Multidimensional Tunable Mechanics Using Jamming

Jamming is a structural phenomenon that provides tunable mechanical behavior. A jamming structure typically consists of a collection of elements with low effective stiffness and damping. When a pressure gradient, such as vacuum, is applied, kinematic and frictional coupling increase, resulting in dramatically altered mechanical properties. This results in a number of functional capabilities useful for robotics applications including: tunable stiffness, tunable force threshold, tunable dynamic response, reversible plasticity, shape locking, and variable kinematics. Engineers have used jamming to build devices from conformable grippers to tunable-stiffness haptic interfaces. This talk takes a multidimensional approach to the modeling and design of jamming-based structures. It introduces novel jamming-based structures with programmable tunable mechanical properties in specific degrees of freedom, enabling hybrid force/position control during robot-environment interaction. It presents a rigorous framework that systematically guides the design of jamming structures of major types (i.e., grain, fiber, and layer) for target applications. And finally, it presents a study that utilizes jamming-based structures to explore how people haptically engage with state-changing objects.