At tonight’s meeting, the Drive and Sensor teams began to move from the requirements we worked out last week, to early design sketches.

The Drive team began with some exploration of existing drive systems, with a priority of keeping cost and complexity low. Our preliminary requirements call for a simple differential drive system, which provides linear motion and turning. However, we were reluctant to give up lateral movement capability. If possible (and practical), we’d like to adapt a proven drive system to connect with a standard interface of our own design. This modularity would permit us to swap drive systems easily, enabling future upgrades as well as potentially helping us to meet our single-part weight constraints. If we do not find a suitable existing drive system to adapt, we’ll consider building either a two-swerve + two-caster system, or a ball drive.

On the Sensor team, specific types of sensors were selected, and software packages identified that can leverage them. The current plan includes ultrasonic and IR sensors for distance measurement and proximity detection, Raspberry Pi cameras, low-cost LIDAR, and a depth camera. These would feed into our own control software, as well a stereo vision module, OpenRatSLAM for visual odometry and the gmapping package for ROS.

The Structure team will meet later this week to discuss physical design. Yet to be discussed are Computer requirements, but those will become clearer after the Software and Sensor teams refine their designs.