Natural frequency analysis of rat whiskers

Rat whiskers, and their associated neural substrate, comprise a highly evolved bio-sensory system used to perceive the world with an acuity that matches human vision or hearing. Study of the whisker sensory system is becoming an attractive research topic due to its fundamental importance as a fine sensor in neuroscience and due to the potential to develop biomimetic robotics. In this paper, a truncated conical beam model is used to study the natural frequency of a rat whisker. In addition to the proof of two generic natural frequency relationships for a truncated conical beam, our numerical results show that there exists a window where the natural frequencies of a rat whisker are very sensitive to the change of the rotational constraint at the base. This has significance for the function of the sensor since the rat follicle constraints can be manipulated by a behaving rat, thereby altering the natural frequencies of the whisker.