Flight Behavior Control Of Bumblebees By Electrical Stimulation On Anterior Optic Tubercles

The insect-machine interface has been used to study the neural circuits. It can also be used in free moving insects and induces expected actions of the insects by electrical stimulation, optical stimulation or chemical stimulation. The robots which combine the outstanding capacity of insects’motion and the control of computing system are called cyborg insects. This thesis uses bumblebees as the locomotion platform of cyborg insect, and focuses on electrical stimulation on the upper subunit of anterior optic tubercle. Electrical stimulation on anterior optic tubercle can induce wing oscillation and abdomen swing of bumblebee. The half-tethered experiment has been conducted to verify the effect of stimulation on flight behavior, and an electric stimulating backpack is developed.The initiation and cessation of wing oscillation on tethered state can be induced by the bilateral brain regions electrical stimulation.1 OOHz,40% duty cycle,Is positive and negative square wave pulse sequence were used in the experiments. The voltage has been changed depending on its effect to wing oscillation. The success rate of wing oscillation initiation on tested bumblebee is 55% (N=20). It is found that the voltage threshold of wing oscillation initiation is at least 2.0V, and the success rate is relatively high on 3.0-5.0V. The response time, oscillation duration and oscillation frequency have been recorded too. It is found that with the increase of voltage, response time increases and oscillation frequency decreases, while oscillation duration first increases and then decreases.Abdomen swing of bumblebee can be induced by the unilateral brain regions electrical stimulation. The abdomen will swing to the same direction with the stimulation site. The amplitude of swing increases when voltage and duration of stimulation increase. The abdomen swing is an important control method of insect flight steering. The experiment result shows that this kind of stimulation can induce flight steering to the same direction with the stimulation site.At last, a half-tethered electrical stimulation experiment has been conducted to verify that the stimulation parameters obtained from tethered state can initiate bumblebee flight stably. In addition, a stimulating backpack is designed. The backpack weighs 158mg. Bumblebee can creep free with the payload of backpack.