Pub Date : 2015-10-01DOI: 10.23919/OCEANS.2015.7401961
N. Montazeri, U. Nielsen, Jørgen Juncher Jensen
This paper presents a trend analysis for prediction of sea state parameters onboard ships during voyages. Given those parameters, a JONSWAP model and also the transfer functions, prediction of wave induced ship responses are thus made. The procedure is tested with full-scale data of an in-service container ship. Comparison between predictions and the actual measurements, implies a good agreement in general. This method can be an efficient way to improve decision support onboard ships.
{"title":"Trend modelling of wave parameters and application in onboard prediction of ship responses","authors":"N. Montazeri, U. Nielsen, Jørgen Juncher Jensen","doi":"10.23919/OCEANS.2015.7401961","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401961","url":null,"abstract":"This paper presents a trend analysis for prediction of sea state parameters onboard ships during voyages. Given those parameters, a JONSWAP model and also the transfer functions, prediction of wave induced ship responses are thus made. The procedure is tested with full-scale data of an in-service container ship. Comparison between predictions and the actual measurements, implies a good agreement in general. This method can be an efficient way to improve decision support onboard ships.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114198512","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-01DOI: 10.23919/OCEANS.2015.7401986
Jin-Yeong Park, H. Shim, H. Baek, S. Yoo, B. Jun, Pan-Mook Lee
In west coast of Korea peninsula, there are some offshore sites where ancient sunken shipwrecks have been discovered. These ships are supposed to carry an amount of artifacts what show lifestyle and culture of the day. In these areas, however, because of fast ocean currents and low visibility, underwater survey and excavation by divers are strictly restricted. Especially, optical cameras and human's visual inspection become defective. To overcome these conditions, use of unmanned underwater vehicles such like a ROV(Remotely Operated Vehicle) which is equipped with acoustic imaging devices has been raised. This paper describes preliminary performance experiments for survey of underwater cultural heritages using a ROV whose name is Crabster driven by six artificial legs with a high-resolution acoustic camera in sea. The Crabster uses the six articulated legs actuated by BLDC motors as its thrusters. Therefore, it moves on the sea floor without disturbances by propellers which are widely used as thrusters of any other general ROVs. In addition, The robot is expected to minimize shadow areas of acoustic imaging sensors by controlling its body posture precisely using the legs. In this paper, we introduce operations of Crabster and the acoustic imaging devices when we conducted from April to May in 2015. Using acoustic imaging devices, we could find dispersed potteries and iron caldrons. Mosaicked image to show surround of the robot is also included.
{"title":"Multi-legged ROV Crabster and an acoustic camera for survey of underwater cultural heritages","authors":"Jin-Yeong Park, H. Shim, H. Baek, S. Yoo, B. Jun, Pan-Mook Lee","doi":"10.23919/OCEANS.2015.7401986","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401986","url":null,"abstract":"In west coast of Korea peninsula, there are some offshore sites where ancient sunken shipwrecks have been discovered. These ships are supposed to carry an amount of artifacts what show lifestyle and culture of the day. In these areas, however, because of fast ocean currents and low visibility, underwater survey and excavation by divers are strictly restricted. Especially, optical cameras and human's visual inspection become defective. To overcome these conditions, use of unmanned underwater vehicles such like a ROV(Remotely Operated Vehicle) which is equipped with acoustic imaging devices has been raised. This paper describes preliminary performance experiments for survey of underwater cultural heritages using a ROV whose name is Crabster driven by six artificial legs with a high-resolution acoustic camera in sea. The Crabster uses the six articulated legs actuated by BLDC motors as its thrusters. Therefore, it moves on the sea floor without disturbances by propellers which are widely used as thrusters of any other general ROVs. In addition, The robot is expected to minimize shadow areas of acoustic imaging sensors by controlling its body posture precisely using the legs. In this paper, we introduce operations of Crabster and the acoustic imaging devices when we conducted from April to May in 2015. Using acoustic imaging devices, we could find dispersed potteries and iron caldrons. Mosaicked image to show surround of the robot is also included.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"56 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121085682","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-01DOI: 10.23919/OCEANS.2015.7401936
Thomas C. Furfaro, J. Alves
This paper presents an implementation of a communications stack for underwater communications and relative localisation. The application scenario, under the auspices of the EC MORPH project, is described. The high-level architecture is described, with the relevant hardware and software implementation details. A summary of the localisation methods, based on previous works, is given, followed by a discussion of the encoding mechanism.
