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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: In this paper, a carrier-phase differential GPS (CPDGPS) based sensor system for automatic tractor control has been developed and demonstrated using a medium-sized Deere 7800 tractor.

146 citations

Journal ArticleDOI
TL;DR: This paper investigates the possibility of achieving precision agriculture control along recorded paths with a CP-DGPS as the unique sensor, and a nonlinear velocity independent control law is designed, relying on chained systems properties.
Abstract: Precision agriculture involves very accurate farm vehicle control along recorded paths, which are not necessarily straight lines. In this paper, we investigate the possibility of achieving this task with a CP-DGPS as the unique sensor. The vehicle heading is derived according to a Kalman state reconstructor, and a nonlinear velocity independent control law is designed, relying on chained systems properties. Field experiments, demonstrating the capabilities of our guidance system, are reported and discussed.

145 citations

Journal ArticleDOI
TL;DR: In this paper, a nonlinear suboptimal guidance law is presented for successful interception of ground targets by air-launched missiles and guided munitions, which accurately satisfies terminal impact angle constraints in both azimuth as well as elevation simultaneously.
Abstract: A nonlinear suboptimal guidance law is presented in this paper for successful interception of ground targets by air-launched missiles and guided munitions. The main feature of this guidance law is that it accurately satisfies terminal impact angle constraints in both azimuth as well as elevation simultaneously. In addition, it is capable of hitting the target with high accuracy as well as minimizing the lateral acceleration demand. The guidance law is synthesized using recently developed model predictive static programming (MPSP). Performance of the proposed MPSP guidance is demonstrated using three-dimensional (3-D) nonlinear engagement dynamics by considering stationary, moving, and maneuvering targets. Effectiveness of the proposed guidance has also been verified by considering first. order autopilot lag as well as assuming inaccurate information about target maneuvers. Multiple munitions engagement results are presented as well. Moreover, comparison studies with respect to an augmented proportional navigation guidance (which does not impose impact angle constraints) as well as an explicit linear optimal guidance (which imposes the same impact angle constraints in 3-D) lead to the conclusion that the proposed MPSP guidance is superior to both. A large number of randomized simulation studies show that it also has a larger capture region.

144 citations

Journal ArticleDOI
TL;DR: In this article, a time-varying linear pursuit game model with bounded controls is presented that can be used to analyze future end-game interception scenarios of autonomous uncrewed e ying vehicles.
Abstract: Future end game interception scenarios of autonomous uncrewed e ying vehicles are expected to be characterized by variable velocities and lateral acceleration limits. A time-varying linear pursuit ‐evasion game model with bounded controls is presented that can be used to analyze such scenarios. The usefulness of this model is demonstrated by simulations of a realistic ballistic missile defense scenario, as an example. It is shown that a differential game guidance law derived using this time-varying model provides a signie cant improvement in the homing accuracy compared to a guidance law based on a model with constant velocities and lateral acceleration limits. Moreover, the time-varying linear model provides a much more accurate prediction of the miss distance, cone rming its validity. Also a general review of possible structures of the game space decomposition is presented. Oneofthese structuresimpliesthateven ifthepursuerdoesnot havea maneuverability advantage overtheevader, but has an agility advantage, a zero miss distance can still be achieved for some initial conditions.

141 citations

Book ChapterDOI
01 Jan 2009
TL;DR: In this paper, the authors consider the concept of guided motion control for marine vehicles, in particular focusing on underactuated marine surface vehicles, and define the control objectives associated with each scenario as work-space tasks instead of configurationspace tasks.
Abstract: A mix between a monograph and an article collection, this PhD thesis considers the concept of guided motion control for marine vehicles, in particular focusing on underactuated marine surface vehicles. The motion control scheme is defined to involve the combination of a guidance system which issues meaningful velocity commands with a velocity control system which has been specifically designed to take vehicle maneuverability and agility constraints into account when fulfilling these commands such that a given motion control objective can be achieved in a controlled and feasible manner without driving the vehicle actuators to saturation. Furthermore, motion control scenarios are classified in a novel way according to whether they involve desired motion which has been defined a priori or not. Consequently, in addition to the classical scenarios of point stabilization, trajectory tracking, path following and maneuvering, the so-called target tracking scenario is considered. The resulting scenarios then involve target tracking, path following, path tracking and path maneuvering. In addition, it is proposed to define the control objectives associated with each scenario as work-space tasks instead of configurationspace tasks. Such a choice seems better suited for practical applications, since most vehicles operate in an underactuated configuration exposed to some kind of environmental disturbances. The thesis also proposes a novel mechanization of constant bearing guidance, which is a classical guidance principle well-known in the guided missile literature. This suggestion is motivated by a need to solve the target tracking motion control objective for marine vehicles. The proposed implementation enables explicit specification of the transient rendezvous behavior toward the target by selection of two intuitive tuning parameters. In addition, a singularity-free guidance law applicable to path following scenarios involving regularly parameterized paths which do not need to be arc-length parameterized is proposed. An extension to this guidance law is also suggested in order to enable off-path traversing of regularly parameterized paths for formation control purposes. A novel velocity control system which inherently takes maneuverability, agility and actuator constraints into account is developed for the purpose of controlling underactuated marine vehicles moving at high speed. The system is derived through a design method which involves a control-oriented modeling approach and requires a minimum of system identification tests to be carried out. The thesis also gives a novel overview of the major developments in marine control systems as seen from a Norwegian perspective. The development can be viewed as three waves of control, where the first wave concerned development of novel ship automation technology in the 1960s and 1970s, the second wave involved development of unique dynamic positioning systems in the 1970s and 1980s, while the third wave is expected to encompass the development of unmanned vehicle technology for a large number of maritime applications. A summary of the historical development, present status and future possibilities associated with unmanned surface vehicles (USVs) is also given. Current Norwegian activities are particularly emphasized. Furthermore, an overview of the main formation control concepts applicable to marine surface vehicles is given. A novel formation control functionality named coordinated target tracking is subsequently suggested within a leader-follower framework. Employing a guided motion control system using the suggested mechanization of constant bearing guidance, this functionality is then implemented for two different types of underactuated USVs such that they are able to move in formation with a leader vessel which can maneuver freely without being constrained to any predefined motion pattern. In particular, excerpts from successful full-scale formation control experiments involving a manned leader vessel and the two USVs executing coordinated target tracking at high speed are presented. This functionality currently seems to be unique on a worldwide basis, providing a convenient plug-and-play formation control capability for manned leader vessels involved in maritime survey operations.

136 citations


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