This study considers the data processing for acoustic cameras and achieves the generation of high-quality acoustic panoramas through image mosaicking. Thanks to high-resolution imaging, acoustic cameras are increasingly popular in ocean engineering. However, their narrow detection field of view makes it challenging to intuitively perceive marine environments. Generating large panoramas through mosaicking is a good way to solve this problem. Due to limitations such as low resolution, low signal-to-noise ratio, weak textures, and nonlinear distortions in acoustic images, most classic mosaicking pipelines do not perform well. This study proposes an adaptive mosaicking framework for acoustic cameras that integrates image denoising, feature matching, and mosaicking modules. It can generate large-area panoramas from overlapping acoustic camera images without any assumptions regarding the scenes. The overall process consists of three main steps: first, introduce a self-supervised denoising strategy to preprocess acoustic images to effectively remove complex noise; second, use a detector-free paradigm to achieve feature matching between adjacent acoustic images. This paradigm matches dense pixels in the high-level structure of images rather than relying on isolated geometric features, addressing the matching challenges in weak-texture areas. Third, design a mosaicking approach based on matching results to generate acoustic panoramas. This framework has been verified experimentally, and the results show that it canrobustly and effectively mosaic acoustic images, providing a novel reference and solution for underwater structures inspection in complex marine environments.
{"title":"Acoustic Camera-Based Adaptive Mosaicking Framework for Underwater Structures Inspection in Complex Marine Environments","authors":"Xiaoteng Zhou;Katsunori Mizuno;Yilong Zhang;Kenichiro Tsutsumi;Hideki Sugimoto","doi":"10.1109/JOE.2024.3423868","DOIUrl":"10.1109/JOE.2024.3423868","url":null,"abstract":"This study considers the data processing for acoustic cameras and achieves the generation of high-quality acoustic panoramas through image mosaicking. Thanks to high-resolution imaging, acoustic cameras are increasingly popular in ocean engineering. However, their narrow detection field of view makes it challenging to intuitively perceive marine environments. Generating large panoramas through mosaicking is a good way to solve this problem. Due to limitations such as low resolution, low signal-to-noise ratio, weak textures, and nonlinear distortions in acoustic images, most classic mosaicking pipelines do not perform well. This study proposes an adaptive mosaicking framework for acoustic cameras that integrates image denoising, feature matching, and mosaicking modules. It can generate large-area panoramas from overlapping acoustic camera images without any assumptions regarding the scenes. The overall process consists of three main steps: first, introduce a self-supervised denoising strategy to preprocess acoustic images to effectively remove complex noise; second, use a detector-free paradigm to achieve feature matching between adjacent acoustic images. This paradigm matches dense pixels in the high-level structure of images rather than relying on isolated geometric features, addressing the matching challenges in weak-texture areas. Third, design a mosaicking approach based on matching results to generate acoustic panoramas. This framework has been verified experimentally, and the results show that it canrobustly and effectively mosaic acoustic images, providing a novel reference and solution for underwater structures inspection in complex marine environments.","PeriodicalId":13191,"journal":{"name":"IEEE Journal of Oceanic Engineering","volume":"49 4","pages":"1549-1573"},"PeriodicalIF":3.8,"publicationDate":"2024-08-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142200200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-20DOI: 10.1109/JOE.2024.3423869
Karl D. von Ellenrieder;Marco Camurri
The use of automatic safety-critical control for uncrewed surface vessel (USV) survey, inspection and intervention can provide a computationally lightweight controller which guarantees that a minimum safe standoff distance to a target of interest is always maintained. We propose a trajectory tracking safety-critical controller for the closest safe approach of an underactuated USV with nonholonomic dynamic (acceleration) motion constraints to a target. A backstepping-based control law is designed using a relaxed control barrier function and an analytical convex optimization method. The stability of the controller is proven. Simulations of a USV approaching both stationary and moving targets are used to demonstrate implementation of the method. The performance of the proposed controller is compared with that of a nonlinear model predictive control (MPC) controller in simulation. The simulation results demonstrate that, while the tracking error of the proposed controller is higher than that of an MPC controller, it requires lower computational resources, suggesting it is a good candidate for use on small USVs with low computational power.
