Showing papers on "Guidance system published in 1982"

Guidance method and system for an automotive vehicle

Abstract: A guidance method and system for an automotive vehicle which switches from an electronic navigational signal method to a dead reckoning method when any of the field strengths of three navigational electromagnetic wave signals drops below a predetermined lower limit or vice versa when the field strengths of the three navigational electromagnetic wave signals all exceed the lower limit. Therefore, even if the navigational wave signals are obstructed by buildings or mountains, it is possible to continuously determine and display the vehicle position. The guidance system according to the present invention comprises a receive-state detection unit for detecting three field strengths and for comparing the detected field strengths with a predetermined lower limit, and a selector for selectively outputting vehicle position signals on the basis of navigational signals or dead reckoning, in addition to the conventional electronic navigation system and dead reckoning system.

Space guidance evolution - A personal narrative

Abstract: Introduction T prospect of preparing a comprehensive history of space guidance and navigation was, initially, a delight to contemplate. But, as the unproductive weeks went by, the original euphoria was gradually replaced by a sense of pragmatism. I reasoned that the historical papers which had the greatest appeal were written by "old timers" telling of their personal experiences. Since I had lived through the entire space age, and had the good fortune of being involved in many of the nation's important aerospace programs, I decided to narrow the scope to encompass only that of which I had personal knowledge. (It is, however, a sobering thought that you might qualify as an ' 'old timer.") The story begins in the early 1950's when the MIT Instrumentation Laboratory (later to become the Charles Stark Draper Laboratory, Inc.) was chosen by the Air Force Western Development Division to provide a self-contained guidance system backup to Convair in San Diego for the new Atlas intercontinental ballistic missile. The work was contracted through the Ramo-Wooldridge Corporation, and the technical monitor for the MIT task was a young engineer named Jim Fletcher who later served as the NASA Administrator. The Atlas guidance system was to be a combination of an on-board autonomous system, and a ground-based tracking and command system. This was the beginning of a philosophic controversy, which, in some areas, remains unresolved. The self-contained system finally prevailed in ballistic missile applications for obvious reasons. In space exploration, a mixture of the two remains. The electronic digital computer industry was in its infancy then, so that an on-board guidance system could be mechanized only with analog components. Likewise, the design and analysis tools were highly primitive by today's standards. It is difficult to appreciate the development problems without considering the available computational aids.

Optimal control and estimation for strapdown seeker guidance of tactical missiles

Abstract: M contemporary tactical guided weapons utilize proportional navigation as the terminal guidance law and an jnertially stabilized gimballed seeker to provide guidance information. The proportional guidance law is most often used because it can be easily implemented. It has been shown that proportional navigation is most effective under restrictive engagement conditions, i.e., small off-boresight angle launches, intercepting low-maneuverability targets; however, when employed in engagements that deviate from these conditions, proportional navigation's performance is degraded. Inertially stabilized gimballed seekers, which track the target, have been used in the past because of field-of-view limitations, physical implementation requirements to maintain seeker lock-on, and the practical consideration that this method provides the most direct means of obtaining the required inertial line-of-sight rates necessary for proportional navigation.

Automatic flight control with pilot fly-through

Abstract: A system and technique is disclosed which enables an aircraft to naturally respond to pilot inputs during automatic flight control of aircraft attitude or course and to smoothly return to that attitude or course following pilot maneuvers. The aircraft attitude control channels of an aircraft control system are held at a predetermined attitude reference by an automatic flight control system or programmed to follow a particular navigational course by a flight director guidance system. The aircraft control stick is coupled to disconnect the predetermined pitch and roll attitude from flight control following a stick movement of a predetermined distance or the application of a predetermined force to the stick so that the AFCS or flight director guidance system no longer attempts to hold the set attitude or navigational course. The control stick commands an angular rate of change proportional to the magnitude of the pilot's stick displacement or force. Upon release of the force and return of the aircraft control stick to a neutral position, a "fly through" fading circuit smoothly returns the aircraft to its original attitude or navigational course.

