Marine Robotic System of Self Organizing, Logically Linked Physical Nodes (MORPH)

The MORPH project advances the novel concept of an underwater robotic system composed of a number of spatially separated mobile robot-modules, carrying distinct and yet complementary resources. Instead of being physically coupled, the modules are connected via virtual links that rely on the flow of information among them, i. e. inter-module interactions are allowed by underwater communication networks at distant and close ranges and supported by visual perception at very close range. The MORPH supra-vehicle (MSV) is thus in sharp contrast to classical monolithic vehicles or even cooperative groups of marine vehicles that operate safely away from each other. These lack the capability of mutual support and multi-sensor interaction.Without rigid links, the MSV can reconfigure itself and adapt in response to the shape of the terrain. This capability provides the foundation for efficient methods to map the underwater environment with great accuracy especially in situations that defy existing technology: namely, underwater surveys over rugged terrain and structures with full 3D complexity. This includes walls with a negative slope, where precise localization of a single vehicle is not possible.The possible applications of the MSV cover a wide range of scientific and commercial areas such as monitoring of cold water coral reefs, oil and gas pipeline inspection, or harbor and dam protection. The common characteristic of these areas is the need for operating multiple, complementary instruments at very close range to unstructured underwater terrain while accomplishing proper geo-referencing at the same time.The MORPH concept requires qualitatively new behaviours such as adaptive sensor placement for perception and navigation, as well as environmental modeling in complex environments. On site view planning will lead to a solution well beyond the operational state of the art for underwater cliff surveys and other similar missions. A final demonstration on a vertical cliff, unfeasible automatically with today’s technology, will validate the efficacy of the methods developed.

Jacobs Robotics is among others responsible for 3D Underwater Mapping in the project. We have for example developed a underwater stereo camera and new methods to generate 3D maps from the data by novel registration algorithms. Our group has for example successfully tested this system in the waters off the Portuguese Azores islands in summer 2012 in cooperation with the University of the Azores (UAC).

Project Partners

• ATLAS Elektronik GMBH
• IMAR – Instituto do Mar
• Jacobs University
• TU Ilmenau
• Universitat de Girona
• Centre for Maritime Research and Experimentation (CMRE)
• Consiglio Nazionale delle Ricerche (CNR)
• Institut Francais de Recherche pour l’exploitation de la mer (Ifremer)
• Instituto Superior Tecnico (IST)

Publications

The following publications by Constructor Robotics have appeared in the context of the project.

