Design of a hover-capable flapping wing micro air vehicle with abdomen-wing coupled control

Insects and hummingbirds can achieve agile maneuvers through concomitant control of the abdomen and wings. However, hover-capable Flapping Wing Micro Air Vehicles (FWMAVs) inspired by insects and hummingbirds primarily rely on wing motion modulation, leading to insufficient control torques and poor maneuverability. To address this problem, we propose the BH-Fly, a hover-capable FWMAV with a novel abdomen-wing coupled control strategy. The BH-Fly weighs 32.5 g with a wingspan of 22 cm and can hover over 5 min with onboard batteries. The abdomen-wing coupled control is implemented through a linkage mechanism that synchronously rotates the abdomen and wing root. Experimental results show that this novel control strategy generates maximum pitch and roll torques of 6.3 N·mm and 7.8 N·mm, respectively, improving control torques by 26 % and 56 % over the existing hover-capable FWMAVs. Gimbal tests reveal that the BH-Fly achieves a maximum roll rate and angular acceleration of 35.48 rad/s and 175.47 rad/s², respectively. This enables the BH-Fly to complete a 360° turn in 0.18 s or about 4 flaps. Moreover, the dimensionless values of the maximum roll rate and angular acceleration match those of real hummingbirds. These findings demonstrate that the abdomen-wing coupled control provides a more biomimetic and efficient strategy for hover-capable FWMAVs.