The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
This paper addresses the heterogeneous data registration problem, which is one of the key features for any scene reconstruction and representation, especially for the underwater environment. In this study, we propose a registration method built around a 2D-to-3D feature-based approach that registers high-resolution side-scan sonar images with bathymetric data (topographic 3D point cloud) obtained...
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 presents the development and control of a novel active needle for percutaneous intervention. Using vision feedback of the actual tip of the needle, inverse kinematics based closed loop control in tracking a 3D curved path is performed. Shape Memory Alloy (SMA) wires are deployed as actuators for the developed active needle system. In-air experiments are performed to evaluate and validate...
The paper presents a software system created to allow to use a user-friendly interface in order to describe complex surfaces which a robot system will follow, with applications in robot milling or engraving. The experimental system used for testing is composed by a 6 degree of freedom IRB 140 ABB robot with tools for engraving of milling, having the PC Interface option for communication and a PC which...
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...
Rotor eccentricity in permanent magnet synchronous motors (PMSMs) increases unbalanced magnetic pull and motor vibration resulting in accelerated aging of motor components. If eccentricity remains undetected, it can increase in severity, and increase the risk of stator-rotor contact, which causes forced outage of the motor and driven process. Detection of eccentricity currently relies on off-line...
This paper presents a self-memory prediction model to mitigate the effects of image based visual servoing (IBVS) system under uncertainty. The performance of IBVS system is easily influenced by different tasks, diverse environments and uncertain disturbances. Through building a self-memory prediction model to keep previous movement tendency in the every current movement, the framework of a self-memory...
Drones equipped with cameras are emerging as a powerful tool for large-scale aerial 3D scanning, but existing automatic flight planners do not exploit all available information about the scene, and can therefore produce inaccurate and incomplete 3D models. We present an automatic method to generate drone trajectories, such that the imagery acquired during the flight will later produce a high-fidelity...
We introduce SceneNet RGB-D, a dataset providing pixel-perfect ground truth for scene understanding problems such as semantic segmentation, instance segmentation, and object detection. It also provides perfect camera poses and depth data, allowing investigation into geometric computer vision problems such as optical flow, camera pose estimation, and 3D scene labelling tasks. Random sampling permits...
In this paper we propose a new protocol based on Virtual Reality and a low-cost haptic device for evaluating motion performance during perturbed 3D reaching tasks. The protocol presented herein was designed to assess how different force amplitudes and different reaching directions influence motor performance of healthy subjects. We developed a novel gaming scenario using Unity 3D and the Novint Falcon,...
Visualization combining space and time in a single display called “space time cube (STC)” is used for visualizing spatio-temporal movement data. An STC enables us to explore not only shapes and positions of vehicle trajectories but also their temporal distributions. However, it is difficult for users to manually find optimal viewpoints for understanding such characteristics of trajectories. In this...
Modelling and digitizing performing arts through motion capturing interfaces is an important aspect for the analysis, processing and documentation of intangible cultural heritage assets. However, existing modelling approaches may involve huge amounts of information which are difficult to process, store and analyze. To address these limitations, usually a skeleton describing the dancer motion is extracted...
In this paper a proof-of-concept of three-dimensional inverse synthetic aperture radar (ISAR) imaging of a rotating airborne target is presented. The authors describe an attempt to obtain 3D imaging of a moving airplane in a bistatic situation. The simulation scenario is presented and the imaging results are depicted. The results are commented on and conclusions drawn.
This paper proposes a distributed 3D pose synchronization law to achieve a common pose with a desired trajectory for a group of quadrotors. The dynamics of networked quadrotors is first derived, and a pose synchronization scheme is proposed. In the present controller design, linear approximation and passivation techniques are employed, which respectively enable to independently handle the yaw angle,...
In this paper, we address the data collection planning problem for fixed-wing unmanned aircraft vehicle (UAV) with a limited travel budget. We formulate the problem as a variant of the Orienteering Problem (OP) in which the Dubins airplane model is utilized to extend the problem into the three-dimensional space and curvature-constrained vehicles. The proposed Dubins Airplane Orienteering Problem (DA-OP)...
The ability to identify, follow, approach, and intercept a non-stationary target is a desirable capability of autonomous micro aerial vehicles (MAV) and puts high demands on reliable target perception, fast trajectory planning, and stable control. We present a fully autonomous MAV that lands on a planar platform mounted on a ground vehicle, relying only on onboard sensing and computing. We evaluate...
Cardiovascular diseases are the leading cause of death globally. Such diseases may affect the left ventricular function, which in turn is closely related to the left ventricular stiffness. Estimation of cardiac deformation can give information on the myocardial stiffness, and may therefore be important in assessment of cardiovascular diseases. A 3D motion estimation scheme is necessary to measure...
In this paper we propose an effective vision-based navigation method that allows a multirotor vehicle to simultaneously reach a desired goal pose in the environment while constantly facing a target object or landmark. Standard techniques such as Position-Based Visual Servoing (PBVS) and Image-Based Visual Servoing (IBVS) in some cases (e.g., while the multirotor is performing fast maneuvers) do not...
Brain tumors therapy is limited by the Blood-Tumor Barrier (BTB) and Blood-Brain Barrier (BBB), still intact in the infiltrative areas. Low intensity Focused Ultrasound (FUS) in conjunction with microbubbles is the only method allowing the local disruption of the BTB/BBB [Hynynen et al. 2001, Zhao et al. 2015]. Proper study of the influence of acoustic scanning parameters (duty cycle, number of focal...
Several challenges limit the use of Pulsed Wave (PW) Doppler to assess coronary blood flow: 1) Transit time effect causes spectral broadening in regions with high blood flow such as stenoses, leading to overestimation of maximum velocities. 2) High beam to flow angles (>60°) and out of plane components often occur, making manual positioning of the sample volume and angle correction difficult. 2D...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.