Offshore wind power is more abundant and stronger than the onshore, and more and more research enthusiasms have been raised in recent years. However, there are still many issues in the utilization of the offshore wind power such as the cost of installations and maintenance and the ability to resist extreme weather conditions. In this article, an offshore hydraulic wind turbine generator with variable-diameter rotor is presented. The diameter of the rotor can be regulated according to the wind speeds to achieve the maximum power coefficient. The hydraulic energy working as the transmission medium can improve the output power quality. The high-speed gearbox is removed, and the generator is installed on the platform, which facilitates the installations and maintenance. Here, the power conversion principle of the wind turbine generator was introduced first. Then, the dynamics and performance of the wind turbine generator was obtained. The relationship between the diameter of the rotor and the wind speed was established according to the dynamics and the optimum tip-speed ratio. Relying on the specific parameters, the dynamic response was calculated in Simulink. The results show that the instantaneous output of the wind turbine generator is relatively stable. Based on the power recovery method, the test platform was built, and the efficiency of the energy conversion device was tested. The experimental results demonstrate that the efficiency of the energy conversion device can be 88%. Finally, the total efficiency of the offshore hydraulic wind turbine generator was predicted to be 33.7%.

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The cascading launch and cooperative work of lander and rover are the pivotal methods to achieve lunar zero-distance exploration. The separated design results in a heavy system mass that requires more launching costs and a limited exploration area that is restricted to the vicinity of the immovable lander. To solve this problem, we have designed a six-legged movable repetitive lander, called “HexaMRL”, which congenitally integrates the function of both the lander and rover. However, achieving a buffered landing after a failure of the integrated drive units (IDUs) in the harsh lunar environment is a great challenge. In this paper, we systematically analyze the fault-tolerant capacity of all possible landing configurations in which the number of remaining normal legs is more than two and design the landing algorithm to finish a fault-tolerant soft-landing for the stable configuration. A quasi-incentre stability optimization method is further proposed to increase the stability margin during supporting operations after landing. To verify the fault-tolerant landing performance on the moon, a series of experiments, including five-legged, four-legged and three-legged soft-landings with a vertical landing velocity of −1.9 m/s and a payload of 140 kg, are successfully carried out on a 5-DoF lunar gravity ground-testing platform. The HexaMRL with fault-tolerant landing capacity will greatly promote the development of a next-generation lunar prober.

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