A wireless controlled robotic insect with ultrafast untethered running speeds.

Running speed degradation of insect-scale (less than 5 cm) legged microrobots after carrying payloads has become a bottleneck for microrobots to achieve high untethered locomotion performance. In this work, we present a 2-cm legged microrobot (BHMbot, BeiHang Microrobot) with ultrafast untethered running speeds, which is facilitated by the complementary combination of bouncing length and bouncing frequency in the microrobot's running gait. The untethered BHMbot (2-cm-long, 1760 mg) can achieve a running speed of 17.5 BL s-1 and a turning centripetal acceleration of 65.4 BL s-2 at a Cost of Transport of 303.7 and a power consumption of 1.77 W. By controlling its two front legs independently, the BHMbot demonstrates various locomotion trajectories including circles, rectangles, letters and irregular paths across obstacles through a wireless control module. Such advancements enable the BHMbot to carry out application attempts including sound signal detection, locomotion inside a turbofan engine and transportation via a quadrotor.

A Millimeter-Scale Multilocomotion Microrobot Capable of Controlled Crawling and Jumping.

Insects and animals in nature generally have powerful muscles to guarantee their complex motion, such as crawling, running, and jumping. It is challenging for insect-sized robots to achieve controlled crawling and jumping within the scale of millimeters and milligrams. This article proposes a novelty bionic muscle actuator, where an electrical pulse is applied to generate joule heat to expand the actuator's chamber. Under the restoring force of the spring element, the chamber contracts back to the initial state to finish a complete cycle. The actuator can obtain high-frequency vibration under the high-frequency electrical signal. We propose a microrobot based on the novelty actuator to achieve controlled crawling and jumping over the obstacle of the millimeter-sized robot. The robot is fabricated with two actuators as a crawling module and one actuator as a jumping module, with a mass of 52 mg, length of 9.3 mm, width of 9.1 mm, and height of 4 mm. The microrobot has a maximum crawling turning velocity of 0.73 rad/s, a maximum jump height of 42 mm (10.5 times body height), and a maximum jump velocity of 0.91 m/s. This study extends the potential for applying the novelty bionic-muscle actuator to the microrobot.