Podcast with Maria Chiara Carozza on prosthetic hand and neurorobotics

What will it take to build a prosthetic hand that your brain accepts as part of your own body? Maria Chiara Carozza describes the frontier of neurorobotics, where artificial limbs must not only move on command but generate the sensory feedback that creates body ownership.

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Carozza defines human-robot symbiosis as a relationship where robot and user share the same objectives and are interdependent in performing tasks. Her Neuro-Robotics Research Group at Scuola Superiore Sant'Anna in Pisa develops wearable robots that read non-invasive signals, including surface electromyography, limb movements, eye tracking, and physiological indicators, to infer user intentions without surgical implants. The challenge extends beyond reading intent: the robot must also provide sensory feedback through wearable interfaces that stimulate the skin, enabling the user to perceive the environment through the artificial device.

The interview explores the rubber hand illusion as a bridge between neurophysiology and robotics. When visual and tactile signals are correlated, subjects develop body ownership for a rubber hand, experiencing a stab to the fake hand as if it were real. Carozza's team is translating this principle into prosthetic design by embedding vibrotactile stimulators inside the socket interface between stump and artificial hand. By mapping finger contact forces to specific stimulation patterns on the residual limb, they aim to create a learned association that could eventually migrate perceptually to the fingertips, leveraging the brain's remarkable capacity for adaptive remapping.

Carozza also describes exoskeletons for post-stroke rehabilitation, where an external articulated structure acts in parallel with the weakened natural limb. This parallel configuration creates a fundamental control problem: two manipulators must share the same goal and move in harmony, or the system fails and the patient rejects it. Success rates below 90% task completion are unacceptable because the remaining failures create frustration and social embarrassment. The iterative design process, driven by direct feedback from amputees and stroke patients, reveals that cosmetic appearance, lightweight construction, eight-hour battery life, and comfortable skin interfaces are as critical as motor performance.