We discuss a robotic system composed of Crystalline modules. Crystalline modules can aggregate together to form distributed robot systems. Crystalline modules can move relative to each other by expanding and contracting. This actuation mechanism permits automated shape metamorphosis. We describe the Crystalline module concept and show the basic motions that enable a Crystalline robot system to self-reconfigure. We present an algorithm for general self-reconfiguration and describe simulation experiments.

We present a randomized approach to path planning for articulated robots that have closed kinematic chains. The approach extends the probabilistic roadmap technique which has previously been applied to rigid and elastic objects, and articulated robots without closed chains. Our work provides a framework for path planning problems that must satisfy closure constraints in addition to standard collision constraints. This expands the power of the probabilistic roadmap technique to include a variety of problems such as manipulation planning using two open-chain manipulators that cooperatively grasp an object, forming a system with a closed chain, and planning for reconfigurable robots where the robot links may be rearranged in a loop to ease manipulation or locomotion. We generate the vertices in our probabilistic roadmap by sampling random con gurations that ignore kinematic closure, and by performing randomized gradient descent to force satisfaction of the closure constraints. We generate...

We discuss a basis for creating self-reconfiguring robots and instantiate it for Crystal modules. Crystalline robots consist of modules that can aggregate together to form distributed robot systems. Crystalline modules are actuated by expanding and contracting each unit. This actuation mechanism permits automated shape metamorphosis. We describe the Crystalline module concept and its physical implementation. We prove that Crystalline robots are general self-reconfiguring robots.

In this article we examine the problem of dynamic self-recon guration of a modular robotic system (frequently referred to as self-recon gurable or metamorphic system), to a formation aimed at reaching a speci ed target position as quickly as possible. We present a number of fast formations for both rectangular and hexagonal systems, and prove upper and lower bounds on the speed of locomotion. In particular, the formations presented here achieve a constant ratio guarantee on the time to reach a given target in the asymptotic sense.