Showing papers on "Guidance system published in 1985"

Line-of-sight reconstruction for faster homing guidance

Abstract: A novel way to generate the signal required for homing guidance is to reconstruct the line of sight angle by combining seeker boresi ht error with an integrated rate gyro signal (1.2,3,1,5). The paper shows that line-of-sight (LQS) reconstruction allows reduced stabilization loop gain requirements over other guidance implementations. For a given stabilization loop gain, faster guidance system time constants can be achieved with LQS reconstruction, thus enabling the guidance system to achieve more accurate hominq than other implementations.

A Stochastic Approach for Estimating the Effectiveness of a Route Guidance System and Its Related Parameters

Abstract: Mathematical models are developed for estimating the effectiveness of a route guidance system (RGS) in which the control strategy is to guide vehicles toward the shortest travel time routes. These models are formulated by considering the stochastic nature of travel time. The parameters which characterize the models are defined and a quantitative analysis of the models is given for various values of the parameters. It is shown that the effectiveness of RGS can be estimated by the number of nodes along the route. The results derived from the models are shown to agree with experimental data collected from a route guidance system constructed in Tokyo. Some practical applications of the results are discussed.

Control device for a vehicle route guidance system

Abstract: A control device of a component vehicle route guidance system, the system comprising an on-board section having a navigation computer, and a vehicle-installed display for indicating the driver information data of the system. The control device is constructed as a portable hand-operated unit including a route computer, operating means and its own display, allowing the preselection of the route functions to be performed outside the vehicle. The device interfaces with the guidance system by plugging it into the on-board section in the vehicle. Various functions are enabled depending on which position the control device occupies in the on-board section.

Fiber optic track/reaim system

Abstract: In a missile tracking and guidance system, a fiber optic link is maintained between a missile and the launcher. Tracking after launch is via a video link between the missile seeker and a video imager at the launcher. Guidance signals are derived from the video signal input to the imager and transmitted back to the missile. Additionally, rate sensors and an interrupt or reaim circuit within the launcher allows an operator to reacquire the target for refining the missile seeker look axis toward a target during flight. After the target aimpoint is refined the operator can then release the interrupt circuit, allowing the system to continue tracking from the video input, with a newly established seeker heading established during the aimpoint refinement.

Electronic image stabilization

Abstract: In an optical guidance system, body fixed electronic image stabilization of television imaging is used to allow strapdown seeker guidance in a missile. Electronic image stabilization eliminates the need for a stabilized sensor or seeker platform while providing the same line-of-sight information that would have been obtained from the platform. Body fixed electronic image stabilization compensates for routine vibrational and rotational motion experienced by a missile airframe during flight. This compensation is accomplished by deliberately underscanning the camera and driving the camera's deflection coils with signals from pitch and yaw body rate sensors on the missile. The image developed on the camera detector raster is thereby moved in an equal and opposite direction to the sensed, experienced, motion during the same instant that the motion is occuring. Compensation thus stabilizes the resultant image, which would otherwise be a blur of motion on the display screen.

Helmut Hoelzer's Fully Electronic Analog Computer

Abstract: A fully electronic general-purpose analog computer was designed by Helmut Hoelzer, a German electrical engineer and remote-controlled guidance specialist. He and an assistant built the device in 1941 in Peenemunde, Germany, where they were working as part of Wernher von Braun's long-range rocket development team. The computer was based on an electronic integrator and differentiator conceived by Hoelzer in 1935 and first applied to the guidance system of the A-4 rocket. This computer is significant in the history not only of analog computation but also of the formulation of simulation techniques. It contributed to a system for rocket development that resulted in vehicles capable of reaching the moon.

Ground based concept for time control of aircraft entering the terminal area

Abstract: This paper summarizes current research for increasing the efficiency of traffic flow at hub airports by application of four dimensional (4D) guidance techniques. A method for generating 4D guidance commands to control the landing time of aircraft that are not equipped with on-board 4D guidance systems is described. In one possible implementation the commands are generated in an auxiliary processor linked to the ATC host computer and displayed on a controller's monitor in the form of profile descent advisories. Accurate time control is achieved by generating air traffic controller advisories in a ground-based algorithm that combines aerodynamic, thrust and atmospheric models with an efficient numerical integration method. The time accuracy and fuel efficiency achieved when the pilot responds to these advisories were evaluated in a piloted simulation of a transport aircraft.

Digital Homing Guidance—Stability vs Performance Tradeoffs

Abstract: Digital signal processing capability can be added to a missile homing guidance system to provide a broad system decision capability against a complex threat. This processing may be on the ground or in the missile. Wherever it occurs, it introduces additional dynamics into the guidance loop which can degrade system performance. In fact, the influence of digitization is so important that it must be included at the outset in order to ensure that a guidance system design will work. One of the most significant effects is the introduction of a sample and hold in the guidance attitude loop. This paper discusses the influence of digital processing on system relative stability and performance. A variety of techniques for improving system performance are introduced and tradeoff curves are presented indicating how major subsystem parameters, such as seeker stabilization loop gain or autopilot time constant, may be specified. The results show the tradeoffs between a robust set of guidance subsystem specifications and acceptable performance when digital guidance is used.

Laser beam rider guidance utilizing beam quadrature detection

Abstract: A beam rider guidance system is presented which uses a rotating laser light pattern to enable a weapon-borne laser receiver to derive its position relative to the beam axis. The guidance beam consists of changing light patterns detected and decoded by the receiver as a guidance code, which defines the unique weapon position in the beam. The code is composed of four distinguishable patterns of light bars which can be detected and decoded into electrical pulses by the laser receiver located anywhere within the confines by the guidance beam.

Help guidance system

Abstract: PURPOSE: To improve the operability with a help guidance system by giving the definite explanation to the contents requested by a user. CONSTITUTION: A guidance request code supplied from an input part 1 is applied to an internal storage part 3 and the guide information is displayed at an output part 2 after the guide information and a correspondence table are read out of an external storage part 4. If an indefinite part is included in each word of the explanation, a user points out the area where the guidance is needed. Thus the position information is delivered to a guide control function part. Then the guidance position is detected on a picture and the corresponding item is detected by means of the correspondence table. Thus the guidance explanation is displayed. COPYRIGHT: (C)1987,JPO&Japio

Controller for vehicle destination indication system

Abstract: A control device of a component vehicle route guidance system, the system comprising an on-board section having a navigation computer, and a vehicle-installed display for indicating the driver information data of the system The control device is constructed as a portable hand-operated unit including a route computer, operating means and its own display, allowing the preselection of the route functions to be performed outside the vehicle The device interfaces with the guidance system by plugging it into the on-board section in the vehicle Various functions are enabled depending on which position the control device occupies in the on-board section

Applicability of guidance and navigation systems (abridgment)

Abstract: Vehicle location, guidance, and navigation systems of varying degrees of complexity are receiving increasing attention in an attempt to reduce adverse energy consumption safety, and environmental effects of excess travel as a result of navigational failures. The various systems advocated or proposed apply to different types of travel as described by trip length, trip purpose, driver demographic characteristics, and other factors. The National Personal Transportation Study data base was analyzed to determine the distribution of a number of pertinent variables. These data are presented and examples are provided of how the results of this analysis can be used to determine the applicability of specific system configurations.