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This paper studies an optimal autonomous underwater vehicule (AUV) path planning method for both reducing average delay before pollutants detection in underwater mining, oil or gas fields and reducing AUV occupancy time. The proposed technique, based on the bayesian search theory framework and multi-objective optimization, extracts optimal boustrophedon paths for leak detection in complex environment...
This paper focuses on the inspection for sloping dam wall by a remotely operated vehicle (ROV). First, a dedicated ROV for dam inspection is described. Second, a fixed-distance tracking control strategy is proposed to guarantee the fixed camera-to-subject distance in sloping dam inspection, which is instrumental in sonar image fusion for the large-scale dam wall with a certain inclination. In addition,...
With the growth of crowd phenomena in the real world, crowd scene understanding is becoming an important task in anomaly detection and public security. Visual ambiguities and occlusions, high density, low mobility and scene semantics, however, make this problem a great challenge. In this paper, we propose an end-to-end deep architecture, Convolutional DLSTM (ConvDLSTM), for crowd scene understanding...
A complex activity is a temporal composition of sub-events, and a sub-event typically consists of several low level micro-actions, such as body movement of different actors. Extracting these micro actions explicitly is beneficial for complex activity recognition due to actor selectivity, higher discriminative power, and motion clutter suppression. Moreover, considering both static and motion features...
This paper deals with automatic estimation of the horizon in videos from fixed surveillance cameras. The proposed algorithm is fully automatic in the sense that no user input is needed per-camera and it works with various scenes (indoor, outdoor, traffic, pedestrian, livestock, etc.). The algorithm detects moving objects, tracks them in time, assesses some of their geometric properties related to...
Obstacle detection and tracking is a fundamental task for several Advanced Driver Assistance Systems (ADAS) and self-driving cars. Several approaches have been presented in the literature in the last years and many of them are based on visual sensors. In this paper we propose an approach that uses only stereo cameras to detect and track obstacles and compute visual odometry to get the vehicle's ego-velocity...
This paper proposes a new approach for analysing crowded video scenes. The proposed approach decomposes the scene motion dynamics into a graph of interconnected atomic elements of coherent motions named Motion Units (MUs). Different MUs cover scene's local regions with different size and shape, which can even overlap. MUs relationships are analysed to discover the scene entrances and exits. Dominant...
We introduce a novel semi-supervised video segmentation approach based on an efficient video representation, called as “super-trajectory”. Each super-trajectory corresponds to a group of compact trajectories that exhibit consistent motion patterns, similar appearance and close spatiotemporal relationships. We generate trajectories using a probabilistic model, which handles occlusions and drifts in...
This work presents a mixed reality environment for orthopaedic interventions that provides a 3D overlay of Cone-beam CT images, surgical site, and real-time tool tracking. The system uses an RGBD camera attached to the detector plane of a mobile C-arm, which is a typical device to acquire X-Ray images during surgery. Calibration of the two devices is done by acquiring simultaneous CBCT and RGBD scans...
Autonomous electric vehicle path following area has known wide improvement during the last previous years especially with the appearance of new sophisticated control algorithms. The main focus of these control algorithms is to guarantee high performance in term of stability and path tracking with small distance error. In this research, an overview about the most common technics used in autonomous...
Currently deployed wireless and cellular positioning techniques are optimized for outdoor operation and cannot provide highly accurate location information in indoor environments. Meanwhile, new applications and services for mobile devices, including the recent Enhanced 911 (E911), require accurate indoor location information up to the room/suite level. In this work, a new system for improving indoor...
Fully automated vehicles and mobile robots operate in a shared environment with pedestrians. To minimize the risk for pedestrians, it is very important to track them in a precise way. As cameras are often installed in surveillance situations, they are used for tracking pedestrians in a shared environment. To improve the accuracy of the tracking, it is necessary to include all available context information...
Formation-containment tracking problems for high-order linear multi-agent system on directed graphs are studied, where the multi-agent system is composed of a virtual leader, several real leaders and followers. The real leaders need to not only accomplish a predefined time-varying formation but also track the expected trajectory generated by the virtual leader, while the followers are required to...
Anti-torpedo torpedoes (ATT), as a kind of new defense underwater weapon, are widely applied on the active defense systems. In order to effectively combat the target, ATT needs better manipulation and faster navigation strategy. In the present paper, the guided trajectory of ATT is studied in detail by motion simulation. In order to study the guided trajectory characteristics of ATT, the kinematics...
This paper studies the velocity decision making problem for nonholonomic wheeled mobile agents under acceleration constrains. Given the attitudes and velocities information of nonholonomic wheeled mobile agent at start point (SP) and end point (EP), the date of motion trajectory is generated based on the cubic Bezier curve. Then, the decision of time optimal maximum allowable velocity trajectory is...
Traffic behavioral monitoring within urban intersections is an essential issue in the Intelligent Transportation Systems (ITS) for a smart city. This paper investigates on gathering traffic information within an urban intersection where accidents frequently occur. In this paper, traffic pattern modeling, trajectory classification and a real-time vehicle tracker within the urban intersection are proposed...
Permanent magnet linear motors (PMLM) are widely used in high precision machineries. With the removal of the transmission elements, the positioning performances of PMLM are easily affected by parameter variations and external disturbances. Various control approaches were proposed, yet it was noticed that majority of these controllers have complex design procedures, and require accurate model parameters...
This paper presents an implementation and an experimental validation of a virtual structure and a leader-follower flexible formation tracking controllers for car-like non-holonomic mobile robots with velocity and steering controllers in the loops. The formations are flexible in the sense that their formation configurations are defined based on curvilinear longitudinal and lateral relative separations...
This paper introduces the planning algorithm Sa-feRRT, which extends the rapidly-exploring random tree (RRT) algorithm by using feedback control and positively invariant sets to guarantee collision-free closed-loop path tracking. The SafeRRT algorithm steers the output of a system from a feasible initial value to a desired goal, while satisfying input constraints and non-convex output constraints...
For the understanding of the dynamics inside crowds reliable empirical data are needed. On that basis the safety and comfort for pedestrians can be increased and models reflecting the real dynamics can be designed. For that purpose we are developing the free framework PeTrack collecting data from laboratory experiments. With the new integration of the detection of individual codes the presented framework...
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