Robotic worm could explore inside damaged buildings

Inspiration for the project comes from C. elegans, a simple, multi-cellular nematode worm that is used as a research tool by biologists.

‘I was just taken by how robust the locomotion was, despite the remarkable simplicity of the control system,’ project lead Dr Jordan Boyle of Leeds University told The Engineer. 

The team first looked at the how the worm’s pared-down nervous system, which contains just 302 fully mapped neurons, controls its movements.

Still, Boyle said he was able to further simplify the control and translate this into models and algorithms for a prototype worm.

At 2m, the device is actuated by 12 geared DC motors that are distributed along its length to instigate the left-right bending action.

‘When appropriately co-ordinated, [this] causes a travelling wave to propagate from the head to the tail and that’s what generates the propulsion,’ said Boyle.

’Rather than sensing the external world and creating an internal representation, which requires intensive computations, the worm ‘implicitly adapts’ to its surroundings through its wave-like movements,’ he added.

The team is now working on improving the design. According to Boyle, the most recent prototype ‘cheats’ by using passive wheels to allow it to move. 

‘One of the requirements in terms of physics for undulatory locomotion is you need to have some way of achieving a difference in friction in the forward direction versus the sideways direction to allow a net force.

‘I’m very interested in the idea of exploring artificial materials that have the same asymmetric friction properties as snakes’ scales, for example, but that’s a whole area of research in itself.’