Showing papers on "Guidance system published in 2010"

A Vision-Based Guidance System for UAV Navigation and Safe Landing using Natural Landmarks

Abstract: In this paper a vision-based approach for guidance and safe landing of an Unmanned Aerial Vehicle (UAV) is proposed. The UAV is required to navigate from an initial to a final position in a partially known environment. The guidance system allows a remote user to define target areas from a high resolution aerial or satellite image to determine either the waypoints of the navigation trajectory or the landing area. A feature-based image-matching algorithm finds the natural landmarks and gives feedbacks to an onboard, hierarchical, behaviour-based control system for autonomous navigation and landing. Two algorithms for safe landing area detection are also proposed, based on a feature optical flow analysis. The main novelty is in the vision-based architecture, extensively tested on a helicopter, which, in particular, does not require any artificial landmark (e.g., helipad). Results show the appropriateness of the vision-based approach, which is robust to occlusions and light variations.

Adaptive surveillance and guidance system for vehicle collision avoidance and interception

Abstract: A surveillance and guidance method and system for use with autonomously guided, man-on-the-loop or man-in-the-loop guided vehicles where the presence of obstacles must be considered in guiding the vehicle towards a target includes a navigation system configured to determine the position of the vehicle on which it is equipped. A communication system is configured for data exchange between the vehicle, neighboring vehicles and ground stations. A surveillance system is configured to detect and locate fixed or moving targets and obstacles. A computer is configured to track the position of targets and obstacles and to provide guidance commands or 4D flight paths to perform collision avoidance with respect to traffic regulations and procedures, and operational airspace restrictions. Additional computer tasks include station keeping or interception of targets. A command and control system is configured to interact with a user interface and control the vehicle's actuators.

Ground Vehicle Dynamics

Abstract: System Definition and Modeling.- Vehicle Models.- Models for Support and Guidance Systems.- Guideway Models.- Models for Vehicle-Guideway-Systems.- Assessment Criteria.- Computational Methods.- Longitudinal Motions.- Lateral Motions.- Vertical Motions.

Gnss integrated multi-sensor control system and method

Abstract: A GNSS integrated multi-sensor guidance system for a vehicle assembly includes a suite of sensor units, including a global navigation satellite system (GNSS) sensor unit comprising a receiver and an antenna. An inertial measurement unit (IMU) outputs vehicle dynamic information for combining with the output of the GNSS unit. A controller with a processor receives the outputs of the sensor suite and computes steering solutions, which are utilized by vehicle actuators, including an automatic steering control unit connected to the vehicle steering for guiding the vehicle. The processor is programmed to define multiple behavior-based automatons comprising self-operating entities in the guidance system, which perform respective behaviors using data output from one or more sensor units for achieving the behaviors. A GNSS integrated multi-sensor vehicle guidance method is also disclosed.