{"title":"A communications and relative navigation architecture for underwater vehicle coordination","authors":"Thomas C. Furfaro, J. Alves","doi":"10.23919/OCEANS.2015.7401936","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401936","url":null,"abstract":"This paper presents an implementation of a communications stack for underwater communications and relative localisation. The application scenario, under the auspices of the EC MORPH project, is described. The high-level architecture is described, with the relevant hardware and software implementation details. A summary of the localisation methods, based on previous works, is given, followed by a discussion of the encoding mechanism.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115276857","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-01DOI: 10.23919/OCEANS.2015.7404349
Kevin J. DeMarco, M. West, A. Howard
Divers have to perform technical underwater tasks in dangerous and unstructured environments. To reduce a diver's workload and improve overall safety, an underwater robotic assistant (UWRA) could be deployed with the diver. The UWRA could assist the diver in navigation, quickly ferry tools from the surface, and carry underwater samples. To develop and test the autonomy required for such a UWRA, autonomy developers could benefit from a simulated underwater environment. Unfortunately, a real-time simulation for one of the most important sensors in underwater robotics, a forward-looking 2D imaging sonar, does not exist in robotics simulators. We developed a simulation for 2D imaging sonars that executes in real-time in the Gazebo robotics simulator. The 2D imaging sonar simulator was assessed by comparing the sonar images that it generated with sonar images generated by real sonar systems in similar environments. For example, we tested both the simulated and real sonar systems in environments with underwater man-made structures, divers, and varying terrain. The sonar simulator was also assessed based on its computational complexity and compared to other similar simulators with respect to sonar image generation rates. We found that our 2D imaging sonar simulator generated qualitatively realistic images and that it was computationally efficient enough to execute in real-time with the Gazebo simulator.
{"title":"A computationally-efficient 2D imaging sonar model for underwater robotics simulations in Gazebo","authors":"Kevin J. DeMarco, M. West, A. Howard","doi":"10.23919/OCEANS.2015.7404349","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404349","url":null,"abstract":"Divers have to perform technical underwater tasks in dangerous and unstructured environments. To reduce a diver's workload and improve overall safety, an underwater robotic assistant (UWRA) could be deployed with the diver. The UWRA could assist the diver in navigation, quickly ferry tools from the surface, and carry underwater samples. To develop and test the autonomy required for such a UWRA, autonomy developers could benefit from a simulated underwater environment. Unfortunately, a real-time simulation for one of the most important sensors in underwater robotics, a forward-looking 2D imaging sonar, does not exist in robotics simulators. We developed a simulation for 2D imaging sonars that executes in real-time in the Gazebo robotics simulator. The 2D imaging sonar simulator was assessed by comparing the sonar images that it generated with sonar images generated by real sonar systems in similar environments. For example, we tested both the simulated and real sonar systems in environments with underwater man-made structures, divers, and varying terrain. The sonar simulator was also assessed based on its computational complexity and compared to other similar simulators with respect to sonar image generation rates. We found that our 2D imaging sonar simulator generated qualitatively realistic images and that it was computationally efficient enough to execute in real-time with the Gazebo simulator.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"192 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121714544","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-01DOI: 10.23919/OCEANS.2015.7404426
Isabel Andrade-Bustos, L. García-Valdovinos, T. Salgado-Jiménez, M. Bandala-Sánchez
The response of the ROGUE underwater glider controlled by a scheme called Sliding PD control is shown and described. This control law has been widely used in robot manipulators, quadrotors and underwater ROV's. This is a model-free and chattering-free controller that makes motion robust to disturbance and uncertainty. The ROGUE dynamic model calculated on the vertical plane take into account a ballast tank fixed at the buoyancy center, a movable mass capable of motion just along the longitudinal axis and eliminates the offset static point mass. These considerations simplify significantly the equations of motion. Through simulation results this nonlinear controller demonstrates that it ensures a steady glide by directly controlling the movable mass position along with the ballast mass.
