Grundfest A novel pneumatically-driven thin film balloon-based haptic feedback system is proposed for the restoration of haptic information for lower-limb amputees and for patients with lower-limb diabetic sensory neuropathy. The system envisioned here uses human skin and its associated sensors as an information conduit to the brain. Preliminary research has demonstrated the feasibility of a pneumatic balloon-based system, which features actuator arrays formed from macromolded polymer bases housing microfluidic channels and thin film silicone balloon membranes. Tactile information received from force sensors at the base of a lower-limb prosthesis will be integrated with a pneumatic control system and the balloon actuator system, which will be attached to the skin to provide haptic feedback. The actuator design is lightweight, compact, flexible, and can be scaled for the desired location. It also features large deflection and surface conformation, and can operate for thousands of cycles. An additional advantage of the balloon stimuli is that, due to its spherical and compliant nature, it applies a force with a large contact area, providing more tactile information than can be achieved with typical rigid cylindrical actuators. Individuals with lower-limb sensory loss due to amputation, neuropathy, or other disabilities experience decreased mobility and non-optimal gait, even with the application of prosthetics and orthotics. While great strides have been made to correct deficits in gait and motion through the development of artificial limbs and physical therapy, no effective method of sensory feedback exists. This proposal hypothesizes that a pneumatic, balloon-based haptic feedback system applied toward a lower-limb prosthetic system will shorten and improve rehabilitation by providing the patient with a previously unavailable tactile awareness. The haptic feedback system will provide additional tactile information that, with physical therapy, may improve gait and balance functions. This system is scalable and adaptable to a broad range of surfaces and environments, providing flexibility in design and implementation. Other applications include the use of the haptic feedback array as a method of localized tactile stimulation for a broader use in rehabilitation medicine, industrial robotic control, robotic surgery, virtual reality, and telepresence.
