A flexible and innovative platform for autonomous mobile robots

Abstract

The development of the CREAL programming language and the STACK hardware platform by the members of the CSAIL Living Machines research group has lead to a foundation upon which roboticists may build and control autonomous mobile robots. This platform, however, has been used only within this research group on a minimal number of projects. As is, there has been no published discussion on the application of CREAL and the STACK to various types of control architectures commonly used in controlling autonomous mobile robots, or any personal accounts of the successes or failures of using such a system on a hand-built robot. In this thesis I focus on these two points. I go into depth on the use and expansion of CREAL to support multiple control architectures, as well as a personal account of the construction and use of a robot that uses these architectures and hardware to accomplish various tasks. The work to be undertaken will describe the process of design, construction, debugging and implementation of a hand-built robot that performs example tasks that are similar in nature to tasks commonly performed by autonomous mobile robots within the robotic research community. Currently, CREAL does not provide any abstract framework to facilitate implementation of neural net architectures by users. The work described in this thesis includes a set of macros that expand the CREAL language to allow user-friendly creation of neural nets. This abstraction framework is then put into use in an implementation that uses the neural net tools developed in order to achieve a fixed goal The second architecture to be discussed is that of subsumption, an architecture that is extremely well suited to be implemented in CREAL.

(cont.) To demonstrate the suit- ability of CREAL, a subsumption implementation will be described that performs a complex robot behavior An account will be given of creating a subsumption base behavior and passing through nmultiple stages that increment the behavioral capabilities of the robot. This will include a description at each stage of how the subsumption architecture is expanded to bring the behavior of the robot closer toward the goal behavior. Through the implementation of the above tasks I hope to show to be true what we have claimed: that the platform consisting of the CREAL programming language and the STACK hardware is an effective, flexible, powerful and desirable platform to use in designing autonomous mobile robots.