Multi-modal flapping robots demonstrate potential capabilities to accomplish assigned missions in confined indoor and outdoor environments. In this letter, inspired by the multimodal movement of insects, we report a multimodal tailless flapping wing robot capable of flying, crawling, self-righting and horizontal take-off. The robot has two pairs of wings, and achieves flight attitude stabilization and control through wing stroke-plane modulation. Terrestrial locomotion is accomplished through a hexapod crawling mechanism driven by a set of two geared motors. Horizontal take-off is achieved by flapping wings and stroke-plane modulation, it can reduce the fuselage height of the crawling mode, so that the robot can crawl through smaller gaps. Furthermore, this mechanism enables the robot to self-right in the event of overturning. Currently, the robot weighs 35.4 g, has a wingspan of 33 cm, and it could fly at a maximum speed of about 5 m/s or crawl on the ground at a speed of up to 30 cm/s. And the robot could endure up to 8.2 minutes in flight or over 60 minutes in crawling using an onboard battery. Experiments show that the robot has demonstrated the ability to flexibly transition between flight and crawling modes, and it could fly in intricate environments and crawl through small gaps.

A 165 mg coin‐size bionic water‐skating robot driven by piezoelectric (PZT) bending actuator is presented. The robot with light weight and elastic legs uses surface tension to keep itself on the water surface. The driving force produced by flapping wings enables it to glide easily due to tiny resistance coefficient of water surface. The robot consists of PZT bending actuator, four‐bar transmission structure, two flapping wings, four elastic legs and the body. The actuator bending at resonance frequency of 105 Hz achieves 346 μm displacement at the end of actuator at voltage of 280 V so that the flapping angle of the wings reaches 73° at that frequency. Tests show that, the maximum equivalent payload of robot is 830.6 mg, about five times of its own mass, before breaking the water surface, and the water drag when robot skates on the water surface is about 29 μN, 1.76% of its gravity. The maximum forward speed of the robot is measured as 151 mm/s.

A micromachined electrostatically suspended six-axis accelerometer, with a square plate as proof mass housed by a top stator and bottom stator, is presented. The device structure and related techniques concerning its operating principles, such as calculation of capacitances and electrostatic forces/moments, detection and levitation control of the proof mass, acceleration measurement, and structural parameters design, are described. Hybrid MEMS manufacturing techniques, including surface micromachining fabrication of thin film electrodes and interconnections, integration fabrication of thick nickel structures about 500 μm using UV-LIGA by successful removal of SU-8 photoresist mold, DRIE of silicon proof mass in thickness of 450 μm, microassembly and solder bonding, were employed to fabricate this prototype microdevice. A levitation experiment system for the fabricated microaccelerometer chip is introduced, and levitation results show that fast initial levitation within 10 ms and stable full suspension of the proof mass have been successfully demonstrated.

This letter presents the design, fabrication, and performance test of a fish-like underwater miniature robot directly driven by two piezoelectric actuators. Considering the different medium conditions and the ever-present challenge of waterproofing in underwater motion, the miniaturization of underwater robots is regarded as an innovative task. In this letter, by mimicking the swing of fish caudal fins to generate thrust, a piezoelectric actuator is used to directly drive the artificial fins. This robot merely consists of six components, including two PZT actuators, a pair of caudal fins, and two glass fiber fixtures. Such a design serves to streamline the process of assembly. The total mass of prototype miniature robot is only 0.8 g and has a body length (BL) of 4 cm. The robot has demonstrated its capacity for flexible and swift underwater movement. It can perform straight and turning movements underwater, with a maximum forward speed of 8.01 BL/s (32.05 cm/s) at a driving voltage of 180 V. It has a maximum payload of 0.84 g and minimum turning radius of 7.9 cm.

Robots on the order of insect‐scale are difficult to manufacture using MEMS technologies for sub‐millimetre structures or conventional methods for large devices beyond centimetres. This work presents an electromagnetically driven, monolithically fabricated, insect‐scale self‐lifting flapping‐wing robot for the first time. This robot is created using a simple monolithic method, by which most of the components are integrated and fabricated from a single sheet. Finally, the monolithic insect‐scale flapping‐wing robot can generate sufficient lift to take off.