Impedance-matched energy-harvester/sensor nets--- on sea floor and on land
Abstract
Proposed work uses impedance-matched energy converter+sensor nets on the seafloor and on land.The seafloor energy converters are des,igned for optimal energy conversion from surface-wave fieldsand the terrestrial energy converters are designed to convert optimal en,ergy from wind loads. Theproposed seafloor energy converters are distinct from conventional wave energy converters in thatthey utili,ze both first-order vertical pressure oscillations in littoral depths and second-order verticalpressure oscillations due to mixed se,as in deep waters. Pressure oscillations on seafloor excite energyconverter pulsations, which in turn drive small actuators that pro,duce useful power. Similarly, windpressureoscillations about mean and wind gusts cause tree stems and branches to oscillate, driving,several small actuators for energy conversion.In both settings, best conversion is available when the converter pulsations resonate,with the pressureoscillations and the energy conversion rate matches the energy input rate. Active control using theenergy-convertin,g actuators to provide both resistive and reactive forces extends natural impedancematching conditions to a wider frequency range ty,pical of usual wave and wind variations. Powerconverters charge batteries and drive a range of sensor operations, including seafloor, hydrophones andpressure transducers and other sensors to enhance situational awareness. The goal of the proposedwork is to put in p,lace the fundamental methods that will (i) result in self-sustaining persistent andon-demand (distributed) sensing, and thereby (ii), enhance cost-eectiveness of Naval operations.Our first objective is to develop techniques to optimize the energy harvesting and se,nsing performanceof seabed located sensor nets. Thus, it is proposed to investigate possible deployment of seabed locatednets of pre,ssure transducers, hydrophones, and small energy converters for persistent maritime sensingoperations in littoral (water depths 60,m) and deep (water depths 1000m) waters.Our second objective is extend the above techniques to terrestrial objects that are built,to mimictrees and bushes and utilize the large number of branches and leaves as well as the stems to convertwind power under impedan,ce matching control. Actuators for energy harvesting and sensorsfor environmental measurements are distributed throughout and attach,ed or embedded at optimallocations.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Apr 01, 2022
- Source ID
- N000142212373
Entities
People
- Umesh A. Korde
Organizations
- Johns Hopkins University
- Office of Naval Research
- United States Navy