Synthetic-Waypoint Guidance Algorithm for Following a Desired Flight Trajectory

Abstract: T HE development of aircraft guidance, navigation, and control systems has been a long-standing research area. Numerous methods relating to the enhancement of aircraft performance under various mission parameters have been developed in response to a need for more reliable and robust guidance systems. Current guidance systems applied to commercial, civilian, and unmanned aircraft rely on the knowledge of a flight path, specified bywaypoints located in inertial space. Most missions are considered successful when the vehicle reaches the designatedwaypoint at which new commands are issued to the vehicle to proceed to the next waypoint. Two common types of conventional aircraft guidance are the direct-to-waypoint (DTW) and track-to-waypoint (TTW) methods in relation to pathfollowing between designated waypoints. The DTWmethod simply issues heading commands to the vehicle based on the angular difference between thewaypoint and vehicle.When thevehicle reaches the waypoint, the control system issues a new command to guide the aircraft to the next waypoint. The TTW method aims to follow the track betweenwaypoints. In this guidancemethod the control system aims to minimize the lateral offset between the prescribed flight path and the aircraft’s position, issuing heading commands that return the vehicle to the nominal flight path. The track method therefore places the additional constraint on a flight path that the vehicle must follow in order to reach the waypoint, rather than simply reaching the waypoint. However, both methods are far from optimal. This is evident in how the aircraft transitions between flight paths after reaching awaypoint. During theseflight-path transitions, the aircraft will often overshoot the desiredflight path to correct its track, particularlywhen the flight-path transition angle is acute. Various control strategies have been investigated to alleviate or minimize flight-path deviations. Such strategies include applyingmodern control methods such as receding-horizon control [1,2] and model predictive control [3] to anticipate flight-path changes and take control action before reaching a goal while maintaining adequate vehicle flight performance. Missile guidance and control systems operate on similar principles to commercial, civilian, and unmanned aircraft guidance and control algorithms. The primary mission for missile systems is to intercept a moving target using information about the relative position and velocity between the pursuer and target. One of thefirstmethods used in missile guidance was pursuit guidance (PG) [4–7]. The method operates by forcing the angular displacement error between a pursuer and its target to zero. Control commands scaled by a proportional factor of the current error are then issued to direct the pursuer along the line of sight (LOS) between the pursuer and target. PG solutions, however, do not consider the path taken or the levels of system performance required by the pursuer in reaching the target, resulting in a far-from-optimal solution. To address this problem of suboptimality, additional parameters have been introduced to enhance missile performance. One method includes taking into account the motion of the commanded line of sight between the pursuer and target [4,7–10], issuing lateral acceleration commands based on tracking error and tracking error rate to the target. This approach has been shown to improve overall interceptor performance compared with conventional PG [4,7]. Another suchmethod aims tomodify the level of control the guidance algorithm possesses over the vehicle by adjusting the level of proportional gain. This is achieved by gain scheduling [11] to select gain values based on current interceptor states. In addition to modifying internal missile guidance and control parameters such as variable gains and LOS rate estimation, mission performance can be enhanced by manipulating the trajectory taken by the pursuer to the targets. A good example of such a method is discussed in [12], in which a missile aims to exploit the aerodynamic benefits of high-altitude flight by tracking a virtual target at some initially high altitude that is not necessarily along the trajectory to the true target. This Note discusses the development of a guidance law fusing the virtual-target concepts with those of pursuit guidance for implementation into an aircraft guidance system. This Note develops a path-following aircraft guidance algorithm that pursues synthetic waypoints using only a small set of guidance parameters, extending the virtual-target concept to complete aircraft guidance. The path is defined by the track between a minimal set of waypoints at specified locations, removing the need for a smooth path to be defined or the need for complicated path-switching logic or trajectory planning when awaypoint is reached. The synthetic waypoint travels along the path between waypoints, with the trailing aircraft traveling a smooth path generated through its own dynamics in following the synthetic waypoint. The guidance law is tested by varying guidance parameters, thus assessing vehicle sensitivity to and overall system performance of parameter variations. The following sections discuss the basic concepts of missile and aircraft guidance and provide a detailed description of the structure of the synthetic-waypoint guidance algorithm. A discussion on the implementation of the algorithm into the underlying aircraft control system will also be presented, followed by an analysis of the performance of the guidance algorithm in nonlinear simulation. Received 30 June 2009; revision received 3 November 2009; accepted for publication 9November 2009.Copyright©2009 by theAmerican Institute of Aeronautics and Astronautics, Inc. All rights reserved. Copies of this paper may be made for personal or internal use, on condition that the copier pay the $10.00 per-copy fee to the Copyright Clearance Center, Inc., 222 Rosewood Drive, Danvers, MA 01923; include the code 0731-5090/10 and $10.00 in correspondence with the CCC. ∗Graduate Research Student, School of Aerospace, Mechanical and Mechatronic Engineering; e.medagoda@aeromech.usyd.edu.au. Senior Lecturer, School of Aerospace, Mechanical and Mechatronic Engineering; pwg@aeromech.usyd.edu.au. JOURNAL OF GUIDANCE, CONTROL, AND DYNAMICS Vol. 33, No. 2, March–April 2010

