Modeling and Characterization of a Potential Bladder Based Orthotic Device to Mitigate Shoe Slip

The exploration of an “intelligent” orthotic shoe sole to negate, or minimize, longitudinal slip by momentarily increasing friction force is presented. The conceptual device takes the form of a rubberized shoe sole containing pockets of air that can be released via valves controlled by a microprocessor. During a slip event, the valves would be opened and the bladders would be collapsed by the weight of the user, which modulates contact and friction forces. The goal is to increase friction forces in this process, by creating an impact force between the user and ground surface, with the potential to increase friction and mitigate slip. Simulations of bladder walls, air flow through valves, contact forces, and friction forces are modeled and combined into a lumped parameter model to predict device behavior. Prototypes of the device are created and evaluated to validate models and slip-mitigating potential.