ABSTRACT
The intrinsic mechanical parameters of a cricket’s cercal wind receptor hair were determined from direct measurement of hair deflections. The hairs were modeled as an inverted pendulum, and the mechanical parameters of the equation of motion were determined from data given by the systematic measurement of mobility by the least-squares error sum method. The theoretical torque that deflects the hair shaft is given by the viscous force calculated from Stokes’s mechanical impedance of an oscillating cylinder in a viscous fluid. In response to the mechanical stimulus, a molecular transduction mechanism of the sensory cell generates a membrane potential and transmits a pulse train to the central nervous system. The inverted pendulum is a typical second order mechanical system that consists of a moment of inertia that represents the mass distribution along the hair shaft, a spring that provides the restoring torque toward a resting position of the hair, and torsional resistance within the hair base.
