Meeting Abstract

P3.151  Sunday, Jan. 6  Dynamic response of antenna flagellum in the American cockroach DALLMANN, C.J.*; MONGEAU, J.-M.; JAYARAM, K.; MAHAVADI, A.; FULL, R.J.; Univ. of Bielefeld; Univ. of California, Berkeley; Univ. of California, Berkeley; Univ. of California, Berkeley; Univ. of California, Berkeley jmmongeau@berkeley.edu

The integration of information from sensory structures on a moving body during dynamic, high-bandwidth tasks is a challenge for locomoting animals and engineers seeking to design highly-mobile robots capable of autonomously navigating in natural environments. In locomotion-mediated tactile sensing both body and sensor dynamics must be quantified. We took the first step to elucidate the dynamic response of the sensor by studying the antennae of Periplaneta americana, a cockroach that escapes predators by integrating information from this sensory appendage in tasks such as wall following and collision avoidance while rapidly running up to 80 cm/s . High-speed videos of free vibration responses to initial deflections from five intact antenna flagella revealed a mean damped natural frequency of 18±3.0 Hz and damping ratio of 0.52±0.092. As the antenna was under-damped, 93.3% of the perturbation was rejected within the first cycle (69 ms), which corresponds to within one stride period during high-speed running. A linear, second-order model captured about 95% of the variance in the dynamic response. An impulse-like perturbation near the antennal tip revealed dynamics characteristic of a near perfect inelastic collision with antennal bending showing peak curvature close to the site of impact. Results suggest that antennae of P. americana are less damped than those of slowly walking stick insects, but more damped than vertebrate vibrissae. Further elucidating antennal mechanical tuning will lead to hypotheses integrating distributed mechanosensory inputs from a dynamic sensory appendage operating on a rapidly moving body and generate predictions about neural tuning and encoding.