A quick break from the semi-rigorous robotics discussion… Hex bugs were cool. Not just the tiny ones that were just bristles and a vibromotor but the slightly larger toys.
Specifically I had (have) two larvae and one of their beetles.
Hex Bugs: Larva (green), Beetle (orange), and Larva (blue)
They really are ingenious mechanical contraptions. The beetle is just a motor but via body and gearbox design it produces interesting movement behavior over slightly bumpy terrain. The beetle was designed to be fast and it delivers but at the cost of only moving in a single direction. Whereas the larva can only move slowly but its equipped with a proximity sensor that allows it to detect a collision and turn. And all with a single motor no less. The mechanism depends on direction the motor is spinning to engage a clutch gear. If only one of the wheels has the clutch the robot turns while its reversing. It may not turn the right way but if that’s the case it will just keep on turning.
I think these simple toys highlight a key principle for robotics, we don’t necessarily need sophisticated software/control if we choose an elegant mechanical design that fits our desired behavior goals.
