11,019 research outputs found
Pembuatan Sistem Kendali Navigasi Wahana Selam Nir Awak Auv (Autonomous Underwater Vehicle)
Marine observation and research activities require a suitable transportation means that has an ability to bring necessary equipment for data collection and observation into the sea. One of the means that has the ability is AUV (Autonomous Underwater Vehicle), an electric powered underwater vehicle. The vehicle does not require cable connection from the surface and has an ability to move to global positions according to programmable trajectory installed in a microcontroller and other navigation equipment. The control system of the AUV trajectory is programmed in the microcontroller. The navigation equipment consists of integrated sensor. The main sensor used is global positioning sensor, digital compass, pressure sensor, and 3-axys gyroscopes. The main focus of this paper is the design and application of the control system for an underwater survey vehicle that has an ability to bring necessary equipment for observation of coastal area. The vehicle moves from an observation point to another according to GPS assisted programmed data. The control system consists of the thruster system, the depth control system, the positioning system and compass system. The design and algorithm for the control system is proposed
Intelligent Navigation for a Solar Powered Unmanned Underwater Vehicle
In this paper, an intelligent navigation system for
an unmanned underwater vehicle powered by renewable
energy and designed for shadow water inspection in
missions of a long duration is proposed. The system is
composed of an underwater vehicle, which tows a surface
vehicle. The surface vehicle is a small boat with
photovoltaic panels, a methanol fuel cell and
communication equipment, which provides energy and
communication to the underwater vehicle. The underwater
vehicle has sensors to monitor the underwater
environment such as sidescan sonar and a video camera in
a flexible configuration and sensors to measure the
physical and chemical parameters of water quality on
predefined paths for long distances. The underwater
vehicle implements a biologically inspired neural
architecture for autonomous intelligent navigation.
Navigation is carried out by integrating a kinematic
adaptive neuroâcontroller for trajectory tracking and an
obstacle avoidance adaptive neuroâ controller. The
autonomous underwater vehicle is capable of operating
during long periods of observation and monitoring. This
autonomous vehicle is a good tool for observing large areas
of sea, since it operates for long periods of time due to the
contribution of renewable energy. It correlates all sensor
data for time and geodetic position. This vehicle has been
used for monitoring the Mar Menor lagoon.Supported by the Coastal Monitoring
System for the Mar Menor (CMSâ 463.01.08_CLUSTER)
project founded by the Regional Government of Murcia,
by the SICUVA project (Control and Navigation System
for AUV Oceanographic Monitoring Missions. REF:
15357/PI/10) founded by the Seneca Foundation of
Regional Government of Murcia and by the DIVISAMOS
project (Design of an Autonomous Underwater Vehicle
for Inspections and oceanographic missionâUPCT: DPIâ
2009â14744âC03â02) founded by the Spanish Ministry of
Science and Innovation from Spain
Synchronous-Clock, One-Way-Travel-Time Acoustic Navigation for Underwater Vehicles
This paper reports the development and deployment of a synchronous-clock acoustic navigation system suitable for the simultaneous navigation of multiple underwater vehicles. Our navigation system is composed of an acoustic modemâbased communication and navigation system that allows for onboard navigational data to be broadcast as a data packet by a source node and for all passively receiving nodes to be able to decode the data packet to obtain a one-way-travel-time (OWTT) pseudo-range measurement and navigational ephemeris data. The navigation method reported herein uses a surface ship acting as a single moving reference beacon to a fleet of passively listening underwater vehicles. All vehicles within acoustic range are able to concurrently measure their slant range to the reference beacon using the OWTT measurement methodology and additionally receive transmission of reference beacon position using the modem data packet. The advantages of this type of navigation system are that it can (i) concurrently navigate multiple underwater vehicles within the vicinity of the surface ship and (ii) provide a bounded-error XY position measure that is commensurate with conventional moored long-baseline (LBL) navigation systems [i.e., ] but unlike LBL is not geographically restricted to a fixed-beacon network. We present results for two different field experiments using a two-node configuration consisting of a global positioning systemâequipped surface ship acting as a global navigation aid to a Doppler-aided autonomous underwater vehicle. In each experiment, vehicle position was independently corroborated by other standard navigation means. Results for a maximum likelihood sensor fusion framework are reported.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86046/1/reustice-2.pd
Improving Self-Consistency in Underwater Mapping Through Laser-Based Loop Closure (Extended)
Accurate, self-consistent bathymetric maps are needed to monitor changes in
subsea environments and infrastructure. These maps are increasingly collected
by underwater vehicles, and mapping requires an accurate vehicle navigation
solution. Commercial off-the-shelf (COTS) navigation solutions for underwater
vehicles often rely on external acoustic sensors for localization, however
survey-grade acoustic sensors are expensive to deploy and limit the range of
the vehicle. Techniques from the field of simultaneous localization and
mapping, particularly loop closures, can improve the quality of the navigation
solution over dead-reckoning, but are difficult to integrate into COTS
navigation systems. This work presents a method to improve the self-consistency
of bathymetric maps by smoothly integrating loop-closure measurements into the
state estimate produced by a commercial subsea navigation system. Integration
is done using a white-noise-on-acceleration motion prior, without access to raw
sensor measurements or proprietary models. Improvements in map self-consistency
are shown for both simulated and experimental datasets, including a 3D scan of
an underwater shipwreck in Wiarton, Ontario, Canada.Comment: 26 pages, 18 figures. V2 correct Table III x2 parameter values, Table
VIII 'INS' values, and equation A.2