• [1] J. Kalwa, A. Pascoal, P. Ridao, A. Birk, M. Eichhorn, and L. Brignone, “The European RnD-Project MORPH: Marine robotic systems of self-organizing, logically linked physical nodes,” in IFAC Workshop on Navigation, Guidance and Control of Underwater Vehicles (NGCUV), Porto, Portugal, 2012. https://doi.org/10.3182/20120410-3-PT-4028.00058 [Preprint]
• [2] M. Pfingsthorn, A. Birk, and H. B{\”u}low, “Uncertainty Estimation for a 6-DoF Spectral Registration method as basis for Sonar-based Underwater 3D SLAM,” in International Conference on Robotics and Automation (ICRA), Saint Paul, Minnesota, 2012. https://doi.org/10.1109/ICRA.2012.6224731 [Preprint]
• [3] R. Rathnam and A. Birk, “Cooperative 3D Exploration under Communication Constraints,” in IFAC Workshop on Navigation, Guidance and Control of Underwater Vehicles (NGCUV), Porto, Portugal, 2012. https://doi.org/10.3182/20120410-3-PT-4028.00016 [Preprint]
• [4] H. B{\”u}low and A. Birk, “Spectral 6-DOF Registration of Noisy 3D Range Data with Partial Overlap,” IEEE Transactions on Pattern Analysis and Machine Intelligence (PAMI), vol. 35, pp. 954-969, 2013. https://doi.org/10.1109/TPAMI.2012.173 [Preprint]
• [5] H. B{\”u}low, I. Sokolovski, M. Pfingsthorn, and A. Birk, “Underwater Stereo Data Acquisition and 3D Registration with a Spectral Method,” in IEEE Oceans, Bergen, Norway, 2013. https://doi.org/10.1109/OCEANS-Bergen.2013.6608115 [Preprint]
• [6] K. Pathak, M. Pfingsthorn, H. B{\”u}low, and A. Birk, “Robust Estimation of Camera-Tilt for iFMI based Photo-Mapping using a Calibrated Monocular Camera,” in IEEE International Conference on Robotics and Automation (ICRA), Karlsruhe, Germany, 2013. https://doi.org/10.1109/ICRA.2013.6631307 [Preprint]
• [7] M. Pfingsthorn, H. B{\”u}low, A. Birk, F. Ferreira, G. Veruggio, M. Caccia, and G. Bruzzone, “Large-Scale Mosaicking with Spectral Registration based Simultaneous Localization and Mapping (iFMI-SLAM) in the Ligurian Sea,” in IEEE Oceans, Bergen, Norway, 2013. https://doi.org/10.1109/OCEANS-Bergen.2013.6608146 [Preprint]
• [8] R. Rathnam and A. Birk, “Initial Results of Cooperative AUV Exploration in a High-Fidelity Simulation using Real-World Data from Monte da Guia, Azores,” in IEEE Oceans, Bergen, Norway, 2013. https://doi.org/10.1109/OCEANS-Bergen.2013.6608147 [Preprint]
• [9] M. Pfingsthorn, A. Birk, F. Ferreira, G. Veruggio, M. Caccia, and G. Bruzzone, “Large-Scale Image Mosaicking using Multimodal Hyperedge Constraints from Multiple Registration Methods within the Generalized Graph SLAM Framework,” in IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Chicago, USA, 2014. https://doi.org/10.1109/IROS.2014.6943209 [Preprint]
• [10] I. Enchev, M. Pfingsthorn, T. Luczynski, I. Sokolovski, A. Birk, and D. Tietjen, “Underwater Place Recognition in Noisy Stereo Data using Fab-Map with a Multimodal Vocabulary from 2D Texture and 3D Surface Descriptors,” in IEEE Oceans, Genoa, Italy, 2015. https://doi.org/10.1109/OCEANS-Genova.2015.7271561 [Preprint]
• [11] J. Kalwa, A. M. Pascoal, P. Ridao, T. Glotzbach, L. Brignone, M. Bibuli, J. Alves, A. Birk, and M. C. Silva, “EU Project MORPH: Current Status after 3 Years of Cooperation under and above Water,” in IFAC Workshop on Navigation, Guidance and Control of Underwater Vehicles (NGCUV), 2015. https://doi.org/10.1016/j.ifacol.2015.06.019 [Preprint]
• [12] R. Rathnam and A. Birk, “Multi-Robot Exploration with AUVs on Cliffs and other 3D Structures with a Predominant Orientation,” in IEEE Oceans, Genoa, Italy, 2015. https://doi.org/10.1109/OCEANS-Genova.2015.7271563 [Preprint]
• [13] A. G. Chavez, J. Fontes, P. Afonso, M. Pfingsthorn, and A. Birk, “Automated Species Counting using a Hierarchical Classification Approach with Haar Cascades and Multi-Descriptor Random Forests,” in IEEE Oceans, Shanghai, China, 2016. https://doi.org/10.1109/OCEANSAP.2016.7485544 [Preprint]
• [14] A. G. Chavez, M. Pfingsthorn, R. Rathnam, and A. Birk, “Visual Speed Adaptation for Improved Sensor Coverage in a Multi-Vehicle Survey Mission,” in IEEE Oceans, Shanghai, China, 2016. https://doi.org/10.1109/OCEANSAP.2016.7485710 [Preprint]
• [15] M. Pfingsthorn and A. Birk, “Generalized Graph SLAM: Solving Local and Global Ambiguities through Multimodal and Hyperedge Constraints,” International Journal of Robotics Research (IJRR), vol. 35, pp. 601-630, 2016. https://doi.org/10.1177/0278364915585395 [Preprint]
• [16] M. Pfingsthorn, R. Rathnam, T. Luczynski, and A. Birk, “Full 3D Navigation Correction using Low Frequency Visual Tracking with a Stereo Camera,” in IEEE Oceans, Shanghai, China, 2016. https://doi.org/10.1109/OCEANSAP.2016.7485520 [Preprint]