Showing papers on "Guidance system published in 2002"

Nonlinear formation control of marine craft

Abstract: This paper investigates formation control of a fleet of ships. The control objective for each ship is to maintain its position in the formation while a (virtual) Formation Reference Point (FRP) tracks a predefined path. This is obtained by using vectorial backstepping to solve two subproblems; a geometric task, and a dynamic task. The former guarantees that the FRP, and thus the formation, tracks the path, while the latter ensures accurate speed control along the path. A dynamic guidance system with feedback from the states of all ships ensures that all ships have the same priority (no leader) when moving along the path. Lyapunov stability is proven and robustness to input saturation is demonstrated using computer simulations.

Method and system for distributed navigation and automated guidance

Abstract: The present invention provides for distributed navigation and route guidance using networked computing devices. A computing device may host one or more navigation functional components (103, 105, 106, 107, 108, and 109). The location of a navigable object (101) is sensed and communicated to associated navigation components in a communication network. The navigation component (103, 105, 106, 107, 108, and 109) collectively provide guidance information to a navigable object controller (102) A navigable object controller (102) interacts with the distributed navigation system through an interface (105), which provides the appropriate presentation of guidance information and functions for the particular type of navigable object controller (e.g. human-machine interface, or system to system). The present invention provides the structures and methods for a flexible navigation and guidance system supporting a variety of network capabilities and computing devices using the same software implementation.

Automatic Guidance of a Farm Tractor Relying on a Single CP-DGPS

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.

Time-Varying Linear Pursuit-Evasion Game Models with Bounded Controls

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.

Circular navigation guidance law for precision missile/target engagements

Abstract: Presents a precision guidance law with impact angle constraint for a two-dimensional planar intercept. It is based on the principle of following a circular arc to the target, hence the name "circular navigation guidance" (CNG). This law is shown mathematically to be successful over a wide range of initial conditions. Computer simulations show that CNG performs much better than an equivalent law from the literature, and that it outperforms the standard proportional navigation guidance law in terms of miss distance. A simplified law is presented that can be used without range-to-target information.

Route guidance system, information delivery center, and vehicular route guidance apparatus

Abstract: An information center generates packets of route guidance information, each corresponding to a prescribed road length of a recommended route. The information center may generate major guide point information and guidance information and transmit both to a vehicular apparatus. The vehicular apparatus provides guidance only for major guide points based on the received major guide point information if it cannot receive the guidance information. According to another aspect of the invention, if the end of a route segment which was the subject of the preceding route guidance information is on an expressway or toll road, guidance information for a preliminary route from that end to an escape position ahead on the expressway or toll road is first transmitted and then information for a remaining route, that is a segment of the recommended route having the prescribed road length minus the preliminary route, is then transmitted. If communication with the information center is lost, the vehicular apparatus performs guidance for the preliminary route to an interchange, for example, of the expressway using the preliminary route guidance information.

Simulation and flight control of an aeroelastic fixed wing micro aerial vehicle

Abstract: Micro aerial vehicles have been the subject of continued interest and development over the last several years. The majority of current vehicle concepts rely on rigid fixed wings or rotors. An alternate design based on an aeroelastic membrane wing has also been developed that exhibits desired characteristics in flight test demonstrations, competition, and in prior aerodynamics studies. This paper presents a simulation model and an assessment of flight control characteristics of the vehicle. Linear state space models of the vehicle associated with typical trimmed level flight conditions and which are suitable for control system design are presented as well. The simulation is used as the basis for the design of a measurement based nonlinear dynamic inversion control system and outer loop guidance system. The vehicle/controller system is the subject of ongoing investigations of autonomous and collaborative control schemes. The results indicate that the design represents a good basis for further development of the micro aerial vehicle for autonomous and collaborative controls research.

Vehicle guidance software, method and system

Abstract: The present invention relates to vehicle guidance software for use with an agricultural vehicle having a guidance system. The software includes a processing portion ( 24 ) for generating a set of guidance indicators from a set of waypoints. The software further includes an adapting portion ( 26 ) for analyzing the guidance indicators produced by the processing portion ( 24 ) and determining whether the guidance indicators define a path that cannot be traversed by the vehicle due to its minimum turning radius. In the event that a path cannot be traversed by the vehicle the adaptive portion ( 26 ) generates a set of alternative guidance indicators that define a path that is traversable by the vehicle.