Haptic negotiation and role exchange for collaboration in virtual environments

Abstract: We investigate how collaborative guidance can be realized in multi-modal virtual environments for dynamic tasks involving motor control. Haptic guidance in our context can be defined as any form of force/tactile feedback that the computer generates to help a user execute a task in a faster, more accurate, and subjectively more pleasing fashion. In particular, we are interested in determining guidance mechanisms that best facilitate task performance and arouse a natural sense of collaboration. We suggest that a haptic guidance system can be further improved if it is supplemented with a role exchange mechanism, which allows the computer to adjust the forces it applies to the user in response to his/her actions. Recent work on collaboration and role exchange presented new perspectives on defining roles and interaction. However existing approaches mainly focus on relatively basic environments where the state of the system can be defined with a few parameters. We designed and implemented a complex and highly dynamic multimodal game for testing our interaction model. Since the state space of our application is complex, role exchange needs to be implemented carefully. We defined a novel negotiation process, which facilitates dynamic communication between the user and the computer, and realizes the exchange of roles using a three-state finite state machine. Our preliminary results indicate that even though the negotiation and role exchange mechanism we adopted does not improve performance in every evaluation criteria, it introduces a more personal and human-like interaction model.

Basic Principles of Homing Guidance

Abstract: This article provides a conceptual foundation with respect to homing guidance upon which the next several articles are anchored. To this end, a basic geometric and notational framework is first established. Then, the well-known and often-used proportional navigation guidance concept is developed. The mechanization of proportional navigation in guided missiles depends on several factors, including the types of inertial and target sensors available on board the missile. Within this context, the line-of-sight reconstruction process (the collection and orchestration of the inertial and target sensor measurements necessary to support homing guidance) is discussed. Also, guided missiles typically have no direct control over longitudinal acceleration, and they maneuver in the direction specified by the guidance law by producing acceleration normal to the missile body. Therefore, we discuss a guidance command preservation technique that addresses this lack of control. The key challenges associated with designing effective homing guidance systems are discussed, followed by a cursory discussion of midcourse guidance for completeness' sake.

Real-time vehicle route guidance using vehicle-to-vehicle communication

Abstract: With advances in wireless communications and global position system-enabled devices (such as cellular phones, PDAs and car PCs), vehicle route guidance systems gradually become indispensable equipments for more and more automobile drivers because of its great convenience. Conventional route guidance systems are designed to direct a vehicle along the shortest path from the origin to the destination. However, usually, the shortest path does not result in the smallest travel time because of the dynamic traffic conditions on roadways. Therefore the state-of-the-art route guidance systems incorporate real-time traffic information to find better paths. There are two types of approaches to collecting real-time traffic information: infrastructure-based approach and infrastructure-free approach. The authors adopt infrastructure-free approach to develop a real-time route guidance algorithm, called V2R2 (Vehicle-to-Vehicle Real-time Routing). Our simulation results showed that V2R2 algorithm can effectively find better paths with less travel time than the shortest path. In addition, it can bypass void areas (i.e. the areas containing empty roads) when collecting real-time traffic information. The simulation results validate the efficiency and robustness of the proposed V2R2 algorithm.

Fault-Tolerant Model Predictive Control with Flight-Test Results

Abstract: This work presents a novel method of fault-tolerant model predictive control where the response of a reference closed-loop model is followed even in the presence of an actuator fault. This architecture is capable of redistributing the control efforts among healthy actuators in a stable manner, respecting their limitations. Also, a constrained guidance system that works in conjunction with the inner-loop fault-tolerant controller is proposed. The guidance law considers the calculated limitations of the inner-loop control system as input constraints in order to smooth the transition between two consecutive navigation legs defined by waypoints. A trajectory-tracking system composed of the constrained guidance and the fault-tolerant model predictive controller is demonstrated through numerical simulations and experimental results on an experimental midsize transport aircraft, showing adequate performance.