Fourth order predictive, augmented proportional navigation system terminal guidance design with missile/target decoupling

Abstract: A method for augmenting a noise-adaptive predictive proportional navigation terminal guidance scheme. In a fourth order configuration with noise adaptive varying gain parameters calculated as a function of time-to-go, this system implements an optimal control law to augment proportional navigation with target and missile information terms and a navigation ratio which is a function of time-to-go. By employing a fourth order system, enhanced use may be made of information already available in the guidance computer and missile control system to decouple target motion information from the missile control signals. Decoupled target motion information facilitates blind-mode operation in the end game, the last few seconds before intercept. Decoupled missile control information enables the airframe to be controlled to predefined orientations for aimed warhead applications. This system is particularly useful for high and medium altitude targets and results in significant miss distance improvement for terminal guidance against small maneuvering targets. The system has additional benefits in that it results in nearly optimal miss distance behavior with sensitivity to unmodeled errors being substantially less than that in modern guidance systems.

Adaptive noise estimation and guidance for homing missiles.

Abstract: The presence of a microprocessor makes it possible to utilize a digital filter to process the measurement data and obtain a state estimate to be used in a digital guidance system for tactical homing missiles. Of particular interest is the case of the short range, air-to-air missile against a highly maneuverable target when angleonly measurements are available. Two schemes are proposed which improve the homing performance. The first is an extended Kalman filter with the adaptive feature of estimating the measurement variance on line. The second is an adaptive guidance scheme based on an exponential cost function which is used in conjunction with the filter.

Noise-adaptive, predictive proportional navigation (NAPPN) guidance scheme

Abstract: A method for augmenting the value of range uplink information in a predictive proportional navigation terminal guidance scheme. A second order configuration, with noise adaptive varying gain parameters calculated as a function of time-to-go, is particularly useful for high altitude, minimally maneuvering targets. This configuration results in acceptable miss distances, better than conventional proportional navigation, with sensitivity to unmodeled errors being substantially less than that in modern guidance systems. A third order configuration makes enhanced use of range uplink information to provide improved terminal guidance against lower altitude maneuvering targets. The sensitivity of the third order configuration is similar to that of conventional proportional navigation but with better miss distance results.

Autonomous Rendezvous and Docking

Abstract: A number of future space missions will require autonomous rendezvous and docking of spacecraft. Recent work in video guidance shows that a video approach has great promise for solving problems in close-in operations, especially where operation with multiple target spacecraft is required. A video guidance system can be built with existing processor and sensor technology. This paper presents approaches and design constraints for such a system.

Automatic vehicle guidance — Commanded map routing

Abstract: This paper presents a proposed experimental system for automatic vehicle guidance commanded by a written route on map The system is a kind of vehicleborne location and guidance system controlled by self-contained dead-reckoning computer The location and heading of a vehicle are essentially computed from the angular velocities of the both wheels The steering system is operated by comparing the forecast position, heading and velocity with route on map The experimental results using a small car show the good accuracy and performance of this system

Seeker-body decoupling system

Abstract: An improved airframe body decoupling system for a body gimballed sensor on an interceptor aircraft or guided missile. Body rate gyro information is employed for internal decoupling so as to eliminate decoupling match sensitivity to receiver errors. The true measure of sensor position from the gimballed antenna potentiometer is differentiated and then externally decoupled to produce the desired line-of-sight rate for use by the guidance/control section of the proportional navigation guidance system.

The impact of microtechnology: A case for reassessing the roles of computers in learning

Abstract: Recent advances in microtechnology will have a significant impact on both Computer Aided Learning and Instruction. They will enable cheap systems to be configured for use in learning situations and will provide a sound basis for improved interface design. This paper first reviews the changes that have taken place and concludes that distributed systems based on standard network technology will become widespread and a new generation of users will emerge who are unskilled in computing and remote from professional advice. The system itself will have to provide guidance. Advances in Computer Aided Learning and Instruction and the work on Expert Systems in Artificial Intelligence will provide a basis for the design of guidance systems which the paper groups under the term Computer Aided Guidance. Such systems will have short-term goals and will be economically justifiable. The paper suggests that workers in Computer Aided Learning and Instruction should contribute to this new field of activity.

