Energy Efficient Propulsion and Station-Keeping of Jellyfish Robotic Unmanned Underwater Vehicles
By Keyur Joshi
1. AJV Propulsion System Design and Modeling
- We are developing Autonomous Jellyfish Vehicles(AJVs) for underwater surveillance for U.S.Navy. We learn from nature and try to design engineering systems that mimic the the jellyfish biology. We model the system and optimize to achieve the best performace.
2. Modeling of Smart Materials and Structures
- For achieving biomimetic shape of jellyfish, we've developed some smart structures. The BISMAC (Bio-Instpired SMA Composite) shown in the figure above is one of the most successful. We've optimize the structure of BISMAC to match Jellyfish curvatures and to achieve most efficient swimming performance. The figure below shows similar modeling and optimization effort for IPMC(Ionomeric Polymer Metal Composite) actuators based Jellyfish.
3. Energy harvesting for AJVs
- Functionality and duration of task for surveillance vehicles operating in Underocean environment is limited by the available energy, usually battery storage. We are researching energy harvesting from different forms of energy available in Ocean to achieve truely independent, Autonomous Jellyfish Vehicles(AJVs). The figure on left represents schematic of the mathematical model for Solar energy harvesting and on the right is our visualization of these AJVs in action.The figures below depicts jellyfish feeding mechanism and our strategy to evolve engineering design to achieve this function.
4. Past Research
- On left is a subsonic wind tunnel with flow visulation capability and instrumented Airfoil self-designed and fabricated. The next figure is of one of most powerful aircraft engine, GE90-115B. I worked on some Low cycle and High cycle fatigue life analysis, crack propagation, Elastic-plastic analysis of structural components of this Engine.
- During M.Tech, I got chance to design and manufacture 2DOF Slosh Test Rig. Using the testrig, I develop simplified mathematical model for slosh for real-time control implementation. Using MATLAB's system identification toolbox and control toolbox, we successfully implemented simple slosh suppression strategies.