Overview of Missile Flight Control Systems

Abstract: The flight control system is a key element that allows the missile to meet its system performance requirements. The objective of the flight control system is to force the missile to achieve the steering commands developed by the guidance system. The types of steering commands vary depending on the phase of flight and the type of interceptor. For example, in the boost phase the flight control system may be designed to force the missile to track a desired flight-path angle or attitude. In the midcourse and terminal phases the system may be designed to track acceleration commands to effect an intercept of the target. This article explores several aspects of the missile flight control system, including its role in the overall missile system, its subsystems, types of flight control systems, design objectives, and design challenges. Also discussed are some of APL's contributions to the field, which have come primarily through our role as Technical Direction Agent on a variety of Navy missile programs.

Benchmarking of obstacle field navigation algorithms for autonomous helicopters

Abstract: This paper describes a framework for performance evaluation of autonomous guidance systems using benchmarks.The benchmarks consist of six simple problems containing two or fewer geometric primitives, a high resolution height map scanned from an urban area, and a simple vehicle model with hard velocity and acceleration constraints. Performance metrics used to compare trajectories are presented. Two trajectory optimization methods are used to generate near-optimal baseline trajectories: numerical optimization using Nonlinear Programming for simple problems, and the Motion Primitive Automaton for problems with complex terrain. As an example, the Obstacle Field Navigation system developed by the Army Aeroflightdynamics Directorate is compared to the baseline

Parking guidance system

Abstract: The present application discloses a parking guidance system. The parking guidance system is mounted on a vehicle and includes a camera, a display device with a display correction system, a parking mode selection apparatus, a parking area selection apparatus, a first turning guidance apparatus, and a second turning guidance apparatus. The camera is mounted at the rear of the vehicle to capture the image showing environment behind the vehicle. The display device with a display correction system is coupled to the camera and is configured to display an image corrected by the display correction system. The parking mode selection apparatus is coupled to the display device. The parking mode selection apparatus displays a predicted parking area on the display device. The parking area selection apparatus is coupled to the display device. The parking area selection apparatus displays a parking guidance area on the display device. The first turning guidance apparatus is coupled to the display device. The first turning guidance apparatus displays an arc on the display device. The second turning guidance apparatus is coupled to the display device. The second turning guidance apparatus displays on the display device a parking track with distance indication.

GNSS contour guidance path selection

Abstract: A GNSS-based contour guidance path selection system for guiding a piece of equipment through an operation, such as navigating a guide path, includes a processor programmed for locking onto a particular aspect of the operation, such as deviating from a pre-planned or original guidance pattern and locking the guidance system onto a new route guide path, while ignoring other guidance paths. The system gives a vehicle operator control over a guidance route without the need to re-plan a pre-planned route. The device corrects conflicting signal issues arising when new swaths result in the guidance system receiving conflicting directions of guidance where the new swaths cross predefined swaths. An operator can either manually, or with an autosteer subsystem automatically, maintain a new contour guidance pattern, even while crossing predefined guidance paths that would otherwise divert the vehicle.

Design and Implementation of a GPS Guidance System for Agricultural Tractors Using Augmented Reality Technology

Abstract: Current commercial tractor guidance systems present to the driver information to perform agricultural tasks in the best way. This information generally includes a treated zones map referenced to the tractor’s position. Unlike actual guidance systems where the tractor driver must mentally associate treated zone maps and the plot layout, this paper presents a guidance system that using Augmented Reality (AR) technology, allows the tractor driver to see the real plot though eye monitor glasses with the treated zones in a different color. The paper includes a description of the system hardware and software, a real test done with image captures seen by the tractor driver, and a discussion predicting that the historical evolution of guidance systems could involve the use of AR technology in the agricultural guidance and monitoring systems.