Towards Active Machine-Vision-Based Driver Assistance for Urban Areas

Abstract: Currently available driver assistance systems (i) warn the driver based on vehicle state sensors (e.g., door open, outside temperature near or below the freezing point), (ii) offer route guidance information (navigation systems based on GPS and digital road maps), or—in some critical situations—(iii) even actively influence vehicle handling under carefully delimited conditions (anti-blocking-system, electronic-stability-program). This contribution reports about investigations to combine passive GPS- and map-based route guidance with model-based machine vision in order to automatically assess or even execute driving maneuvers in inner-city traffic situations. Information provided by todays route guidance systems is treated as a generic description of lane structure. The schematic description of lane structures extractable from commercially available standard digital maps is automatically instantiated by a machine vision approach which interprets video image sequences recorded by cameras from within a driving vehicle. The resulting model of the lane structure in front of the vehicle is subsequently exploited in order to control vehicle maneuvers in real-time as a proof of principal system competences. The machine-vision-based execution of driving maneuvers can at any time be overridden by the driver.

Guidance Law Design by Adaptive Fuzzy Sliding-Mode Control

Abstract: This paperproposes three fuzzy-logic-basedcommandsto line-of-sightguidance laws. Theprinciple of command to line-of-sight guidance is to force a missile to  y as close as possible along the instantaneous line of sight joining the ground tracker and the target. First, the fuzzy logic control and the fuzzy sliding-mode control guidance laws are presented. In addition, an adaptive fuzzy sliding-modecontrol designmethod is developed and is applied for the command to line-of-sight guidance law design. In the design of the adaptive fuzzy sliding-mode control guidance law, the adaptive laws based on a Lyapunov function are developed to adjust the parameters of the fuzzy rules and the uncertainty bound. Thus, the stability of the system can be guaranteed. Finally, two engagement scenarios are examined and a comparison between the proposed fuzzy logic control guidance law, fuzzy sliding-mode control guidancelaw,adaptivefuzzy sliding-modecontrolguidancelaw,andamodel-basedfeedback linearizationguidance law is made.

Destination guidance system and method for generating individually tailored routes within a complex structure

Abstract: This invention is directed to a destination guidance system for providing presentation information that contains guidance pertaining to movement from a place of departure to a destination on the basis of structure information and guidance information on the premises of a building or construction. The presentation information contains both information of the entire three-dimensional structure, and detailed information, and a three-dimensional movement and normal two-dimensional movement in the presentation information are presented by different methods. Also, this invention is directed to a destination guidance data acquisition system for acquiring structure information and guidance information on the premises of a building, which are used by the destination guidance system. The destination guidance data acquisition system inputs and compiles information of a three-dimensional structure on the basis of a plan view of the building to support acquisition of the detailed information.

Software safety analysis of a flight guidance system

Abstract: An aircraft's flight control system provides the capability to stabilize and control the aircraft. Two key elements of a flight control system are the flight guidance system that generates guidance commands and the auto-pilot that executes them. The flight guidance system is a software function composed of flight control laws, that determine the roll and pitch values needed to achieve the desired flight characteristics, and mode logic that selects the appropriate flight control law for the given situation. We developed a formal, executable model of the requirements for the mode logic of a flight guidance system and conducted a comprehensive software safety analysis on the model. We provide an overview of the safety analysis conducted on the software and summarize progress made to date in the use of formal methods to verify the presence of the required safety properties in the software itself.

Factors in Productivity and Unit Cost for Advanced Machine Guidance

Abstract: This paper presents an initial step in seeking to understand just how the adoption of advanced machine guidance technology, especially global positioning systems, leads to improvements in performance by the earthwork contractor. Two grading scenarios and one dozing scenario are examined based upon site observations and interviews with field personnel. Analysis demonstrated that productivity and unit cost improvements result from a reduction in surveying support, grade checking, an increase in operational efficiency, and a decrease in the number of passes. These results are in agreement with published results of benefits of 3D guidance over 2D guidance.

