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Guidance system

About: Guidance system is a research topic. Over the lifetime, 4282 publications have been published within this topic receiving 45964 citations.


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Journal ArticleDOI
TL;DR: The results show that the modular structure of the support and guidance system which uses the "magnetic wheel" as a self-contained functional unit is economically feasible within the constraints of existing technology and provides a very promising approach for future tracked high-speed ground transportation systems.
Abstract: The electromagnetic support and guidance system for magnetic levitation railways consists of electromagnets on the vehicle and an armature rail on the track. The experience gained in the operation of the experimental vehicles built so far have lead to the development of a modular structure of the support and guidance system which uses the "magnetic wheel" as a self-contained functional unit. This concept, which is characterized by modular mechanical and electrical structures in connection with decentralized control systems, has made possible a higher reliability by functional redundancy and an improvement of the dynamic characteristics of the vehicle track systems. The results show that such a system is economically feasible within the constraints of existing technology and that it provides a very promising approach for future tracked high-speed ground transportation systems.

42 citations

Patent
19 Dec 2016
TL;DR: In this article, a self-contained, low-cost and low-weight guidance system for vehicles is presented. The guidance system can include an optical camera, a case, a processor, a connection between the processor and an onboard control system, and computer algorithms running on the processor.
Abstract: A self-contained, low-cost, low-weight guidance system for vehicles is provided. The guidance system can include an optical camera, a case, a processor, a connection between the processor and an on-board control system, and computer algorithms running on the processor. The guidance system can be integrated with a vehicle control system through “plug and play” functionality or a more open Software Development Kit. The computer algorithms re-create 3D structures as the vehicle travels and continuously updates a 3D model of the environment. The guidance system continuously identifies and tracks terrain, static objects, and dynamic objects through real-time camera images. The guidance system can receive inputs from the camera and the onboard control system. The guidance system can be used to assist vehicle navigation and to avoid possible collisions. The guidance system can communicate with the control system and provide navigational direction to the control system.

41 citations

Journal ArticleDOI
TL;DR: The proposed output feedback CTSMGL not only guarantees the rates of the line-of-sight angles converge to zero in finite time but also ensures the continuity of control action.

41 citations

Journal ArticleDOI
TL;DR: In this article, the suitability of modified proportional navigation, or an equivalent zero effort miss formulation, for strategic intercepts during midcourse guidance, followed by a ballistic coast to the endgame, is addressed.
Abstract: The suitability of modified proportional navigation, or an equivalent zero effort miss formulation, for strategic intercepts during midcourse guidance, followed by a ballistic coast to the endgame, is addressed. The problem is formulated in terms of relative motion in a general, three-dimensional framework. The proposed guidance law commands thrust 1) along the line of sight unit direction and 2) along the zero effort miss component that is perpendicular to the line of sight. The latter term is scaled with a guidance gain. If the guidance law is to be suitable for longer range targeting applications with significant ballistic coasting after burnout, zero effort miss computations must account for the different gravitational accelerations experienced by each vehicle. Approximations for the true differential gravity effect, which relieve the burden for direct numerical propagation of the governing equations, are considered. Approximations considered are constant, linear, quadratic, and linearized inverse square models. Theoretical results are applied to a numerical engagement scenario, and the resulting performance is evaluated in terms of the miss distances determined from nonlinear simulation.

41 citations

01 Jan 2004
TL;DR: In this article, a line-of-sight motivated control law that globally stabilizes an underactuated ship is derived using output redefinition and cascaded systems theory, based on a general nonlinear ship model with surge propeller force and rudder moment as control inputs.
Abstract: This paper considers way-point manoeuvering in three degrees of freedom (surge, sway and yaw). A line-of-sight motivated control law that globally� -exponentially stabilizes an underactuated ship is derived using output redefinition and cascaded systems theory. The control law development is based on a general nonlinear ship model with surge propeller force and rudder moment as control inputs. Simulation results on a full scale model of a supply vessel are presented. I. INTRODUCTION The route of a ship is usually specified in terms of way- points (1). The way-points are selected taking into account a number of features like weather conditions, obstacle avoid- ance and mission planning. Each way-point is defined in Cartesian coordinates+{l>|l, forl@4===s . The reference trajectory is then made up by straight lines connecting the s way-points. When the ship reaches a prescribed circle, the circle of acceptance, about way-point l, the reference trajectory is switched to the straight line connecting way- points l and l.4. Alternatively, circle arcs connecting the straight lines can be used to define the desired turn at each way-point. In this paper we consider the problem of designing a controller that makes the ship follow the straight lines between way-points, and at the same time controls the forward speed to a constant desired speed xg , i.e. we consider a way-point manoeuvering control problem. Conventional ships are usually equipped with one or two main propellers for forward speed control, and rudders for course control. Even if equipped with side thrusters, these will not give a significant force at transit speeds. This means that we only have independent controls in two degrees of freedom (DOF), surge and yaw, while we seek to control all three degrees of freedom (surge, sway and yaw) of the ship. The path following, tracking and manoeuvering problems are hence underactuated control problems. In conventional way-point guidance systems the output space is reduced such that the number of outputs equals the number of control inputs, and in this way a fully actuated control problem is obtained. It is most often the yaw angle and surge velocity that are controlled. The desired yaw angle#g is then usually chosen using a line- of-sight (LOS) algorithm, while the desired forward speed is constant. Recent research, however, aims at controlling all 3DOF of the ship using only the two available control inputs. Furthermore, while conventional way-point guidance

41 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202319
202252
202197
2020141
2019194
2018206