{"title":"Sliding-PD control performance on autonomous underwater gliders","authors":"Isabel Andrade-Bustos, L. García-Valdovinos, T. Salgado-Jiménez, M. Bandala-Sánchez","doi":"10.23919/OCEANS.2015.7404426","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404426","url":null,"abstract":"The response of the ROGUE underwater glider controlled by a scheme called Sliding PD control is shown and described. This control law has been widely used in robot manipulators, quadrotors and underwater ROV's. This is a model-free and chattering-free controller that makes motion robust to disturbance and uncertainty. The ROGUE dynamic model calculated on the vertical plane take into account a ballast tank fixed at the buoyancy center, a movable mass capable of motion just along the longitudinal axis and eliminates the offset static point mass. These considerations simplify significantly the equations of motion. Through simulation results this nonlinear controller demonstrates that it ensures a steady glide by directly controlling the movable mass position along with the ballast mass.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116551056","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-01DOI: 10.23919/OCEANS.2015.7404424
Carlos E. Romero-Martinez, L. Abril Torres-Mendez, E. Martínez-García
This ongoing research focuses on providing skills based on motor-perceptual behaviors to an underwater vehicle in order to execute collision-avoidance trajectories in a more natural and intuitive way. An intuitive action can be seen as a reflex in humans and some animals. Reflexs do not involve a conscious reasoning at the time of execution, this is because a motorperceptual skill for a particular action has been already developed in the brain from a past execution. For the case of a robot, the analogy would be that, during a collision-avoidance action, no sensor feedback is needed to correct the robot's state, and thus there is no need of applying a control law to achieve the required locomotion. The direct consequence of this would be the reduction of robot cost while maintaining its performance. Our approach involves a training phase, in which a set of primitive curve trajectories, at different radius and velocities, parameterized in time and orientation, are performed by using a PD control. By applying a linear regression classifier, only those output control parameters that yield stable and accurate trajectories are fed to a knowledge database. These parameters are used to perform intuitive trajectories without using a control law. Preliminary results show the feasibility of our method.
{"title":"Modeling motor-perceptual behaviors to enable intuitive paths in an aquatic robot","authors":"Carlos E. Romero-Martinez, L. Abril Torres-Mendez, E. Martínez-García","doi":"10.23919/OCEANS.2015.7404424","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404424","url":null,"abstract":"This ongoing research focuses on providing skills based on motor-perceptual behaviors to an underwater vehicle in order to execute collision-avoidance trajectories in a more natural and intuitive way. An intuitive action can be seen as a reflex in humans and some animals. Reflexs do not involve a conscious reasoning at the time of execution, this is because a motorperceptual skill for a particular action has been already developed in the brain from a past execution. For the case of a robot, the analogy would be that, during a collision-avoidance action, no sensor feedback is needed to correct the robot's state, and thus there is no need of applying a control law to achieve the required locomotion. The direct consequence of this would be the reduction of robot cost while maintaining its performance. Our approach involves a training phase, in which a set of primitive curve trajectories, at different radius and velocities, parameterized in time and orientation, are performed by using a PD control. By applying a linear regression classifier, only those output control parameters that yield stable and accurate trajectories are fed to a knowledge database. These parameters are used to perform intuitive trajectories without using a control law. Preliminary results show the feasibility of our method.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114276922","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-01DOI: 10.23919/OCEANS.2015.7401884
Y. Hirakawa, T. Yoda, T. Takayama, T. Hyakudome, T. Nakatani
In recent days, the simultaneous operation of several AUVs is desired to realize widespread exploration in a navigation. As a method to realize the simultaneous operation, introduction the repeater vehicle called ASV (Autonomous Surface Vehicle) is proposed. The task of the ASV is to chase an AUV and to communicate with a support vessel. So, one ASV is needed for one AUV but several ASVs are monitored by one support vessel. The size of the ASV is similar to the AUV and is significantly smaller than the support vessel, so the seakeeping qualities are lower than the support vessel. Larger ship motion is expected than the support vessel and causes communication trouble. In this report, the new active motion compensator and the model experiment with this motion compensator is reported.