Attitude Guidance for Spinning Vehicles with Independent Pitch and Yaw Control

Abstract: The design and simulation of an attitude guidance and control scheme for a spinning aerospace vehicle is detailed. The basis for the guidance law is the projection of the angular-velocity vector onto a plane normal to the desired heading. The result of the projection is an attitude error that can be converted to pitch-and yaw-rate commands for an autopilot. Two single-input/single-output controllers are used in this paper, which in turn issue flap defiection commands. An asymmetrical vehicle spinning at 1.5 Hz with independent pitch-and yaw-flap sets is simulated in a six-degree-of-freedom simulation. It is shown to perform successful attitude maneuvers for two different cases. In one case, the basic guidance law is used. This results in a settling time of approximately 1.0 s. The next case performs the maneuver with a modified guidance law that includes decoupling terms. This case results in a settling time of 0.6 s. The guidance law has a number of possible applications. These include stability augmentation and redundancy, alternatives in fin Configurations for vehicles, and reduction in number of necessary control surfaces. Copyright © 2009.

Missile guidance system

Abstract: In a CLOS missile guidance system, target and missile tracking data e.g. video image data are acquired on a UAV and transmitted to the missile where they are processed to provide guidance control data to the missile. Alternatively the video image data may be transmitted to a command station where the guidance control data is generated and transmitted to the missile, preferably via the UAV.

Remote air-to-air missile multi-platform cooperative guidance system and realization method thereof

Abstract: The invention discloses a remote air-to-air missile multi-platform cooperative guidance system and a realization method thereof. The multi-platform cooperative guidance system comprises an early warning plane module, a ground base radar detecting module, an aerial carrier module, a friend plane module, a remote air-to-air missile module, a target information space-time normalizing module and a target information fusion module. The realization method comprises the following steps: 1. an early warning plane, a ground base radar guided aerial carrier and a friend plane fly to a war area; 2. the radar of the friend plane operates to detect a target, and the aerial carrier launches an air-to-air missile; and 3. the targets detected by the radar of the early warning plane, the ground base radar and the radar of the friend plane are fused, and the friend plane carries out midcourse guide on the air-to-air missile. By adopting a multi-platform combat network formed by the early warning plane, the ground base radar, the aerial carrier and the friend plane to provide high-accuracy target information for the remote air-to-air missile, and adopting the friend plane to perform midcourse guide on the remote air-to-air missile, a remote target can be attacked stealthily and accurately.

A blind guidance system for street crossings based on ultrasonic sensors

Abstract: This paper addresses the technical feasibility of a guidance system based on ultrasonic sensors to aid visually impaired people to cross a road easily and safely. A computer processes ultrasonic signals emitted by a transmitter, which is carried by the impaired user, and provides real-time information on the direction and distance to keep user on the correct track. Instead of time of flight, the system estimates user position by the order of received ultrasonic signals at multiple receivers. Radio transmission is then used to provide guidance information to the user by using of two vibrators that act as tactile feedback. Experimental results are presented to discuss feasibility of this method.

Inertial Navigation for Guided Missile Systems

Abstract: An accurate inertial reference based on measurements of missile angular velocity and acceleration is needed for all of the major guidance and control functions of a guided missile. For example, intercept of a target would not be possible without a good inertial reference system to stabilize target line-of-sight measurements for the computation of missile guidance commands. This article provides an overview of inertial navigation for guided missiles. Missile navigation data (position, velocity, and attitude) are needed for missile guidance and control. Furthermore, this article describes in-flight alignment techniques that can be used to increase the accuracy of the missile navigation-system data by incorporating external non-inertial navigation-aiding data using a navigation Kalman filter. For guided missile systems, this aiding often is provided by an external radar track of the missile and/or Global Positioning System (GPS) receiver measurements. This article also discusses more recent advances in navigation for guided missiles. APL has been a major contributor to the development of many of the advanced guided missile navigation systems in use today.