Destination guidance system, destination guidance server, user terminal, destination guidance method, computer readable memory that stores program for making computer generate information associated with guidance in building, destination guidance data acquisition system, destination guidance data acquisition server, destination guidance data acquisition terminal, destination guidance data acquisition method, and computer readable memory that stores program for making computer acquire data associated with guidance in building

Abstract: This invention is directed to a destination guidance system for providing presentation information that contains guidance pertaining to movement from a place of departure to a destination on the basis of structure information and guidance information on the premises of a building or construction. The presentation information contains both information of the entire three-dimensional structure, and detailed information, and a three-dimensional movement and normal two-dimensional movement in the presentation information are presented by different methods. Also, this invention is directed to a destination guidance data acquisition system for acquiring structure information and guidance information on the premises of a building, which are used by the destination guidance system. The destination guidance data acquisition system inputs and compiles information of a three-dimensional structure on the basis of a plan view of the building to support acquisition of the detailed information.

Common interface architecture for horizontal directional drilling machines and walk-over guidance systems

Abstract: A system and method of interfacing a drilling machine with one of a number of different walk-over guidance systems involves receiving an ID signal from a particular walk-over guidance system selected for use with the drilling machine. A protocol library associated with the particular walk-over guidance system is accessed in response to the ID signal. The protocol library is used to effect communication between the particular walk-over guidance system and a control system of the drilling machine during cooperative use of the particular walk-over guidance system and drilling machine. Using the protocol library involves converting, as prescribed by the protocol library, locator signals received from the particular walk-over guidance system from a locator protocol to a common protocol used by the control system of the drilling machine. Locator and drilling machine data of various types can be presented to a drilling machine operator via an on-board display.

A Method of Evaluating Different Guidance Systems

Abstract: Knowing the accuracy of the many different guidance systems available on the market is of concern to growers and farmers who own, rent, or are considering purchasing one of these systems. This paper outlines the issues that need to be considered in comparing the accuracy of different guidance systems. Also, it introduces a method of evaluating and comparing the accuracy of different guidance systems. Six commercially available guidance systems were evaluated for overall performance in a series of field tests. All systems used WAAS as a source of differential signal. The data collected was evaluated by examining the mean error and standard deviation of error calculated from the differences in actual position of the tractor in field relative to the calculated (desired) position. The results indicate that with the exception of two systems, the accuracy of guidance systems on the straight line are not significantly different from each other.

Precision-guided hypersonic projectile weapon system

Abstract: A precision-guided hypersonic projectile weapon system. The inventive system includes a first subsystem for determining a target location and providing data with respect thereto. A second subsystem calculates trajectory to the target based on the data. The projectile is then launched and guided in flight along the trajectory to the target. In the Illustrative application, the projectile is a tungsten rod and the first subsystem includes a forward-looking infrared imaging system and a laser range finder. The second subsystem includes a fire control system. The fire control system includes an optional inertial measurement unit and predicts target location. The projectile is mounted in a missile launched from a platform such as a vehicle. After an initial burn, the missile launches the projectile while in flight to the target. The missile is implemented with a rocket with a guidance system and a propulsion system. In accordance with the present teachings, the guidance system includes a transceiver system mounted on the projectile. The transceiver system includes a low-power continuous wave, millimeter wavelength wave emitter. A system is included at the launch platform for communicating with the projectile. The platform system sends a blinking command to the projectile and measures the round trip delay thereof to ascertain the range of the projectile. Velocity is determined by conventional Doppler techniques or differentiation. Azimuth and elevation are then determined by a monopulse antenna on the launch platform. As a consequence, the platform ascertains the location of the projectile and the impact point thereof. The platform generates a command to the projectile which is received by the projectile and used to actuate control surfaces to adjust the trajectory and impact point thereof as necessary.

AIAA 2002-4875 Simulation and Flight Control of an Aeroelastic Fixed Wing Micro Aerial Vehicle

Abstract: Micro aerial vehicles have been the subject of continued interest anddevelopment over the last several years. The majority of current vehicleconcepts rely on rigid fixed wings or rotors. An alternate design based on anaeroelastic membrane wing has also been developed that exhibits desiredcharacteristics in flight test demonstrations, competition, and in prioraerodynamics studies. This paper presents a simulation model and anassessment of flight control characteristics of the vehicle. Linear state spacemodels of the vehicle associated with typical trimmed level flight conditionsand which are suitable for control system design are presented as well. Thesimulation is used as the basis for the design of a measurement based nonlineardynamic inversion control system and outer loop guidance system. Thevehicle/controller system is the subject of ongoing investigations ofautonomous and collaborative control schemes. The results indicate that thedesign represents a good basis for further development of the micro aerialvehicle for autonomous and collaborative controls research.IntroductionMicro aerial vehicles, or “MAVs”, are typicallydesignated as a class of aircraft with a maximumdimension of 6 inches that are capable of operating atspeeds of 25 mph or less.

