The idea of developing limb prostheses that can be connected to man by means of special neural interfaces dates back to the 1990s.

In fact, the experiments conducted with LifeHand represent the final act of a specific journey that began in 2003, within the scope of the NEUROBOTICS research program.

Replicating the human hand is quite a challenge from an engineering standpoint. a natural hand, in fact, is moved by more than 30 muscles, has more than 10,000 sensors and can carry out extremely complex gripping, handling, exploration and communication tasks.

The group of engineers at the ARTS Lab of the Scuola Superiore Sant’Anna of Pisa, led by Professor Paolo Dario and by Professor Maria Chiara Carrozza, responded to the challenge by attempting to develop a biomechatronic hand that would satisfy a specific need: facilitating the social and professional reintegration of subjects who have had a limb amputated.

In the specific case, the task of the Scuola Superiore Sant’Anna of Pisa was to design and build, in time, various prototypes of biomechatronic hand, drawing up the classification algorithms of neural signals, defining the stimulation signals and co-designing the neural interfaces: all the components that enable the hand to move voluntarily and be perceived.

The biomechatronic hand used for the experimental protocol of LifeHand was renamed CyberHand. CyberHand features five anthropomorphic fingers equipped with proprioceptive and esteroceptive sensors. Each finger is moved by a single motor, which allows flexion and extension of the three phalanxes. An additional motor (for a total of 6 motors in the hand) is used for the opposing movement of the thumb, which is crucial for gripping objects.

Motors and sensors are controlled by electronic cards that regulate the functioning according to a hierarchical architecture whose highest level can be controlled directly from a PC that classifies neural signals.