Location-Based Dynamic Route Guidance System of Korea: System Design, Algorithms, and Initial Results

Abstract: Over the last two years, the Korean Expressway Corporation (KEC) has developed a location-based dynamic route guidance system. The targets of the new system are the users of mobile-phones, the internet, and PDAs (Personal Digital Assistant), etc. Spatially the system covers 2,804 km of expressway and 484 km of national highway where the travel time collection systems are installed. The developed routing system is in many aspects different from the existing telematics-related services in Korea. It is based on predicted traffic information rather than real-time traffic information, and provides web and location based in-vehicle route guidance system. It utilizes GML (Geographical Markup Language) and GIS (Geographical Information System) in order to create GML DB (Data Base), and follows the standard format of the ISO (International Standard Organization) for GDF (Geographic Data File). Initial results of the proposed system including the accuracy of route travel time forecasts and the soundness of suggested routes were found to be acceptable. After development, the KEC has successfully tested a pilot service of the new system and is currently preparing for a full-scale implementation.

View navigation guidance system for hand held devices with display

Abstract: System and method for view navigation guidance system for a physical display that is smaller than the virtual display it needs to display. Guidance map placed in a heads-up display layer within a small user defined area of the physical display provides an instantaneous indication of the current position of the screen view with minimal obstruction of the contents information. Color selection for the guidance map is automatically determined based on the background color in the main display layer beneath the map. The guidance map area on a touch screen display may include tapping controls, and the position of the guidance map can be dynamically altered by the user during the view navigation to control the navigation parameters.

Aircraft guidance system for assisting in airport navigation

Abstract: An aircraft guidance system for assisting in airport navigation includes: at least one airport database comprising topology data of an airport, called airport DB; at least one configuration database comprising aircraft configuration data and the position of a guidance point; a positioning system delivering aircraft kinematic and attitude parameters; at least one computer generating a 2D view of the representation of the airport notably comprising navigation indications and a representation of the aircraft; and at least one display for displaying the representation of the airport. In the system, a first symbol is generated on the display indicating the position of an early guidance point, corresponding to the position of the guidance point at a future time.

Target Maneuver Adaptive Guidance Law for a Bounded Acceleration Missile

Abstract: A new estimator-guidance law is presented, for a bounded acceleration interceptor pursuing a target performing a sudden step maneuver. The linearized end-game scenario is investigated. The missile’s acceleration saturation is represented by the equivalent random input describing function. The estimator proposed for this problem features a mechanism constructed to e‐ciently identify a sudden target maneuver. Due to the bound on the missile acceleration, the certainty equivalence property is not valid, and so, the resulting controller (guidance law) depends on the measurement noise level, statistics of the target maneuver, and the saturation limit. The derivation of this guidance law proceeds in two stages. In the flrst simplifled stage, it is assumed that the instance that the target issues a step command in its acceleration is known. However, the size of the target maneuver jump must still be estimated. Simulation results show signiflcant improvement over the deterministic optimal guidance law when the jump times vary from 10 to 3 missile time constants prior to the intercept time. If the jump occurs earlier or later than this duration no improvement is gained. In the second stage, a suboptimal guidance law is derived using the multiple model adaptive control formulation for a target performing a single step maneuver near the intercept time. Note that this sub-optimal guidance law does not require a-priory knowledge of the time of the jump in the target acceleration command. Performance improvement of the same order of magnitude as was observed for the known jump time scheme (that also serves as a performance bound) is achieved, verifying the validity of this approach. Sensitivity analysis to various noise levels and expected target maneuvers was carried out emphasizing the robustness and advantages of this scheme.

