@conference {235, title = {Multi-view underwater 3D reconstruction using a stripe laser light and an eye-in-hand camera}, booktitle = {Oceans{\textquoteright}15 MTS/IEEE Genova}, year = {2015}, month = {09/2015}, publisher = {IEEE}, organization = {IEEE}, address = {Genova (Italy)}, abstract = {

Autonomous manipulation in unestructured underwater scenarios is a high challenging skill that has been poorly studied and is becoming more and more important in the last years. One of the main problems regarding the autonomous manipulation, is to find out the characteristics of the object which is going to be manipulated. This paper presents a new approach to obtain an accurate 3D reconstruction of this object. This approach consists in attaching a laser stripe emitter and a camera in the forearm of a robotic arm. Moving the arm, the laser scans the scene where the object is and, at the same time, the camera records the scan. Thanks to the arm and the position of the camera, the scene can be reconstructed from different views and from a position close to the object. The recorded images are processed to obtain the 3D position of the part of the scene projected by the laser. Before the intervention, a process of calibration is needed to calculate the relationship between each part of the system. Furthemore, in order to reduce the time of processing of the images recorded during the scan, an optimization algorithm is presented which consists in discarding, before the processing, the pixels of the image which do not contain relevant information. The approach herein presented and the optimization algorithm are tested using an underwater simulator.

}, keywords = {3D reconstruction, autonomous grasping, Laser-Camera Calibration, Optimization Algorithm, Underwater Laser Scanning}, isbn = {978-1-4799-8736-8}, doi = {10.1109/OCEANS-Genova.2015.7271497}, url = {https://doi.org/10.1109/OCEANS-Genova.2015.7271497}, author = {Pe{\~n}alver, Antonio and Fern{\'a}ndez, Jos{\'e} Javier and Sales, Jorge and Sanz, Pedro J.} } @conference {180, title = {Semi-autonomous grasping approach of unknown objects in underwater environments combining structured light and a virtual simulation environment}, booktitle = {5TH MARTECH International Workshop On Marine Technology}, year = {2013}, month = {10/2013}, address = {Girnoa (Spain)}, abstract = {

Many scientific and industrial works that take place
underwater are increasingly demanding for technology to allow
their autonomous execution. Autonomous grasping of unknown
objects by a robotic arm is a task that is being highly studied by
researchers in the last years. This is a really difficult task in itself,
but the problem is bigger if the grasp is done in underwater
environments, where the sensors that can be installed in the arm,
decrease their performance drastically. This paper describes an
approach for semi-autonomous grasping of underwater unknown
objects using a robotic arm. To achieve this purpose, a scan of the
scene is performed using a structured laser beam attached to the
forearm of the manipulator. At the same time, a digital video
camera is used to capture the scene. The laser stripes are
triangulated to obtain a 3D point cloud. The entire process is
shown inside an underwater simulator, acting in this case as a
virtual representation of the real environment. This virtual
representation allows the user to specify the grasp, to see how the
grasp will be executed, and to monitor the final process in real
time. To validate the good performance of the proposed
approach, several grasping experiments with two different objects
have been performed in water tank conditions with a real I-AUV
system.

}, keywords = {3D reconstruction, Intervention AUV, semiautonomous grasping, underwater recovery}, isbn = {978-84-616-5764-3}, author = {Pe{\~n}alver, Antonio and Prats, Mario and Fern{\'a}ndez, Jos{\'e} Javier and Sales, J.} }