A hybrid plastic-fabric soft bending actuator with reconfigurable bending profiles

Rigid actuators that accompany traditional robotic systems allow them to perform tasks with unmatched precision and efficiency. However, such systems are inapt when flexibility and suppleness are required. Inversely, soft robotic actuators are constructed out of naturally compliant materials. This compliance allows them to execute complex motions while their inherent lack of hardness removes the dangers that commonly accompany traditional robots. One archetype of the soft robot is the pneumatic bending actuator. The actuators convert the flow of pressurized air into bending outputs; however, most bending actuators are only limited to one bending trajectory. A new bending actuator, capable of active reconfiguration, is realized through the combination of a non-inflating, flexible, plastic spine and multiple, inflatable, fabric modules. The spine acts as the primary conduit and is responsible for distributing the pressurized flow to the modules. Modules can be removed and replaced seamlessly. The combination of varying module geometries can produce a heterogenic bending trajectory. Blockages located along the spine can separate flow, allowing more customization of the trajectory. A physical model predicting the pressure-bending relationship was conceptualized and verified. When pressurized to 100kPa, the 5-module and 10-module actuators achieved bending angles of 48.76° and 137.65° respectively. The actuators behave as a first-order system when supplied with a step input.