{"title":"Motion compensator for acoustic device mounted on Autonomous Surface Vehicle","authors":"Y. Hirakawa, T. Yoda, T. Takayama, T. Hyakudome, T. Nakatani","doi":"10.23919/OCEANS.2015.7401884","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401884","url":null,"abstract":"In recent days, the simultaneous operation of several AUVs is desired to realize widespread exploration in a navigation. As a method to realize the simultaneous operation, introduction the repeater vehicle called ASV (Autonomous Surface Vehicle) is proposed. The task of the ASV is to chase an AUV and to communicate with a support vessel. So, one ASV is needed for one AUV but several ASVs are monitored by one support vessel. The size of the ASV is similar to the AUV and is significantly smaller than the support vessel, so the seakeeping qualities are lower than the support vessel. Larger ship motion is expected than the support vessel and causes communication trouble. In this report, the new active motion compensator and the model experiment with this motion compensator is reported.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130129373","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-01DOI: 10.23919/OCEANS.2015.7404547
F. Miorim, F. Rocha, G. de Tomi
The paper discusses the requirements to design a mobile control center (MCC), which is a remotely operated vehicle (ROV) educational control center that is compact and that can be used in different high sea ROV operations. The intended applications are for research and educational purposes. The need for better-prepared technical professionals is present in the Brazilian offshore oil and gas scenario. In deep-sea operations, where space is scarce and need to be wisely occupied, ROV operators need to have a proper formation and have a widespread awareness of the processes they participate. Using a control center that brings the reality of the operator day-by-day experiences to ROV students will help in the improvement of the skill set of the future ROV operators. A literature survey on the state-of-the-art on the subject was carried out to assess the existing technology and it has shown that there is an opportunity for developing such as concept. Current initiatives reported in the literature include a containerized delivery system with an automated control centers and other features essential to ROV operations. However, our analysis has indicated that this type of solution does not entirely address the requirements for research and educational activities. The mobile control center design should include a generic control center that could be integrated in an agile fashion onto different ROV units from different manufacturers. Besides, it needs to be present in the facilities planed to fit the course, next to the Santos basin, where major in oil engineering is lessoned. By addressing these requirements in this control center and forming techniques and engineers in the same facilities and in with the same attention and teaching method makes them closer and readier to work together in the future.
