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This paper presents an intelligent decision algorithm and an on-board architecture designed to enable an autonomous underwater vehicle (AUV) to carry out a survey mission autonomously. The connotation of global model in decision algorithm is analyzed, including environment information, mission information and Self-states of AUV. The survey mission of multi-objective operation areas in an unsafe zone...
The random drift of fiber-optic gyroscope (FOG) and zero bias of accelerometer are the main factors for the precision of FOG strapdown system, and theoretical study shows their negative influences on the system can be greatly reduced by the azimuth rotation method. However, the results of azimuth rotation experiments using the medium precision FOG strapdown system developed by our lab and the high...
We are developing onboard planning and execution technologies to provide robust and opportunistic mission operations for a future Titan Aerobot. Aerobot have the potential for collecting a vast amount of high priority science data. However, to be effective, an aerobot must address several challenges including communication constraints, extended periods without contact with Earth, uncerttain and changing...
In this paper, we propose a maritime underwater navigation system (MUNS) for unmanned underwater vehicles (UUVs). The proposed MUNS has a hierarchical architecture comprising of a wide area planner (WAP) and a local area planner (LAP). MUNS is intended to be a plug-and-play module to provide obstacle avoidance and path planning capabilities to existing UUV platforms thereby expanding operational capabilities...
In this research, we propose a unique multi-planar LIDAR and computer vision calibration algorithm. This method only requires the camera and LIDAR to observe a planar pattern at different positions and orientations. Geometric constraints of the dasiaviewspsila from the LIDAR and camera images are resolved as the coordinate transformation coefficients. The proposed approach consists of two stages:...
The goal of map matching methods is to compute an accurate position of a vehicle from an initial estimated position using a digital road network data. In this paper, a new map matching method based on Dempster-Shafer theory and interval analysis is presented. The core idea of this method is the use of Dempster-Shafer theory for modeling partial information on model and measurement uncertainties and...
Tunnels are an increasing problem for securing the borders. Due to hazards inherent in assessing these tunnels, robotic reconnaissance would play an important role in gathering vital information regarding tunnel use and closure logistics. Since conventional robotics platforms do not meet the threat needs, the unmanned tunnel exploitation (UTE) research used numerical simulation and experimentation...
The real-time simulation environment is developed for the design and test of the distributed controller for the TESTBED autonomous underwater vehicle. The vehicle dynamics is real-timely simulated in an industrial control computer and all the motion sensors and actuators external to the distributed controller is modeled with proper interfaces, allowing complete pseudo-mission simulation and analysis...
Recently there has been increasing research on the development of autonomous flying vehicles.Whereas most of the proposed approaches are suitable for outdoor operation, only a few techniques have been designed for indoor environments. In this paper we present a general system consisting of sensors and algorithms which enables a small sized flying vehicle to operate indoors. This is done by adapting...
This paper describes the system architecture and core algorithms for a quadrotor helicopter that uses vision data to navigate an unknown, indoor, GPS-denied environment. Without external sensing, an estimation system that relies only on integrating inertial data will have rapidly drifting position estimates. Micro aerial vehicles (MAVs) are stringently weight-constrained, leaving little margin for...
The last decade has witnessed the establishment of image processing as a viable means of aiding underwater navigation. However, many such systems are only implemented in pre-processing and offline due to their excessive computational demands. Real-time techniques often require special purpose hardware or impose limitations on the system to obtain real-time performance at the expense of accuracy. The...
As unmanned marine vehicles rapidly establish themselves as powerful and reliable tools in an ever increasing number of tasks, the focus of research has shifted towards simultaneous operation of coordinated fleets of vehicles. The GREX project joins this development effort with a comprehensive and ambitious development plan. This paper gives account of the first sea trials experience involving a fleet...
On 31st January 2009, two numbers: ldquorange and bearingrdquo flashing up on a laptop screen, indicated that Autosub3 had returned from its last mission beneath the Pine Island Glacier (PIG) Ice Shelf in the Western Antarctic. The Autosub technical team from NOCS, Southampton, onboard the US ice breaker Nathanial B Palmer breathed a collective sigh of relief. Any significant technical failure would...
This paper will present new approaches regarding component and system design for underwater vehicles. The test vessel DNS Pegel was designed to test pressure tolerant devices for permanent submerged applications. It was built during the project ldquoPressure tolerant systems for permanent submerged applicationsrdquo. The vehicle is equipped with a minimal navigation system and a data logging system...
Conclusion from previous I-AUV projects and separate research in navigation and docking were consolidated to form a guideline for autonomous underwater docking. The example of docking on intervention panel was chosen to show how the standard can be expanded to improve on the key factors: navigational precision, reliability and mechanics. Particular results are shown for localization techniques to...
This paper discusses estimation of relative positions of a group of autonomous underwater or surface vehicles. The solution to this problem is crucial for performing cooperated missions. It is show that the relative positioning problem is solvable when dead reckoning data is combined with mutual range data provided by some additional device, e.g. by acoustic telemetry. This data has to be distributed...
Intelligent transportation systems (ITS) are the mainstream of the development of next-generation technologies. The project of Human-centered technology (HT)-ITS in Taiwan has launched R&D researches in driver assistance and safety warning systems. This paper demonstrates a part result that a multi-sensors integrated system to achieve the purpose of the vehicle navigation and safety warning assistance...
Intelligent vehicle is the vehicle which has ability to drive itself autonomously and purposefully. The vehicle is expected to facilitate the people who cannot drive. Some modules of the vehicle; steering control, for instances, can assist the driver to make the driver drive more comfortable and safely. This paper proposes an autonomous navigation and control algorithm which is capable to travel around...
Inertial measurement unit (IMU), consisted of three mutually-perpendicular ring laser gyros (RLG) and three accelerometers, is an important part of RLG-based strap-down inertial navigation systems (SINS). RLG provides measurement of change in vehicle attitude or its turn rate with respect to inertial space. Accelerometer provides measurement of specific force. These measurements provided by gyros...
This paper present the theoretical development of a complete navigation problem of a non-holonomic mobile robot by using sonar sensors. To solve this problem, a new method to compute a fuzzy perception of the environment is presented, dealing with the uncertainties and imprecision from the sensory system and taking into account nonholonomic constraints of the robot. Fuzzy perception, fuzzy controller...
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