Heterogeneous Self-Reconfiguring Robotics

Self-reconfiguring (SR) robots are robots which can change shape to match the task at hand. These robots comprise many discrete modules, often all identical, with simple functionality such as connecting to neighbors, limited actuation, computation, communication and power. Orchestrating the behavior of the individual modules allows the robot to approximate, and reconfigure between, arbitrary shapes.

This shape-changing ability allows SR robots to respond to unpredictable environments better than fixed architecture robots. Common samples of reconfigure ability in action include transforming between snake shapes for moving through holes and legged locomotion for traversing rough terrain, and using reconfiguration for locomotion. SR robots also show promise for a high degree of fault tolerance since modules are generally interchangeable. The robot can self-repair by replacing the broken unit with a spare stored in its structure if one module fails. When all modules are the same, the system is known as homogeneous.

This design difficulty promotes fault-tolerance and versatility. However, a homogeneous system has limitations; all resources that may be required must be built into the basic module. We would like to relax the assumption that all modules are identical and investigate heterogeneous systems, where several classes of modules work together in a single robot. The heterogeneous systems can retain the advantages of their homogeneous counterparts while offering increased capabilities. The benefit would be a robot that can match not only structure to task by changing physical configuration, but also capability to task by using specialized components.

The future consideration application in which exploration tasks are carried out by SR robots. When necessary, the robot reconfigures into a legged walker to move across rough terrain or rubble, or transforms into a snake shape for moving through small holes. The robot can take advantage of smooth terrain as well by deploying a special module type containing wheels for fast, efficient locomotion. A variety of sensors are onboard, contained as modules within the structure of the robot.