{"title":"Mobile control center: A new approach to deploy ROV-oriented education and training","authors":"F. Miorim, F. Rocha, G. de Tomi","doi":"10.23919/OCEANS.2015.7404547","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404547","url":null,"abstract":"The paper discusses the requirements to design a mobile control center (MCC), which is a remotely operated vehicle (ROV) educational control center that is compact and that can be used in different high sea ROV operations. The intended applications are for research and educational purposes. The need for better-prepared technical professionals is present in the Brazilian offshore oil and gas scenario. In deep-sea operations, where space is scarce and need to be wisely occupied, ROV operators need to have a proper formation and have a widespread awareness of the processes they participate. Using a control center that brings the reality of the operator day-by-day experiences to ROV students will help in the improvement of the skill set of the future ROV operators. A literature survey on the state-of-the-art on the subject was carried out to assess the existing technology and it has shown that there is an opportunity for developing such as concept. Current initiatives reported in the literature include a containerized delivery system with an automated control centers and other features essential to ROV operations. However, our analysis has indicated that this type of solution does not entirely address the requirements for research and educational activities. The mobile control center design should include a generic control center that could be integrated in an agile fashion onto different ROV units from different manufacturers. Besides, it needs to be present in the facilities planed to fit the course, next to the Santos basin, where major in oil engineering is lessoned. By addressing these requirements in this control center and forming techniques and engineers in the same facilities and in with the same attention and teaching method makes them closer and readier to work together in the future.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"222 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122528326","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-01DOI: 10.23919/OCEANS.2015.7401836
Wei Zhang, Detao Meng, Zhicheng Liang, Ying Li Guo, Jiajia Zhou, Yunfeng Han
During unmanned underwater vehicle (UUV) recovery process, the vision sensor needs to extract and recognize all light sources from guided images. Firstly, Aiming at restoring underwater image without exact depth map, a segmented-linear-mapping approach based on scattering model is put forward. Restoring results indicate that the approach is capable of highlighting subtle details and improving image quality effectively. Then the light source edge and its invariant moments are extracted by Canny edge detection algorithm combined with improved Snake model. At last, a kind of Back Propagation network based on particle swarm optimization algorithm (PSOBP) for UUV recognition is designed, which demonstrates higher recognition rate than traditional BP network.
{"title":"Research on recognition method of UUV vision based on PSO-BP network","authors":"Wei Zhang, Detao Meng, Zhicheng Liang, Ying Li Guo, Jiajia Zhou, Yunfeng Han","doi":"10.23919/OCEANS.2015.7401836","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7401836","url":null,"abstract":"During unmanned underwater vehicle (UUV) recovery process, the vision sensor needs to extract and recognize all light sources from guided images. Firstly, Aiming at restoring underwater image without exact depth map, a segmented-linear-mapping approach based on scattering model is put forward. Restoring results indicate that the approach is capable of highlighting subtle details and improving image quality effectively. Then the light source edge and its invariant moments are extracted by Canny edge detection algorithm combined with improved Snake model. At last, a kind of Back Propagation network based on particle swarm optimization algorithm (PSOBP) for UUV recognition is designed, which demonstrates higher recognition rate than traditional BP network.","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"136 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131254442","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2015-10-01DOI: 10.23919/OCEANS.2015.7404456
G. Seroka, T. Miles, R. Dunk, J. Kohut, S. Glenn, E. Fredj
In July 2014, BOEM issued the NJ Proposed Sale Notice of nearly 344,000 acres designated for offshore wind (OSW) energy development. The BOEM lease auction is expected to take place during the current year. The OSW developer(s) who win the lease(s) will submit their development application to the NJ Board of Public Utilities (NJ BPU). These applications must include a wind resource assessment and economic analysis. One major focus in the NJ BPU OSW rules is that applications “shall account for the coincidence between time of generation for the project and peak electricity demand.” Preliminary data analysis shows two mesoscale processes-coastal upwelling and sea breeze-may have a significant impact on wind generation during peak electricity demand. Tasked by NJ BPU, the Rutgers University Center for Ocean Observing Leadership (RUCOOL) is using the Weather Research and Forecasting (WRF) model to resolve these processes and quantify their impact on the wind resource. The WRF model set-up used is designed specifically for