Biomedical engineering students create low-cost robotic arm as an alternative to conventional prostheses

ARM2u is a multidisciplinary biomedical engineering team made up of 15 students on the bachelor’s degree in Industrial Technology Engineering, the master’s degree in Industrial Engineering and the master’s degree in Automatic Control and Robotics at the Barcelona School of Industrial Engineering (ETSEIB) of the Universitat Politècnica de Catalunya - BarcelonaTech (UPC).

Since 2018, this group of young students has been working on the development of a customizable arm prosthesis that responds to the user’s nerve impulses. It is a transradial prosthesis—which replaces an arm missing below the elbow—with myoelectric control, i.e. controlled by the natural electrical signals produced by muscle contraction.

The prosthesis is a fully functional robotic arm that enables hand pronosupination (forearm rotation) and opening/closing movements. It is based on EMG sensors, which collect the commands from the patient’s muscle contraction and transform these electrical impulses into a signal that the microcontroller can understand and use.

The design of the prosthesis allows for adjustment to the user’s arm size and has a reduced weight, which makes it more comfortable.

Improved prosthesis with AI and a hand with fingers

After having created two prototypes, the team continues to work to improve the prosthesis. They have developed myoelectric control technology based on pattern recognition using AI techniques, which allows the prosthesis to be even more adaptable. They are also working on developing a hand with fingers and incorporating it into the next version of the prototype.

With this robotic arm, the team will compete in the Cybathlon 2024, the main event of the Cybathlon Challenge, which will take place in October 2024. ARM2u will be the only Spanish team participating. In this competition, people with physical disabilities—the “carriers”—test prostheses, developed by research teams from universities and companies around the world, by tackling everyday tasks, such as such handling and transporting objects and placing them in a specific position inside cubes with different slots. The team’s participation in the latest edition of the championship, the Cybathlon 2023, in 29 March has allowed them to demonstrate the advances in the prosthesis’ technology compared to the previous version and also to spark the interest of the audience and participating companies.

Low-cost, easy-to-produce prosthesis

The aim of the ARM2u team is to start marketing a prosthesis that helps people with this disability at a much lower cost than that of similar existing models. This prototype is easy to produce at a low cost, since it is made of PLA plastic using 3D printing techniques.

Searching for sponsors and new carriers

The team is looking for sponsors to help take the project forward and market the prosthesis. As explained by team leader álvaro García Martín, "sponsor support is key to reaching our goals. Small development teams like ARM2u need resources and industry knowledge from different sponsors to improve the technology incorporated into the prosthesis, its functions and the adaptability for end users."

The team is also looking for new carriers. The carrier is a key actor in the design and development of prostheses, being the person for whom the prototype is customized and who tests its functions in a real environment.