This research project will employ an effect called laminar jamming to create robotic structures that controllably transition between highly compliant and nearly rigid. Precise position control typically requires rigidity, while safe and comfortable interactions with humans requires compliance. The need to incorporate both characteristics arises, for example, in assistive applications such as tremor suppression in Parkinson's disease. It is also necessary for robots working collaboratively with humans in manufacturing settings. Laminar jamming structures are composed of multiple parallel layers that ordinarily slide easily over each other. However, when the laminar structure is squeezed the layers become locked together by friction forces. This project will derive computationally tractable models of laminar structures under external forcing, to enable parametric design and real-time control. Fabrication of laminar jamming devices is simple and inexpensive, lowering barriers to widespread use, both in commercial applications and in educational settings. To ensure dissemination of the results, reference designs, configurations of jamming elements, application prototypes, and testing and performance data will be posted on a popular soft robotics website.
The combination of laminar jamming and soft robotics opens an entirely new range of robot designs and behaviors. Because the bending stiffness of a beam is proportional to the third power of its thickness, even a few laminae can produce dramatic increases in stiffness when jammed. The goal of this project is to define the capabilities of the technology and derive and validate the fundamental underlying principles. The project consists of three research subtasks: actuator design and testing, computational and analytical modeling, and implementation of key applications. The results of the project will provide a rich set of building blocks for robots that combine the advantageous features of both soft and rigid robots.