Silkmoth Drives a Robot to Track Sex Pheromones
A small robotic car with two wheels was "driven" by a male silkmoth, which used it to track down the sex pheromone usually given off by a female mate.
The experiment is aimed at characterising the silkmoth's tracking behaviours and it is hoped that these can be applied to other autonomous robots so they can track down smells, and the subsequent sources, of environmental spills and leaks when fitted with highly sensitive sensors.
"The simple and robust odour tracking behaviour of the silkmoth allows us to analyse its neural mechanisms from the level of a single neuron to the moth's overall behaviour," says Dr Noriyasu Ando of the University of Tokyo.
"By creating an 'artificial brain' based on the knowledge of the silkmoth's individual neurons and tracking behaviour, we hope to implement it into a mobile robot that will be equal to the insect-controlled robot developed in this study."
The researchers attached the silkmoth to a free-moving polystyrene ball at the front of the robot which was used for overall control. Two fans wafted the pheromone-containing air towards it.
A 1800 millimetre wind tunnel was used, with the pheromone and robot at opposite ends; fourteen silkmoths were used altogether,and all were able to successfully guide the robot towards the source.
Chemical sensors vary in the amount of time they take to respond, so the team looked at the effect of a time delay between the movement of the silkmoth and the response of the motor.
"Most chemical sensors, such as semiconductor sensors, have a slow recovery time and are not able to detect the temporal dynamics of odours as insects do," says Ando.
"Our results will be an important indication for the selection of sensors and models when we apply the insect sensory-motor system to artificial systems."
The results have been published today, 6 February, in IOP Publishing's journal Bioinspiration and Biomimetics, and include a video of the robot in action https://www.youtube.com/watch?v=n2k1T2X7_Aw