| The work area of a team of small robots is limited by their inability to traverse a very common obstacle: stairs. We present a complete integrated control architecture and communication strategy for a system of reconfigurable robots that can climb stairs. A modular robot design is presented which allows the robots to dynamically reconfigure to traverse certain obstacles. This thesis investigates the implementation of a system of autonomous robots which can cooperatively reconfigure themselves to collectively traverse obstacles such as stairs. We present a complete behavior and communication system which facilitates this autonomous reconfiguration. The layered behavior-based control system is fault-tolerant and extends the capabilities of a control architecture known as ALLIANCE. Behavior classes are introduced as a mechanism for managing ordering dependencies and monitoring a robot's progress through a particular task. The communication system complements the behavioral control and implements inherent robot failure detection without the need for a base station or external monitor. The behavior and communication systems are validated by implementing them on a mobile robot platform synthesized specifically for this research. Experimental trials showed that the implementation of the behavior control systems was successful. The control system provided robust, fault-tolerant performance even when robots failed to perform docking tasks while reconfiguring. Once the robots reconfigure to form a chain, a different control scheme based on gait control tables coordinates the individual movements of the robots. Several successful stair climbing trials were accomplished. Improvements to the mechanical design are proposed. |