Guidance and Control, for Small AUVs Using DGPS and Doppler Aided Inertial Underwater Navigation
This paper provides an overview of the Naval Postgraduate School ARIES autonomous underwater vehicle and its guidance, navigation and control performance. An attempt is made to highlight its current operational capabilities and provide a description of future enhancements for greater mission utility and flexibility. An overview of the vehicle design along with descriptions of all major hardware components and sensors is given. A major discussion of the implementation of a modular, multi-rate, multi-process software architecture for ARIES autonomous control is provided. The architecture is designed to operate using either a single computer processor or two independent, cooperating processors linked through a network interface for improved load balancing. A dual computer implementation is presented here since each processor assumes different tasks for mission operation. Also included is a section on the underwater navigation method using a real-time extended Kalman filter that fuses all sensor data and computes the real time position, orientation, velocity, etc., of the vehicle. Experimental results for navigational accuracy using a DGPS IMU Doppler aided navigation system are presented with DGPS pop-up maneuvers.Contract N0001402AF0000
A Study on Heading and Attitude Estimation of Underwater Track Vehicle
In this paper, we studied the designing and manufacturing of an underwater track vehicle (UTV) that can be operated in the underwater environment. We designed the electrical and control system for precise operation of the UTV and conduct test operation by using the UTV. We developed an attitude reference system (ARS) that was composed of the ring laser gyro (RLG) sensor, a geomagnetic sensor, and USBL sensor to estimate precise heading and attitude of the UTV. An inertial navigation system (INS) is developed to be combined with the developed ARS. Also, the INS navigation is configured by supplementing the USBL sensor information. We design a controller for a precise trajectory and attitude tracking by installing the ARS on the UTV. In this paper, we used an extended Kalman filter in the INS to estimate the position and attitude of the UTV. The ARS is studied to obtain more precise sensor information in an uncertain environment underwater. Performance tests of the developed INS using the UTV are conducted and the results show that the system has the best performance
A Study on Heading and Attitude Estimation of Underwater Track Vehicle
In this paper, we studied the designing and manufacturing of an underwater track vehicle (UTV) that can be operated in the underwater environment. We designed the electrical and control system for precise operation of the UTV and conduct test operation by using the UTV. We developed an attitude reference system (ARS) that was composed of the ring laser gyro (RLG) sensor, a geomagnetic sensor, and USBL sensor to estimate precise heading and attitude of the UTV. An inertial navigation system (INS) is developed to be combined with the developed ARS. Also, the INS navigation is configured by supplementing the USBL sensor information. We design a controller for a precise trajectory and attitude tracking by installing the ARS on the UTV. In this paper, we used an extended Kalman filter in the INS to estimate the position and attitude of the UTV. The ARS is studied to obtain more precise sensor information in an uncertain environment underwater. Performance tests of the developed INS using the UTV are conducted and the results show that the system has the best performance
An operational concept for correcting navigation drift during sonar surveys of the seafloor
The accumulation of navigation errors (drift) is a problem in many applications of autonomous underwater vehicles (AUVs), particularly during long-duration underwater surveys. Traditional methods for correcting drift require either surfacing of the vehicle for a global navigation satellite systemupdate or use of an independent acoustic positioning system. These methods may not be desirable or possible due to mission constraints. We propose a solution to this problem completely underwater and without the aid of external navigation systems. The approach is based on an operational concept that uses a modified paired-track survey pattern combined with through-the-sensor navigation corrections from a seafloor imaging sonar. We describe the operational concept, derive a model for its performance limits, validate this model, and demonstrate the concept with real experiments at sea. Using this approach, we provide an opportunity to use either coherent or incoherent through-the-sensor positioning corrections for a mission length increase of only the product of the intratrack spacing and the number of track pairs. We show results from a proof-of-principle experiment using data collected by the 300-kHz synthetic aperture sonar of the NATO Centre for Maritime Research and Experimentationâs Minehunting Unmanned underwater vehicle for Shallow water Covert Littoral Expeditions
Experimental Results in Synchronous-Clock One-Way-Travel-Time Acoustic Navigation for Autonomous Underwater Vehicles
This paper reports recent experimental results in the development and deployment of a synchronous-clock acoustic navigation system suitable for the simultaneous navigation of multiple underwater vehicles. The goal of this work is to enable the task of navigating multiple autonomous underwater vehicles (AUVs) over length scales of O(100 km), while maintaining error tolerances commensurate with conventional long-baseline transponder-based navigation systems (i.e., O(1 m)), but without the requisite need for deploying, calibrating, and recovering seafloor anchored acoustic transponders. Our navigation system is comprised of an acoustic modem-based communication/navigation system that allows for onboard navigational data to be broadcast as a data packet by a source node, and for all passively receiving nodes to be able to decode the data packet to obtain a one-way travel time pseudo-range measurement and ephemeris data. We present results for two different field experiments using a two-node configuration consisting of a global positioning system (GPS) equipped surface ship acting as a global navigation aid to a Doppler-aided AUV. In each experiment, vehicle position was independently corroborated by other standard navigation means. Initial results for a maximum-likelihood sensor fusion framework are reported.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/86032/1/reustice-20.pd
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