Exploring marine environments poses unique challenges that require specialized technological solutions. For example, navigating in deep waters, amid strong currents, and with limited visibility, often requires creative and overengineered strategies.

The primary focus of the ORUS laboratory is on the advancement of ocean robotics for ocean research.

We pursue research in essential areas, including enhanced navigation, guidance, autonomous mission control for single and multiple vehicles, multibeam sonar-based control, machine learning-enhanced decision making, and sophisticated cooperative control for fleets of ocean vehicles.

Our research applies a wide range of rigorous and structured mathematical tools to a variety of autonomous ocean vehicles, each streamlined for a different task. This currently includes the ORVIS Autonomous Underwater Vehicle (AUV) and the DELMAC Autonomous Surface Vehicle (ASV), the latter equipped with an extensive sensor suite for strategic surface-level missions, as well as for support and coordination in missions involving underwater platforms.

Our fleet of vehicles will also include, in due course: Intervention Autonomous Underwater Vehicles (I-AUVs) equipped with advanced navigation and manipulation capabilities; highly efficient torpedo-like vehicles for detailed ocean floor mapping; and gliders for long-duration oceanographic data collection.

We harness all these different technologies for a variety of critical applications, for example, comprehensive studies of underwater ecosystems, creation of marine habitat maps, collection and analysis of environmental data, accurate pollution assessments, identification and mitigation of environmental hazards, exploration and study of submerged historical sites with least obtrusive gear and techniques, etc.

At the ORUS laboratory, we believe in unleashing the untapped potential of ocean robotics to address the multifaceted challenges and opportunities presented by marine environments.

The autonomous vehicles at ORUS Lab

DELMAC Autonomous Surface Vehicle

Autonomous marine craft are steadily playing an ever-increasing role in the study of the ocean. Among these, autonomous surface vehicles (ASVs) are becoming quite appealing for operations in shallow waters. Equipped with advanced navigation and control systems, sophisticated acoustic sensors, and systems for mission programming and execution, they afford end-users the tools that are needed to automatically map the seabed at an unprecedented scale without constant supervision of human operators. ASVs also play an important role in the study of new approaches for underwater exploration and mapping, in that they allow assessing proper methodologies for the electrical/mechanical integration of new sensors. In the scope of the ORUS Lab of the University of Macau, we foresee the use of advanced acoustic sensor suites to accurately map shallow water regions. An important step in this direction has been the myriad of tests in the lakes of the University of Macau using the DELMAC ASV in shallow water operations, vital for assessing the performance of our navigation and control algorithms.

The DELMAC craft is a small boat 1.8 m long and 0.8 m wide, weighing approximately 30 kg. For propulsion, the vehicle is equipped with two bladed propellers driven by electrical motors. The maximum rated speed of the vehicle with respect to the water is 5 knots. The DELMAC is equipped with on-board resident systems for navigation, guidance and control, as well as mission control. Navigation is achieved by integrating motion sensor data obtained from an attitude reference unit and a DGPS (Differential Global Positioning System) or, for higher accuracy, a RTKGPS (Real Time Kinematics Global Positioning System). Transmissions between the ASV and its support vessel – or a control centre installed on-shore – are achieved via an Ethernet radio link capable of long-distance communication, up to 10 km, at high data rates. Future plans include using the DELMAC for bathymetric operations and sea floor characterization resorting to sensor suites that include sonar profiler or small size multibeam sonar.

ORVIS Autonomous Underwater Vehicle

ORVIS is an AUV intended to perform shallow water interventions in Macau waters for accurate shallow water bathymetry, inspection of underwater structures, studies of marine biodiversity, assessment of the human impact on the marine environment, detection and localization of toxic spills, to name just a few. In view of stringent practical requirements in some complex underwater missions, where current levels of autonomy are still inadequate to ensure vehicle safety and correct operation, ORVIS can also be used as a remotely operated vehicle (ROV).

The ORVIS AUV prototype was fully developed, from concept and design to assembling and programming, at the University of Macau. The vehicle is equipped with algorithms for high accuracy bathymetry and seabed mapping based on affordable multibeam imaging and doppler velocity log sonars; novel nonlinear trajectory tracking and path following controllers with bottom following and obstacle avoidance capabilities that enables it to perform accurate bathymetry with full seabed coverage of the target areas in the presence of unexpected static or even dynamic obstacles; and fault detection and isolation tools.

The ORVIS AUV sensor suite includes a Microstrain Inertial Measurement Unit, a GPS receiver with RTK corrections, an Oculus 1200d Multibeam Imaging sonar, a WaterLinked A50 Doppler Velocity Log, a WaterLinked Acoustic Modem, a PicoBoard52R Single Board Computer, and a GPU board NVIDIA Jetson Nano, all integrated in Robotic Operation System (ROS) over Linux. It is powered by two sets of lithium polymer batteries, allowing the vehicle to carry out missions lasting up to 4 hours.

The design and construction of the ORVIS AUV prototype was carried out by members of the ORUS team with solid experience in the development of ocean robotic vehicles. In particular, the design of the mechanical hull and propulsion system took into consideration the constraints imposed by the desired vehicle’s autonomy and hydrodynamic performance, space for the equipment selected, transportability and operationality. The shape and weight distribution of the vehicle was obtained in function of the required open loop stability and closed loop manoeuvrability, for the types of envisioned missions. Furthermore, particular care was exercised in the analysis of the impact of the metacentric height on the vehicle pitch and roll dynamics which are determinant in the vehicle behaviour while performing bottom tracking in bathymetry missions.