{"title":"Relaxed Control Barrier Function Based Control for Closest Approach by Underactuated USVs","authors":"Karl D. von Ellenrieder;Marco Camurri","doi":"10.1109/JOE.2024.3423869","DOIUrl":"https://doi.org/10.1109/JOE.2024.3423869","url":null,"abstract":"The use of automatic safety-critical control for uncrewed surface vessel (USV) survey, inspection and intervention can provide a computationally lightweight controller which guarantees that a minimum safe standoff distance to a target of interest is always maintained. We propose a trajectory tracking safety-critical controller for the closest safe approach of an underactuated USV with nonholonomic dynamic (acceleration) motion constraints to a target. A backstepping-based control law is designed using a relaxed control barrier function and an analytical convex optimization method. The stability of the controller is proven. Simulations of a USV approaching both stationary and moving targets are used to demonstrate implementation of the method. The performance of the proposed controller is compared with that of a nonlinear model predictive control (MPC) controller in simulation. The simulation results demonstrate that, while the tracking error of the proposed controller is higher than that of an MPC controller, it requires lower computational resources, suggesting it is a good candidate for use on small USVs with low computational power.","PeriodicalId":13191,"journal":{"name":"IEEE Journal of Oceanic Engineering","volume":"49 4","pages":"1301-1321"},"PeriodicalIF":3.8,"publicationDate":"2024-08-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10639539","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142438530","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-16DOI: 10.1109/JOE.2024.3415753
Andrea Trucco
The study of the impact on the marine ecosystem of an offshore wind farm benefits from the knowledge of the underwater noise observed at a single turbine, as the wind speed varies. The calculation of the noise spectral average at a given wind speed requires many recordings, each acquired in a limited time interval: an extremely time-consuming process. This study investigated how to approach the spectral average using only very few noise recordings for each wind speed, leveraging supervised and unsupervised machine learning techniques. Three different prediction methods, based on mean and interpolation, principal component analysis (PCA), and nonnegative matrix factorization, in combination with four techniques for coefficient estimation as the wind varies, are tested. Prediction based on principal component analysis, combined with Gaussian process regression, outperforms other methods in all three case studies considered. The latter, in addition to the problem described above, include the prediction of the noise spectrum: at wind speeds where no noise recordings are available, and using a few recordings acquired at another (nominally identical) wind turbine.
{"title":"Predicting Underwater Noise Spectra Dominated by Wind Turbine Contributions","authors":"Andrea Trucco","doi":"10.1109/JOE.2024.3415753","DOIUrl":"10.1109/JOE.2024.3415753","url":null,"abstract":"The study of the impact on the marine ecosystem of an offshore wind farm benefits from the knowledge of the underwater noise observed at a single turbine, as the wind speed varies. The calculation of the noise spectral average at a given wind speed requires many recordings, each acquired in a limited time interval: an extremely time-consuming process. This study investigated how to approach the spectral average using only very few noise recordings for each wind speed, leveraging supervised and unsupervised machine learning techniques. Three different prediction methods, based on mean and interpolation, principal component analysis (PCA), and nonnegative matrix factorization, in combination with four techniques for coefficient estimation as the wind varies, are tested. Prediction based on principal component analysis, combined with Gaussian process regression, outperforms other methods in all three case studies considered. The latter, in addition to the problem described above, include the prediction of the noise spectrum: at wind speeds where no noise recordings are available, and using a few recordings acquired at another (nominally identical) wind turbine.","PeriodicalId":13191,"journal":{"name":"IEEE Journal of Oceanic Engineering","volume":"49 4","pages":"1675-1694"},"PeriodicalIF":3.8,"publicationDate":"2024-08-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://ieeexplore.ieee.org/stamp/stamp.jsp?tp=&arnumber=10638433","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142200204","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2024-08-16DOI: 10.1109/JOE.2024.3412227
Worakrit Thida;Roberto Li Voti;Sorasak Danworaphong
This study explored the use of top-view movies of propagating gravity water waves to reconstruct the underwater bed profile of shallow water bodies. Water waves of 2.8 and 3.1 Hz were generated by a microcontroller-driven flat flap in a wave flume of dimensions 0.48 × 1.80 × 0.40 m $^{3}$