'Pygmy shrew' robot navigates using tactile whisker sensors

Shrewbot is the latest application of the tactile robotic sensing technology pioneered by engineers at the universities of Bristol, Sheffield and Sheffield Hallam.

Speaking to The Engineer at the TAROS robotics conference in Sheffield, project lead Prof Tony Prescott (University of Sheffield) explained the potential importance of tactile navigation.

‘You can stare at a surface forever but you don’t know whether it’s safe to stand on. With something like a Mars lander, where you’re relying on vision, you can’t be sure that you’re not going to stand on quicksand, whereas if you have a touch sensor you can at least say it’s a solid surface,’ he said.

Rats and shrews have two main types of whisker sensors: longer macrovibrissae and shorter, more densely arranged microvibrissae. Although both types are capable of detecting tactile features such as texture and shape, there appears to be some specialisation of function. Specifically, the longer macrovibrissae serve as a highly effective means of pinpointing interesting objects in space, whereas the microvibrissal array may be the most optimal device for the close examination of surface properties.