Mobile image-aided guidance method and mobile image-aided guidance system for vehicles

Abstract: The invention discloses a mobile image-aided guidance method and a mobile image-aided guidance system for vehicles, which utilize a single image acquisition device to be matched with a control device with image processing, image identification as well as the estimation and calculation of an image space distance to provide intact image-aided information when the vehicles move. The method can produce movement tracks of the vehicles, perform the conversion of survey perspectives, and identify image characteristics in images for distance estimation. The method and the system can be applied to various different vehicle forms, solve the problem of mobile guidance of the vehicles, and can also assist the vehicles with the lane change, parking assistance and blind-spot detection.

Research on virtual experiment intelligent-tutoring system based on multi-agent

Abstract: The application of virtual experiment changes the traditional mode of education, and makes a fundamental change in the teaching and learning methods. Virtual experiments can effectively overcome a lot of difficulties of practical teaching in schools. Interaction and intelligence of virtual experiment environment is essential. This paper discusses a number of issues on intelligent guidance in virtual experiment, and presents a model for virtual experiment Intelligent Guidance System based on Multi-Agent. Finally, a running example is shown.

Automated catheter guidance system

Abstract: A graphical user interface for controlling and configuring a remote catheter guidance system having the graphical user interface is displayed concurrently with the mapping and navigation display of the remote catheter guidance system and the graphical user interface being configured to allows a user full control of all the remote catheter guidance system movement functions without leaving the mapping and navigation display. The graphical user interface further allows the physician to quickly configure and calibrate a remote catheter guidance system prior to or during a procedure.

Sharing Control with Elderly Drivers: Haptic Guidance during Curve Negotiation

Abstract: Elderly drivers suffer from deterioration of sight and hearing. This makes visual and auditory information for driver support during curve negotiation not very suitable. We present the design and experimental evaluation of a haptic guidance system for curve negotiation. Twelve elderly (>50 years) subjects participated in a fixed-base driving experiment. Based on previous experience with haptic guidance systems, we hypothesized that the benefits of the haptic guidance would be a small increase of curve negotiation performance with less control activity. Results of the experiment show that this was indeed achieved. However, the haptic guidance system resulted in a relatively large increase in steering forces, which could also be a disadvantage for elderly drivers. This needs to be investigated in the future.

Line Tracking Method of AGV using Sensor Fusion

Abstract: *** Abstract This paper present to stu dy the guidance system as localizat ion t echnique using sensor fusion and line t racking technique using virtual line for AG V(autonomous gu ided vehicle) An existing AG V could drive on decided line only And representative guidance systems of such guidance system are magnet-gyro guidance and wired guidance However, t hose have had the high cost of inst allation and maintenance, and the difficulty of syst em change according to variation of working environment To solve such problems, we make the localization syst em which is fused with a laser navigat ion and gyro, encoder The system is robust against noise, and flexible according to working environment through sensor fusion For line tracking of laser navigation withou t wire guidance, we set the virt ual line in program, and design t he driving controller based on difference of angle and distance between AG V's position and decided virtual line To experiment, we use the AG V which is made by ourselves, and experiment t he line tracking repeatedly on same experimental environment In result, maximum distance error between decided virtual line and AG V's position was less than 4993mm, and we verified that t he proposed system is effic ient for line tracking of actu al A GV

Design of variable structure guidance law with constraints on impact angle for anti-ship missile

Abstract: In order to achieve the tactical mission of attacking the target on the appointed direction, the characteristics of maneuver target was analyzed, and a variable structure guidance law with constraints on impact angle, based on the 3-D relative motion model of missile and target, was presented in the point of view of engineering application. The guidance law is simple and can be implemented conveniently with little target information. In the guidance law, the distance between missile and target, and their relative velocity, which is difficult to measure, were substituted by estimation values. The estimation errors, the target's velocity, and the target's maneuver acceleration are all treated as bounded disturbance. And all these disturbances can be successfully restrained by choosing the appropriate parameters of guidance law. The performance of the guidance system was analyzed theoretically, and the numerical simulation result shows the validity and effectiveness of the proposed guidance law.