Robot implementation of duty-cycle invariance in cricket calling song preference

Behavioural experiments with crickets show that female crickets respond only to the male calling songs with a syllable rate within a specific interval, further it has been discovered that their response is independent of the duty-cycle of the song. Previously a neural control model was posed, which was able to explain how the selectivity of songs with syllable rates within a certain bandwidth could be obtained. The model explained why female crickets´ response to calling songs was invariant to the duty-cycle of the songs. Here, we propose a new neural model, which is able also to account for the selectivity of a specific syllable rate and is invariant to the song duty-cycle. Implementing it on a small, mobile robot and using an analog electronic model of the peripheral auditory morphology of the female cricket as the sensor test the new model. The robot is placed under the same experimental conditions as the real crickets and it responds with phonotaxis to synthetic calling songs with syllable rates within a certain bandwidth similar to crickets. Further, the robot performs phonotaxis to songs with a syllable rate within the correct bandwidth independently of the duty-cycle of the song.