Intervention AUV

About: Intervention AUV is a research topic. Over the lifetime, 980 publications have been published within this topic receiving 14130 citations.

A Robust Vision-Based Hover Control for ROV

Abstract: The main field of application for small- and middle-class ROVs is the inspection of underwater structures or other objects of interest. Approaching such an object, one would want to hold a steady position in front of the object to study it in detail without having to concentrate on the control of the vehicle. This kind of "hover control" could be implemented by using an inertial measurement unit (IMU), but most of the small-and middle-class ROVs do not have one. Furthermore, even the best IMUs tend to drift. On this account our approach, which is presented in this paper, uses video data to estimate the movements of the vehicle and uses these data to keep the vehicle hovering in front of a particular structure. The used vision algorithms are aimed at real world applications and are robust enough to handle various light and visibility conditions.

Hybrid robot crawler / flyer for use in underwater archaeology

Abstract: Remotely operated crawlers are specialized vehicles that allow for underwater intervention by staying in direct contact with the seafloor. The crawler offers a very stable platform for manipulating objects or for taking measurements. Additionally, crawlers lend themselves to long-term work. Crawlers are already well established platforms for various environments. For example, planetary rovers have successfully proven themselves in missions to the moon and mars. At Florida Institute of Technology a hybrid remotely operated crawler has been developed for archaeological and scientific activities within coastal regions of the ocean. This hybrid vehicle combines a standard 40-cm high, 53-cm wide, 71-cm long remotely operated vehicle (ROV) flyer with a 1.0-m high, 1.52-m wide, 2.8-m long remotely operated vehicle crawler for multiple research activities such as underwater archaeology documentation and artifact removal. Named the RG-III, the hybrid vehicle is currently designed to operate in depths down to 100-m. The vehicle is controlled by a remote control cable from the beach or boat and is equipped with video, still cameras and robotic grippers. Capable of carrying most environmental data gathering instruments the crawler is also able to “fly” when necessary by filling flotation bladders and using its four mounted thrusters. This capability allows the vehicle to jump from one side of a shipwreck to another or to fly over sensitive regions such as reefs. The ROV-flyer piggy-backs on the ROV-crawler and can separate to become an “eye-in-the-sky” to observe from above the activities of the ROV-crawler.

The general design of a seafloor surveying AUV system

Abstract: Owing to the exceptional ability of obtaining maximum data quality by bringing advanced payload sensors close to the seafloor, AUVs have been widely applied to seafloor survey task in recent years. Tianjin University developed a seafloor mapping AUV in 2010. In this paper, the energy consumption and endurance of the seafloor mapping AUV are predicted. To optimize the maneuverability at the early design stage, the hydrodynamic characteristics of the vehicle are calculated and evaluated. A propeller-gear-motor combination thruster is developed to ensure maneuverability and realize high resolution trajectory tracing at a low speed. An aided inertial navigation system integrating a number of surface and subsea navigation sensors is mounted on the vehicle to achieve better surveying data quality. Several trials were conducted and the general design of the whole system is verified.

Development of a Hovering-Type Intelligent Autonomous Underwater Vehicle, P-SURO

Abstract: P-SURO(PIRO-Smart Underwater RObot) is a hovering-type test-bed autonomous underwater vehicle (AUV) for developing various underwater core technologies (Li et al., 2010). Compared to the relatively mature torpedo-type AUV technologies (Prestero, 2001; Marthiniussen et al., 2004), few commercial hovering-type AUVs have been presented so far. This is partly because some of underwater missions of hovering-type AUV can be carried out through ROV (Remotely Operated Vehicle) system. But the most important reason is of less mature core technologies for hovering-type AUVs. To carry out its underwater task, hovering-type AUV may need capable of accurate underwater localization, obstacle avoidance, flexible manoeuvrability, and so on. On the other hand, because of limitation of present underwater communication bandwidth, high autonomy of an AUV has become one of basic function for hovering AUVs (Li et al., 2010). As a test-bed AUV, P-SURO has been constructed to develop various underwater core technologies, such as underwater vision, SLAM, and vehicle guidance & control. There are four thrusters mounted to steer the vehicle's underwater motion: two vertical thrusters for up/down in the vertical plane, and 3DOF horizontal motion is controlled by two horizontal ones, see Fig. 1. Three communication channels are designed between the vehicle and the surface control unit. Ethernet cable is used in the early steps of development and program/file upload and download. On the surface, RF channel is used to exchange information and user commands, while acoustic channel (ATM: Acoustic Telemetry Modem) is used in the under water. A colour camera is mounted at the vehicle's nose. And three range sonar, each of forward, backward and downward, are designed to assist vehicle's navigation as well as obstacle avoidance and SLAM. An AHRS combined with 1axis Gyro, 1-axis accelerometer, depth sensor consist of vehicle's navigation system. In this chapter, we report the details of to date development of the vehicle, including SLAM, obstacle detection/path planning, and some of vehicle control algorithms. The remainder of this chapter is organized as follows. In Section II, we introduce the vehicle's general specifications and some of its features. Underwater vision for P-SURO AUV is discussed in Section III, and the SLAM algorithm in the basin environment is presented in Section IV. In Section V, we discuss some of control issues for P-SURO AUV. Finally in Section VI, we make a brief summary of the report and some future research issues are also discussed.