. In this paper, the hardware development and software functionality are described. The original specifications were developed to implement an affordable functional prototype able to serve as a low-cost assistive technology. Several commonly used electronic devices were integrated to create an innovative application. A simple mechanical system based on gears and a worm screw is used to convert the stepper motor rotation to a linear movement on the device tip. A tool-oriented control to increase the device usability was designed through two simultaneous communication channels: touch-screen and smartphone app. Pilot trials were conducted at healthcare facilities to evaluate the technical feasibility, the obtained functionality, as well as the device acceptance by target users. Based on user experience design, the app functionality was enhanced and subsequently tested. Finally, a review and reformulation of the specifications of the original design were accomplished. These changes helped to achieve a system with a lower manufacturing cost and better acceptance, while considering the user in the development cycle.