coastal/offshore regions, with three pertinent features for these regions. First, innovative satellite sea surface temperature (SST) composites at 2km resolution are used to resolve coastal upwelling. These composites integrate a) our own declouding algorithm set for the Mid Atlantic Bight to remove cloudy pixels from Advanced Very High Resolution Radiometer (AVHRR) SST scans, and b) coldest pixel composites of the resulting declouded AVHRR SST scans, rather than warmest pixel composites that would effectively remove coastal upwelling. Second, microscale grid spacing (<;1km) is used in WRF to resolve the sea breeze circulation, which can vary at meso- to microscales. Finally, validation of the WRF simulations is performed against coastal/offshore wind monitoring sites with atmospheric heights up to 200m, in order to ensure adequate model performance in coastal/offshore conditions. Three main results will be presented in this paper: (i) Coastal upwelling can produce high wind shear (~8 ms-1 across rotor blade dimensions). These significant shear values could potentially pose engineering challenges and should be considered in wind resource assessments. (ii) Lagrangian Coherent Structure (LCS) methodology can be used to identify key boundaries and fronts within the sea breeze circulation. While the onshore component of the sea breeze is well observed, very little is known about its unobserved offshore component, where OSW turbines will be installed. (iii) Power generation from a hypothetical 3000 MW OSW scenario off NJ was analyzed during three different sea breeze cases (one with strong upwelling, one with weak upwelling, and one without upwelling). Significant variability in power production occurred within each case and across the three sea breeze cases (net capacity factor ranged from 1 to 95%). WRF OSW potential power production data are being ingested by an electricity grid model to evaluate the impact of OSW energy penetration i
{"title":"Sea breeze, coastal upwelling modeling to support offshore wind energy planning and operations","authors":"G. Seroka, T. Miles, R. Dunk, J. Kohut, S. Glenn, E. Fredj","doi":"10.23919/OCEANS.2015.7404456","DOIUrl":"https://doi.org/10.23919/OCEANS.2015.7404456","url":null,"abstract":"In July 2014, BOEM issued the NJ Proposed Sale Notice of nearly 344,000 acres designated for offshore wind (OSW) energy development. The BOEM lease auction is expected to take place during the current year. The OSW developer(s) who win the lease(s) will submit their development application to the NJ Board of Public Utilities (NJ BPU). These applications must include a wind resource assessment and economic analysis. One major focus in the NJ BPU OSW rules is that applications “shall account for the coincidence between time of generation for the project and peak electricity demand.” Preliminary data analysis shows two mesoscale processes-coastal upwelling and sea breeze-may have a significant impact on wind generation during peak electricity demand. Tasked by NJ BPU, the Rutgers University Center for Ocean Observing Leadership (RUCOOL) is using the Weather Research and Forecasting (WRF) model to resolve these processes and quantify their impact on the wind resource. The WRF model set-up used is designed specifically for coastal/offshore regions, with three pertinent features for these regions. First, innovative satellite sea surface temperature (SST) composites at 2km resolution are used to resolve coastal upwelling. These composites integrate a) our own declouding algorithm set for the Mid Atlantic Bight to remove cloudy pixels from Advanced Very High Resolution Radiometer (AVHRR) SST scans, and b) coldest pixel composites of the resulting declouded AVHRR SST scans, rather than warmest pixel composites that would effectively remove coastal upwelling. Second, microscale grid spacing (<;1km) is used in WRF to resolve the sea breeze circulation, which can vary at meso- to microscales. Finally, validation of the WRF simulations is performed against coastal/offshore wind monitoring sites with atmospheric heights up to 200m, in order to ensure adequate model performance in coastal/offshore conditions. Three main results will be presented in this paper: (i) Coastal upwelling can produce high wind shear (~8 ms-1 across rotor blade dimensions). These significant shear values could potentially pose engineering challenges and should be considered in wind resource assessments. (ii) Lagrangian Coherent Structure (LCS) methodology can be used to identify key boundaries and fronts within the sea breeze circulation. While the onshore component of the sea breeze is well observed, very little is known about its unobserved offshore component, where OSW turbines will be installed. (iii) Power generation from a hypothetical 3000 MW OSW scenario off NJ was analyzed during three different sea breeze cases (one with strong upwelling, one with weak upwelling, and one without upwelling). Significant variability in power production occurred within each case and across the three sea breeze cases (net capacity factor ranged from 1 to 95%). WRF OSW potential power production data are being ingested by an electricity grid model to evaluate the impact of OSW energy penetration i","PeriodicalId":403976,"journal":{"name":"OCEANS 2015 - MTS/IEEE Washington","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2015-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127803023","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}