Lincoln Smith

Any experimentation on autonomous robots involves logistical issues of power supply, quantitative data collection, accuracy, ease of external monitoring, extraction of positional information, repeatability and procedural automation. The gantry system was designed as a tool to address these issues and allow easier investigation of real world navigation.

A gantry robot mitigates the problems associated with development on real world robots and offers possibilities for the development of real world robot controllers using evolutionary algorithms with the evaluation of behaviour taking place in the real world. In addition, the gantry is a data collection tool that can be used to capture views of complex scenes. When collected systematically these images can form a database indexed by position for use in offline simulation and algorithm development. Images can also be collected while traversing the recorded trajectories of real insects. This analysis tool is useful for both biological studies and bio-inspired navigation research.

The gantry system is a large volume three-dimensional cartesian robot. The axis configuration is set so that an operating volume of 3000 x 2000 x 2000mm is obtainable. The sensor end of the Z-axis can be placed anywhere within this volume with an sub-millimetre accuracy. The gantry system's key components are a 3-dimensional positioning system (XYZ axes), the drive electronics, a control computer, and the robot enclosure. The enclosure provides both the structural support on which the motion system rests and the barrier between the robot working space and the rest of the room. A separate electronics box holds the drive hardware for the motion system and the interface to the control computer.

As the robot moves about the workspace, data can be collected from the Z-axis mounted sensory head then viewed and/or stored on the computer. There is an mounting plate on the bottom of the Z-axis to which heads can be quickly switched out by loosening two thumbscrews. Access to the primary cable loom and all lines running back to the control computer is via quick connect style connectors.

The current sensory heads are camera based and do not contain any additional sensors. However, the primary cable loom that services the sensory head was designed for expansion with RS232, RS485, Composite video, digital io, USB, audio, S-Video, and 12v and 5v power supplies. As such, the sensory head is not limited to only input. It can interact with the environment via robotic appendages, grippers or the like. One application might see an entire existing mobile robot attached to the gantry Z-axis. The gantry system would perform movements to emulate those of the mobile robot based on the robot's controller. This might be used to automate highly repetitive experiments, or develop controllers on difficult to evaluate platforms (e.g. automous flying or underwater robots).