The Steering Jump Control of a Locust Bio‐Robot via Asynchronous Hindleg Kickings

Abstract

The locust's steering behavior has long been thought to be achieved under the control of fore‐ and mesothoracic legs before takeoff. This turning strategy is not necessarily present in all steering jumps. It is found that the locust could achieve a large‐angle steering jump without significant yaw rotation beforehand. Herein, how the hindlegs contribute to the steering jump, including kinematic analyses and reaction forces measurement, is studied. It is found that the contralateral hindleg of the turn direction presses down tens of milliseconds earlier than the ipsilateral side. The time lag between both hindlegs is primarily responsible for the steering jumps. The leg kickings with a time lag is induced exogenously by designing sequential electrical stimulation signals for the muscles of both legs. Under 0‐ms, 20‐ms, and 40‐ms time lags, the induced steering angles are 2.1°, 22.1°, and 24.2°, respectively, in the loosely tethered jumps. A locust is transformed into a bio‐robot via a custom e‐backpack and demonstrate a remote‐controlled 20° jump of the bio‐robot. The asynchronous actions of bilateral actuators for steering jumps are extremely beneficial for micro‐robots, as both the jumping and the steering functions can be compacted together.