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 stability and tracking control problem of quadrotor unmanned flying vehicle (UAV) in the presence of uncertainty. Adaptive autonomous sliding mode tracking system is designed by combining robust and adaptive control theory. Lyapunov analysis shows that the proposed algorithms can guarantee asymptotic convergence of the tracking error of the linear and angular motion dynamics...
A robust control is developed for the system of aerospace vehicle via variable robustness control (VRC) algorithm. Aerospace vehicle dynamics contain uncertainties due to cross coupling between longitudinal and lateral dynamics. The proposed scheme makes the system of aerospace vehicle impervious of uncertainties ensuring high performance. The variable robustness control technique is based upon scenario...
In this paper, we deal with the stability and tracking control problem of quadrotor unmanned aerial vehicle (UAV) in the presence of the modeling error and disturbance uncertainty. The flight tracking control system combines classical proportional-derivative (PD) like term with robust and adaptive control term. Lyapunov method is used to design and show the asymptotic behavior of the linear and angular...
This paper presents an intention-aware online planning approach for autonomous driving amid many pedestrians. To drive near pedestrians safely, efficiently, and smoothly, autonomous vehicles must estimate unknown pedestrian intentions and hedge against the uncertainty in intention estimates in order to choose actions that are effective and robust. A key feature of our approach is to use the partially...
Recent successful approaches to autonomous vehicle localisation and navigation typically involve 3D LIDAR scanners and a static, curated 3D map, both of which are expensive to acquire and maintain. In this paper we propose an experience-based approach to matching a local 3D swathe built using a push-broom 2D LIDAR to a number of prior 3D maps, each of which has been collected during normal driving...
Metamodeling techniques using computational intelligence have been used in Uncertainty-based Design Optimization (UDO) to reduce the high computational cost of the uncertainty analysis and improve the performance of stochastic optimization problems with computationally expensive simulation models. Optimal trajectory generation is a major part of Space Launch Vehicle (SLV) design and if it is robust...
Automatic guided vehicles (AGVs), an industrial form of a mobile robot, typically navigate using a central computer commanding AGV movement on predefined paths. How well they follow these paths is not well-defined in research articles and their performance is reported in non-standard manufacturer specifications. Furthermore, AGV technology is advancing towards vision guidance to map and localize their...
In this paper, we present a hardware in the loop simulation of our proposed multi-surface sliding control (MSSC) for trajectory tracking of 6 degrees of freedom (6-DOF) inertia coupled aerial vehicles with multiple inputs and multiple outputs (MIMO). Using MSSC on MIMO autonomous flight systems creates confluent control that can account for both matched and mismatched uncertainties, system disturbances...
This paper studies the application of sliding mode control (SMC) using the nonlinear sliding surface for yaw rate tracking of active front steering (AFS) control. The nonlinear vehicle model is described to simulate the vehicle plant while the linear uncertain vehicle model with uncertainty of cornering stiffness is established for controller design and analysis. The design of nonlinear sliding surface,...
This paper presents a novel way to approach the problem of how to adaptively sample the ocean using fleets of underwater gliders. The technique is particularly suited for those situations where the covariance of the field to sample is unknown or unreliable but some information on the variance is known. The proposed algorithm, which is a variant of the well-known fuzzy C-means clustering algorithm,...
A mathematical model of agent-based decision-making of Autonomous Surface Vehicles (ASVs) is presented with extensive path planning and abstraction capabilities of the environment. The aim is to enable the ASV to pass through heavy harbour traffic to an intended destination safely and efficiently. While predicting the future path of other vehicles and path planning can be carried out by known methods,...
This paper addresses the challenge of dynamically adapting the location of the nodes in an acoustic network to optimise the localisation performance of Autonomous Underwater Vehicles (AUVs) operating in the area. A dynamic placement algorithm is presented to minimise the Cramer-Rao Lower Bound associated to the connected subset of network nodes. Algorithm performance is shown in simulation and as...
An adaptive dynamic surface control algorithm is proposed for longitudinal attitude of the hypersonic vehicle in the presence of angle of attack constraints. The angle of attack constraints are firstly converted into the tracking error constraints, and then a weighted performance function and an error transformation technique are introduced, which guarantee a prescribed performance of tracking error...
Real-world autonomous driving in city traffic must cope with dynamic environments including other agents with uncertain intentions. This poses a challenging decision-making problem, e.g., deciding when to perform a passing maneuver or how to safely merge into traffic. Previous work in the literature has typically approached the problem using ad-hoc solutions that do not consider the possible future...
This paper presents a novel path planning method for minimizing the energy consumption of an autonomous underwater vehicle subjected to time varying ocean disturbances and forecast model uncertainty. The algorithm determines 4-Dimensional path candidates using Nonlinear Robust Model Predictive Control (NRMPC) and solutions optimised using A*-like algorithms. Vehicle performance limits are incorporated...
Any signal processing methodology when blindly applied to realistic data sets generates a significant number of false targets along with estimates for the true moving targets. In an effort to isolate the true movers from the false targets, a new approach exploiting spatio-temporal connectivity in addition to signal processing algorithms involving imaging and interferometry is proposed here to geolocate...
This paper deals with the identification of the physical parameters of a passenger car. After studying the local structural identifiability of two models of different complexity, the identifiable parameters which are unknown or difficult to measure are identified by minimising a multivariable, cost criterion in terms of maximum likelihood. The choice of the optimisation algorithm is considered, before...
This work presents new results for state estimation based on noisy observations suffering from two different types of uncertainties. The first uncertainty is a stochastic process with given statistics. The second uncertainty is only known to be bounded, the exact underlying statistics are unknown. State estimation tasks of this kind typically arise in target localization, navigation, and sensor data...
In this paper the problem of vehicle lateral control in highway experimental conditions is addressed. The vehicle under consideration is equipped with an electric motor acting on the steering angle (the command input) and a vision system providing two measurements (the two outputs): the lateral displacement and the angular orientation of the vehicle with respect to the lane centerline. We show how,...
This paper presents an active steering strategies for a railway vehicle to improve performances on curves. By feeding forward a desired angle of attach and the radius of curves, a feedforward control law is proposed and verified. In order to assess its performance issue, parameter variations such as creep coefficients and nonlinearities of the wheel conicity are considered. The simulation results...
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.