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Performance measures and adaptive control methodologies for traffic signal systems currently require intersections to be instrumented with vehicle detectors and communication equipment, which can require substantial engineering resources to deploy and maintain. Recent studies have explored the use of Connected Vehicle (CV) data for signal performance measures at various levels of market penetration,...
This paper presents an online optimization-based approach to compute trajectories to enable substitution of robots in formation-based deployments with durations that exceed the energy capacity of individual systems. The proposed algorithm computes trajectories in a multi-robot context to ensure a collision-free exchange, even where congestion is a concern. The quality of the resulting trajectories...
In recent years, location-based services and indoor positioning systems gained increasing importance for both, research and industry. Visual localization systems have the advantage of not being dependent on dedicated infrastructure and thus are especially interesting for navigation within buildings. While there are already approaches of using pre-recorded databases of reference images to obtain an...
In the last couple of years a novel visual simultaneous localisation and mapping (SLAM) system, based on visual features, has emerged as one of the best, if not the best, systems for estimating the 6D camera pose whilst building a 3D map of the observed scene. This method is called ORB-SLAM and one of its key ideas is to use the same visual descriptor, a binary descriptor called ORB, for all the visual...
Perceptual mechanisms humans use in motion planning and guidance are responsible for their agile and versatile capabilities. Their understandings would help advance both autonomous control and improve human-machine interfaces. This paper extends prior work by collecting human trajectory and gaze data while performing simulated first-person motion guidance tasks. This data is considered under the hypothesis...
Modelling car-following in an effective and accurate way is of great importance for several areas of application, such as microscopic traffic simulation and ADAS (Advanced Driving Assistance Systems). Heterogeneity can be observed in driving behaviors if car-following data are analyzed. Part of this dispersion depends on the inherent heterogeneity across drivers, that could react in different ways...
The virtual reconstruction of underwater environments in 3 dimensions can be of great utility for scientific or industrials applications, being the use of Autonomous Underwater Vehicles (AUVs) equipped with cameras an invaluable tool with progressive improvements. However, a highly accurate vehicle localization process is fundamental to place every portion of that 3D model in its real position with...
In this paper, we propose a novel visual analysis method TrajRank to study the travel behaviour of vehicles along one route. We focus on the spatial-temporal distribution of travel time, i.e., the time spent on each road segment and the travel time variation in rush/non-rush hours. TrajRank first allows users to interactively select a route, and segment it into several road segments. Then trajectories...
This paper presents a method for detecting city-scale changes of a city from its street images and a 2D map. Using SfM to reconstruct point cloud of the structures of the city, the method estimates the existence of each building by matching the point cloud with the 3D building structures recovered from the map. There are multiple difficulties, such as inaccuracy of the recovered building structures,...
This paper presents a computational system to perform, simultaneously, the control of th 3D position and trajectory of two commercial unmanned aerial vehicles (UAVs), the Parrot AR. Drone quad copter. The developed system runs in a main computer, allowing the automatic control of the vehicles in flight missions. In this work, are presented the experimental platform, the mathematical and the computational...
This paper presents a solution to the 3D Range-Only beacon localization problem using a Sum of Gaussians (SOG) filter together with an Active Localization method, which is based on the minimization of the beacon position uncertainty, in order to ensure the problem observability and a fast convergence. The method is applied to autonomously locate a subsea panel and home to it in order to establish...
Inspection and exploration of complex underwater structures requires the development of agile and easy to program platforms. In this paper, we describe a system that enables the deployment of an autonomous underwater vehicle in 3D environments proximal to the ocean bottom. Unlike many previous approaches, our solution: uses oscillating hydrofoil propulsion; allows for stable control of the robot's...
Modeling and simulating of pedestrians movement have attracted much attention because they provide reproducible results, which are important to evaluate evacuation facilities and risks. It is well accepted the movement of individuals is affected by interactions with others and the environment. However, factors affecting the interactions are not fully studied and experiments are needed. This paper...
This paper provides a preliminary analysis of an autonomous uncooperative collision avoidance strategy for unmanned aircraft using image-based visual control. Assuming target detection, the approach consists of three parts. First, a novel decision strategy is used to determine appropriate reference image features to track for safe avoidance. This is achieved by considering the current rules of the...
This paper presents Sequence Matching Across Route Traversals (SMART); a generally applicable sequence-based place recognition algorithm. SMART provides invariance to changes in illumination and vehicle speed while also providing moderate pose invariance and robustness to environmental aliasing. We evaluate SMART on vehicles travelling at highly variable speeds in two challenging environments; firstly,...
This paper presents an autocalibration method to determine the pose of a stereo vision system based on knowing the geometry of the ground in front of the cameras. This pose changes considerably while the vehicle is driven, therefore it is good to know constantly the pose of the camera for several applications based on computer vision, such as advanced driver assistance systems, autonomous vehicles...
Underwater autonomous robots with 6 degrees of freedom (DOF), equipped with low cost aided inertial navigation systems, usually make use of Kalman Filters (KF) to fuse, in a single vector, the measurements given by multiple sensors. In this context, Multiplicative Error State Kalman Filters (MESKF) are preferable than standard KFs to increase the reliability of the vehicle motion estimates. This particular...
Nowadays, big cities are suffering from severe traffic congestion as a result of the continuing increase in vehicles. Taxis equipped with GPS can be viewed as sensors of the traffic situation in city. However, trajectory data generated by taxi's GPS traces are often high-dimensional and contain large spatial and temporal attributes, which pose challenges for analysts. In this paper, based on taxi...
This paper addresses platooning navigation as part of new transportation services emerging nowadays in urban areas. Platooning formation is ensured using a global decentralized control strategy supported by inter-vehicle communications. A large motion flexibility is achieved according to a manual guidance mode, i.e. the path to follow is inferred online from the motion of the manually driven first...
Haptic shared control is a powerful way of combining the best of humans and intelligent vehicles, keeping humans in the loop while avoiding many automation issues. Literature has shown that haptic shared control can support drivers to increase performance at reduced control effort, but also points out that even then, subtle conflicts occur between driver and shared controller. This paper hypothesizes...
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