Waypoint-based Fuzzy Guidance for Unmanned Aircraft - A New Approach

Abstract: The paper presents the development and the simulation results of a GPS-based waypoints Fuzzy Guidance System (FGS). Waypoints are described in a 5-dimensional space: position in 3-dimensions plus desired crossing heading and velocity. The aircraft is assumed to be autopiloted in velocity, heading and flight path angle. The FGS is based on three standard Takagi-Sugeno1 fuzzy controllers that generate separately velocity, heading and flight path angle references for the autopilots. Simulation results show that, under the fuzzy guidance, the aircraft correctly crosses all waypoints in the specified sequential order. The FGS handles a non-flyable waypoints set as well, driving the aircraft on flyable trajectories that try to cross the waypoints at the prescribed altitude and with prescribed heading.

Nonlinear Guidance and Navigation of a Tactical Missile with High Heading Error

Abstract: This study examines the guidance and navigation problem of an acceleration constrained tactical missile for any initial missile and target orientation. A nonlinear guidance law (NGL) based on the theory of nonlinear differential geometric methods is presented, and an extended Kalman filter (EKF) in modified spherical coordinate (MSC) has been invoked for the third party (tracking radar) to estimate the missile-to-target position, velocity, and acceleration before handing over. After locking on the target, the RF seeker of the missile is used to estimate the required guidance information using active seeker measurements. It can be shown that the design of the guidance algorithm valid for arbitrary initial missile and target orientation in three dimension (3-D) has to null not only the line of sight (LOS) rate but also the relative heading error (RHE). The performance of a tactical missile with an active RF seeker in high relative heading error (RHE) is evaluated using the combination of an EKF and the NGL in two dimension (2-D) space. In particular, a comparison is made between two guidance schemes using estimated states from an EKF. The two guidance schemes are 1) a composite NGL coupled with a terminal side jet control (TSJC), and 2) a traditional extended proportional navigation (EPN) guidance law also coupled with the TSJC. The results show that the composite NGL coupled with a TSJC provides a significant improvement in high RHE engagements over the traditional PN type guidance law.

Evolved SeaSparrow Missile Jet Vane Control System Prototype Hardware Development

Abstract: Rapid response to a high-speed, low-altitude, incoming missile imposes very stringent design requirements on an air-defense missile, the Evolved SeaSparrow Missile. A successful solution was devised using a jet vane control system for missile maneuvering during the boost phase of the shipboard vertical launch. By the location aft of the rocket motor nozzle, the vanes are inserted into the propellant stream for the purpose of generating maneuvering forces. After rocket motor burn out, the jet vane assembly detaches from the missile and falls away to not degrade the rocket motor specie c impulse during e ight to target. The four vanes are mounted at right angles to each other with each having its own mounting support and geartrain assembly. Each vane is connected through a detachable coupling to the steering control system of the missile, such that actuation of the steering control simultaneously actuates the jet vanes. The Evolved SeaSparrow Missile consortium successfully designed, analyzed, prototype developed, and e ight tested a jet vane control prototype and has implemented the design into the program. Empirical test data were found to correlate well with the analytical techniques used to predict vane performance and resulted in a system capable of meeting the missile operational requirements.

