Integrated wave power charging capability for ocean observing vehicles

Adoption of autonomous underwater vehicle technology has recently experienced rapid growth. They are particularly useful as unmanned survey platforms and typically have an array of onboard sensors to collect data for a variety of commercial and military applications. Autonomous underwater vehicles require a power source, typically batteries, to be carried onboard. An increase in available energy is game-changing for autonomous underwater vehicles, with benefits including longer mission durations, higher sampling rates, expanded sensing capability, and improved communications. The problem of finite battery life can be addressed by allowing the vehicle to extract energy from its surrounding environment and eliminating the need to recover the vehicle until the mission is complete. This project aims to develop a system that will recharge the vehicle using the energy in ocean waves. Such a system can be integrated into commercial autonomous underwater vehicles and will greatly increase the science that can be accomplished, representing a significant commercial opportunity. In Phase I, a concept design was completed for a subsystem that will allow autonomous underwater vehicles to self-recharge from ocean waves. In Phase II it was demonstrated through laboratory experiments that this system could produce several watts of power on average, even in common, moderate wave conditions, meeting the commercial partner’s requirements. Detailed engineering design for the mechanical systems has since been completed, while work is still ongoing to complete the power electronics. Bench testing of the drivetrain has also been carried out, indicating that while the drivetrain is able to achieve the desired functionality, more work is needed to achieve the target efficiency. In Phase IIA, the team will focus on resolving the efficiency challenges with the power electronics, including identifying an improved custom motor/generator. The team will take the opportunity to further refine the hardware based on learning from Phase II tests. This will result in a new, improved wave-based charging module, which will then undergo comprehensive ocean testing. The concept adaptability will also be demonstrated by working with a different vehicle partner to modify the design of the system to fit a different, larger vehicle.: The addition of a self-recharging capability to ocean observing vehicles can make a meaningful impact on their performance by extending mission duration and improving sensing capability. In addition to improving the capabilities of the growing ocean observing space, this can help open up wave energy as a viable new renewable energy source, resulting in new high-paying manufacturing jobs.