Curtis Rusch Senior Research Engineer crusch@apl.washington.edu Phone 2066165412 
Biosketch
Curtis is a Senior Research Engineer in the Ocean Engineering Department at APLUW. His research focuses on the generation of power from ocean waves, and the methods to apply this power for scientific research. This work has included field testing, numerical modelling, and experimental testing. Most recently, he has worked on a moored deployment of a wave energy converter that serves as a docking platform for a UUV, and has supported the development of a hardware interface to aid in autonomous docking and wireless recharge of an AUV. His PhD work focused on better understanding the hydrodynamics of heave plates for two body, point absorber wave energy converters.
Education
B.S. Mechanical Engineering, University of Washington, 2015
M.S. Mechanical Engineering, University of Washington, 2019
Ph.D. Mechanical Engineering, University of Washington, 2021
Videos
Using a Wave Energy Converter for UUV Recharge This project demonstrates the interface required to operate, dock, and wirelessly charge an uncrewed underwater vehicle with a wave energy converter. 
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11 Apr 2022


Uncrewed underwater vehicles (UUVs) predominantly use onboard batteries for energy, limiting mission duration based on the amount of stored energy that can be carried by the vehicle. Vehicle recharge requires recovery using costly, humansupported vessel operations. The ocean is full of untapped energy in the form of waves that, when converted to electrical energy by a wave energy converter (WEC), can be used locally to recharge UUVs without human intervention. In this project we designed and developed a coupled WECUUV system, with emphasis on the systems developed to interface the UUV to the WEC. 
Publications 
2000present and while at APLUW 
The next wave: Buoy arrays for deterministic wave prediction in realtime Thomson, J., A. Fisher, and C.J. Rusch, "The next wave: Buoy arrays for deterministic wave prediction in realtime," In Proc., IEEE/OES 13th Current, Waves and Turbulence Measurement (CWTM), 1820 March 2024, Wanchese, NC, doi:10.1109/CWTM61020.2024.10526333 (IEEE, 2024). 
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15 May 2024 

This work uses sparse arrays of ocean wave buoys to create a linear reconstruction of the sea surface and provide deterministic wave predictions at a future time and nearby position (i.e., within a few wavelengths). The predictions are constrained to be within the statistics of recently observed waves. This recently established method is applied in postprocessing at two distinct projects related to 1) a wave energy converter and 2) an offshore wind platform. The conditions range from scalemodel tank testing to an operational openocean wind farm. Relative to a conventional statistical forecasting with random waves, the method achieves at least 60% improvement in prescribing the next several waves arriving at a given target location. Work is ongoing to implement this method in realtime, using radio modems to transmit raw motion data (5 Hz sampling) from the buoy array to a central node that continually updates a 30second prediction window with less than 1second latency. The deterministic wave predictions can be used to improve control strategies for platforms at sea, with improvements in efficiency and reductions in dynamic loads. 
A unified simulation framework for wave energy powered underwater vehicle docking and charging Chen, M., R. Vivekanandan, C.J. Rusch, D. Okushemiya, D. Manalang, B. Robertson, and G.A. Hollinger, "A unified simulation framework for wave energy powered underwater vehicle docking and charging," Appl. Energy, 361, doi:10.1016/j.apenergy.2024.122877, 2024. 
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1 May 2024 

As wave energy conversion technology advances, recharge of autonomous underwater vehicles has emerged as a promising application for this atsea power. We bring together an interdisciplinary team to create a simulation framework linking hydrodynamic modeling, autonomous docking and navigation algorithms, and a power tracking model to better understand how a full wave energy converter–autonomous underwater vehicle system could be modeled. A floating point absorber wave energy converter is modeled and analyzed under various wave conditions. We incorporate three different dock designs, using the modeled dock motion and simulated waveinduced currents to test our autonomous docking algorithm. We couple the output of this algorithm to the hydrodynamic model to simulate autonomous docking. This shows that docking with a floating third body is successful in most sea states, while a dock rigidly mounted to the wave energy converter presents difficulty for autonomous docking. Finally, we incorporate a power model to better understand the feasibility and capabilities of a wave energy converter–underwater vehicle system in simulated wave environments. This shows that this system is comfortably supported in the majority of sea states, and provides an estimate of the onboard power storage required to maximize vehicle mission time. 
Effect of heave plate hydrodynamic force parameterization on a twobody wave energy converter Rusch, C.J., J. Joslin, B.D. Maurer, and B.L. Polagye, "Effect of heave plate hydrodynamic force parameterization on a twobody wave energy converter," J. Ocean Eng. Mar. Energy, 8, 355367, doi:10.1007/s4072202200236z, 2022. 
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12 Jun 2022 

Heave plates are one approach to generating the reaction force necessary to harvest energy from ocean waves. In a Morison equation description of the hydrodynamic force, the components of drag and added mass depend primarily on the heave plate oscillation. These terms may be parameterized in three ways: (1) as a single coefficient invariant across sea state, most accurate at the reference sea state, (2) coefficients dependent on the oscillation amplitude, but invariant in phase, that are most accurate for relatively small amplitude motions, and (3) coefficients dependent on both oscillation amplitude and phase, which are accurate for all oscillation amplitudes. We validate a MATLAB model for a twobody point absorber wave energy converter against field data and a dynamical model constructed in ProteusDS. We then use the MATLAB model to evaluate the effect of these parameterizations on estimates of heave plate motion, tension between the float and heave plate, and wave energy converter electrical power output. We find that power predictions using amplitudedependent coefficients differ by up to 30% from models using invariant coefficients for regular waves ranging in height from 0.5 to 1.9 m. Amplitude and phasedependent coefficients, however, yield less than a 5% change when compared with coefficients dependent on amplitude only. This suggests that amplitudedependent coefficients can be important for accurate wave energy converter modeling, but the added complexity of phasedependent coefficients yields little further benefit. We show similar, though less pronounced, trends in maximum tether tension, but note that heave plate motion has only a weak dependence on coefficient fidelity. Finally, we emphasize the importance of using experimentally derived added mass over that calculated from boundary element methods, which can lead to substantial underprediction of power output and peak tether tension. 
In The News
UW researchers finish tests on device hoping to harness wave energy The Seattle Times, Amanda Zhou For much of the past two months, every time he felt a gust of wind, University of Washington senior research engineer Curtis Rusch thought about the yellow device floating in Lake Washington. 
15 Mar 2024
