Hopping Robot: Current Status and Future Perspectives

Background: Search and rescue in high-risk situations and searches in unknown environments pose certain threats to human life. The development of mobile robots with exploratory capabilities that can be adapted to complex sites with high mobility and high obstacle-crossing capabilities is, therefore, a research trend. Existing wheeled and tracked mobile robots have excellent locomotion, but they are less adaptable and less efficient when faced with complex terrain or outer space environments. Therefore, how to increase the obstacle-crossing ability and improve the movement efficiency of mobile robots have become a research hotspot in the field of mobile robotics. Objective: To introduce the classification, characteristics, and the development of the existing hopping robots. Methods: The various products and patents of hopping robots are summarized, and the structural features, differences, and applications of typical hopping robots are introduced. Results: By analyzing a variety of hopping robots, the typical characteristics and the current problems of hopping robots are analyzed, the development trend of hopping robots is prospected, the current research status of hopping robots is discussed, and the future prospects are carried out. Conclusion: Hopping robots can be divided into mechanical energy driven, combustion energy driven and new energy-driven according to the drive energy sources. Depending on the drive energy used, jumping robots can achieve a jump height 0.5-30 times higher than their own size, and when combined with a specific mechanical structure design, they are highly explosive, have high mobility and can solve interstellar exploration, terrain exploration and rescue problems. Compared to mechanical energy driven technique, combustion energy-driven technique is two orders of magnitude more energy-intensive than even the highest performing batteries. The use of recycled, renewable energy solves the energy self-loading problem of combustion energy driven drives and is more environmentally friendly than the two previous types of new energy drives. Therefore, such products should be invented and patented in the future.