Pedestrian guidance system, pedestrian guidance method, and traveling direction information generation program

Abstract: PROBLEM TO BE SOLVED: To provide a pedestrian guidance system having a low arrangement cost, capable of guiding a pedestrian by presenting the correct traveling direction along a route to the destination, a pedestrian guidance method and a pedestrian guidance program. SOLUTION: When receiving ID data originated from radio tags 2 arranged at optional intervals capable of receiving the ID data of of one or more radio tags 2 and acquiring destination information inputted by the pedestrian, a portable terminal 3 transmits the newest received ID data, received ID data before one point of time, and the destination information. A location processing device 4 deduces the present traveling direction of the pedestrian carrying the portable terminal 3 by retrieving database based on the information, performs generation/setting of the route to the destination from the present position of the pedestrian, and generates and transmits traveling direction information from the present position to the destination. The portable terminal 3 presents the received traveling direction information to the destination to the pedestrian. COPYRIGHT: (C)2004,JPO

Vehicle guidance software, method and system

Abstract: The present invention relates to vehicle guidance software for use with an agricultural vehicle having a guidance system. The software includes a processing portion ( 24 ) for generating a set of guidance indicators from a set of waypoints. The software further includes an adapting portion ( 26 ) for analysing the guidance indicators produced by the processing portion ( 24 ) and determining whether the guidance indicators define a path that cannot be traversed by the vehicle due to its minimum turning radius. In the event that a path cannot be traversed by the vehicle the adaptive portion ( 26 ) generates a set of alternative guidance indicators that define a path that is traversable by the vehicle.

Automatic division of traffic control sub-area under condition of route guidance

Abstract: To implement final integration of route guidance system and traffic control system,much research need to be done.One problem is how to realize data share and coordination between the route guidance system and the real time traffic control system,such as SCAT,SCOOT etc.This paper intends to discuss how the two systems use share data to perform automatic division of traffic control sub area under condition of route guidance. 2 figs,3 refs.

Variable structure based nonlinear missile guidance and autopilot design for a direct hit with thrust vector control

Abstract: In this paper, we propose a variable structure based nonlinear missile guidance and autopilot systems for a direct hit with thrust vector control and divert control system inputs for the interception of a ballistic missile. The aim of the present work is to achieve the bounded target interception of the missile such that the distance between the missile and the target is close enough to trigger the missile's explosion. First, a 3 degree-of-freedom (DOF) sliding mode missile guidance law under considering external disturbances and zero-effort-miss (ZEM) are designed to minimize the distance between the missile and the target for the translation motion. Then, we proposed a quaternion-based sliding-mode attitude controller to track the attitude command and to cope with the effects from variations of missile's inertia, aerodynamic force and wind gusts. The exponentially stability of the overall system is analyzed thoroughly via Lyapunov stability theory before entering ZEM phase. Extensive simulation results are conducted to validate the effectiveness of the proposed integrated guidance law and autopilot system by use of the 5-DOF inputs.

Route guidance system

Abstract: PROBLEM TO BE SOLVED: To provide a route guidance system for appropriately guiding a route by considering the type of a vehicle, a movement means such as walking and a bicycle other than an automobile, and the performance or restrictions on the behavior of the movement means, a user, or the like SOLUTION: In a search condition memory 9, a search condition table is prepared In the search condition table, various consideration conditions are recorded for each type of the movement means, behavior performance, or restriction In a map information memory 5, a road information table is prepared In the road information table, many kinds of peculiar and dynamic information are recorded for each section where the path is divided into pluralities of sections The map information memory 5 is updated as required When the user inputs the type, behavior performance, or restriction of the movement means to be used, the route that is from a current location to a destination, and is suitable for the consideration conditions due to the movement means or the like is searched for indicating to the user

Application of fiber gyros at MPC - Inertial Navigation and Guidance system for M-V rocket

Abstract: The Inertial Navigation and Guidance system (ING) with fiber gyros (FOGs) was developed for the ISAS (Institute of Space and Astronautical Science) M-V rocket. The M-V-1 rocket was successfully launched in February 1997. A series of M-V rockets was launched three times and FOG-INGs worked well in all flights. This paper presents the breakthrough points with the flight data of M-V-1 rocket's ING.

Laser semiactive guidance method and laser semiactive guidance system

Abstract: PROBLEM TO BE SOLVED: To provide a laser semiactive guidance system allowing the improvement of hit precision in missile guidance or the like and the reduction in laser irradiation load on a pointing side. SOLUTION: A laser irradiator 3 controls the beam width of a laser beam irradiated to a target 2 so as to narrow in the early or middle guidance after launching of a missile 1 and extend in the end guidance where the missile 1 approaches the target 2. The missile 1 tracks the laser spot of the target in the early or middle stage of launching and determines, after the beam width of the laser beam is extended to detect the image of the whole shape of the target, the hit point in the image by itself to track it.