The sandfish lizard moves very efficiently through the sands of the Sahara desert, and not surprisingly, it doesn't use wheels to do so. Scientists have now copied the reptile's swimming motion in an experimental Mars rover that outperforms others in sandy soil.
The prototype rover is part of the German Space Agency's VaMEx (Valles Marineris Explorer) program, which is an initiative aimed at developing swarms of driving, walking and flying robots designed to explore Mars' vast Valles Marineris valley.
And yes, the rover does in fact have wheels … but they aren't normal ones.
The sandfish lizard (Scincus scincus) "swims" through the sand by undulating its body from side to side, which is a motion that the University of Würzburg's Prof. Marco Schmidt set out to replicate in the vehicle's unique wheels. Those wheels do still roll, but they also wiggle, for lack of a better word.
Developed in partnership with the University of Bremen, the wheels were originally heavier and narrower than comparable conventional pneumatic wheels. This meant they had an inconvenient tendency to sink into the sand and to slip against it, hampering the rover's movement.
That problem was remedied by making them both lighter and wider, increasing their flotation while also reducing slippage. As a result, when traversing loose sand, the rover ended up outperforming similar vehicles that were equipped with conventional wheels.
Plans now call for further refinements to be made to the wheels, to enhance their performance on mixed terrain.
Source: University of Würzburg
