Book Description

Robotic design, especially in underwater robots, is critical to research, national defense, deep sea exploration and sea disaster rescue. Developing an advanced underwater robot, however, is complicated, as it involves propulsion, depth regulation, motion between propellers and other auxiliary system coordination, as well as sensing and feedback signals synchronization. Additionally, it is more challenging to manage the aquatic environment and guarantee the robotic design. In particular, the propulsion system could fit well in this environment and allow for efficient swimming. These challenges make the development of an underwater robot much more difficult, and finding the best solutions to building a robot in a standard and robust manner is critical to satisfying the large amount of requirements of the underwater robots in different perspectives. Aquatic creatures have developed swimming capabilities far superior in many ways to what has been achieved by nautical science and technology and have inspired alternative ideas of developing smart and advanced novel robotic mechanisms for propulsion in different fluid environments. Many bioinspired aquatic robots mimic the structure design, locomotion behaviors and even control method of their counterparts in nature and achieved great swimming performance. The further development of a more general design methodology for bioinspired underwater robots, however, has been impeded due to the diversity of biological sources for underwater propulsion. Consequently, there have been several studies attempting to understand basic propulsion principles to synchronize the biological diversity. In this dissertation, we first review the current stages and challenges of design of underwater robots. Afterwards, we provided a methodology for the design of efficient underwater robots from a biological perspective at multiple scales. To achieve this goal, we introduced the unique propulsion features of aquatic species in terms of locomotion mechanism as the swimmer increased in size from the micro/nanoscale to the macro-scale. Then, we discussed the biological propulsion principles for aquatic robotic design, including design of propeller, body, propulsion appendages, locomotion control and auxiliary system. In addition, we introduced the method for the implementation of bioinspired robots, including mechanical design, electronic engineering and system integration (Chapter 1). The following chapters show that four aquatic robots from the micro/nanoscale to the macro-scale were designed by learning unique features from biology and providing specific investigation of propulsion principle for robotic design at each scale. We validated and demonstrated the design of each robot using both mathematical model based simulation and hardware implemented robot experiments. In chapter 2, propulsion was investigated at micro/nanoscale (body length10-2m). Due to the constraints imposed at micro/nanoscale which has low Reynolds number (Re