Device to spatially encode a beam of light

Abstract: A guidance system for a beam rider missile, having a novel coded light beam projector at an aiming station, for use by a missile-mounted receiver. The projecting means contains a rotating transparent reticle through which the beam is transmitted, the reticle having an opaque radial portion in a curved "leaf" shape. When the diameter of the projected beam is held constant at the missile distance during flight, the position of the missile in polar coordinate form is given by the relative angular position and duration of the blocked-out portion of the beam received at the missile.

Course guidance system

Abstract: In a course guidance system for use in an automobile, for example, which includes an electronic display, a map, a direction sensor, a speed sensor and the like for deriving the present location of the car and plotting it on the display, the invention provides a course guidance system for a car which causes a linear and/or rotational movement of the driving locus displayed on the display when the map is changed or reset so that the present position can be easily located on the map.

Performance and effectiveness of route guidance systems

Abstract: Presents an "ex post" benefit cost analysis of the Rhein/Main route guidance system, based on a detailed analysis of its performance.

Voice guidance system

Abstract: PURPOSE:To reduce unnecessary voice guidance to a skillful customers, by displaying the content of desired display through a display means and making the voice guidance corresponding to the content of display afer a prescribed time. CONSTITUTION:A display means 1 visually displaying a guidance to the user for an automatic deposition payment device, voice guidance means 13 for voice guidance, selecting means selecting the content of display by the means 1, and the selecting means selecting the content of guidance with the voice guidance means 13, are provided. The content of display is corresponded to the content of voice guidance, and after displaying a desired display content with the display means 1, the voice guidance corresponding to the content of display by the means 1 is made with the voice guidance means 13 after a prescribed time t.

Optimal Terrain-Following Feedback Control for Advanced Cruise Missiles

Abstract: : A cruise missile is a vehicle that spends the major portion of its flight at essentially constant altitude and speed. Some cruise missiles are flown at very low altitudes in order to avoid detection. The terrain-following capabilities of such a missile and its guidance system are of importance. It is desirable that the missile should follow closely the contour of the terrain, which may be fixed (Land) or time-varying (ocean waves). A previous study (Ref. 1) demonstrated that optimal control theory could usefully be applied to calculate the best achievable accuracy of terrain-following. Reference 1 showed that, even with an optimal guidance system, terrain-following accuracy was limited by considerations of the cruise missile's inertias, airspeed, and aerodynamic configuration.

Adaptive noise estimation and guidance for homing missiles

Abstract: The presence of a microprocessor makes it possible to utilize a digital filter to process the measurement data and obtain a state estimate to be used in a digital guidance system for tactical homing missiles. Of particular interest is the case of the short range, air-to-air missile against a highly maneuverable target when angleonly measurements are available. Two schemes are proposed which improve the homing performance. The first is an extended Kalman filter with the adaptive feature of estimating the measurement variance on line. The second is an adaptive guidance scheme based on an exponential cost function which is used in conjunction with the filter.

The Joint Cruise Missiles Project: An Acquisition History--Appendixes

Abstract: : These appendices provide additional details of project organization and management procedures to the main report These appendixes include: Joint Cruise Missiles Project Office Evolution; DMA/JCMPO Interaction; Cruise Missile Test Program; ALCM competitive Flyoff; Sustainer Engine Production Competition; Production; Cruise Missile Land-Attack Guidance System; Warranties; and Program Costs

An economical and flexible alternative orbital transfer vehicle

Abstract: This paper describes a study to determine the characteristics and costs of an all-liquid low-thrust propulsion module to replace the Inertial Upper Stage (IUS) as a means for obtaining geosynchronous orbit (GEO). The propulsion module proposed by TRW is propelled by low-thrust gimballed engines, using storable bipropellants from a multitank pressure-fed system. It mounts in a cradle in the Space Transportation System (STS) Orbiter cargo bay, and provides a platform for integration of spacecraft subsystems and payload mounting. Performance flexibility is obtained as a result of varying propellant capacity by adjusting the length of the cylindrical portion of the propellant tankage. Although the specific impulse of this system is comparable to that obtainable from the IUS solid motors, important gains in performance and cost come from weight savings and equipment reduction. The latter is achieved by avoiding duplication of many functions readily available from the spacecraft that the propulsion module is transporting. The TRW propulsion module concept was applied to transfer a growth version of the Tracking and Data Relay Satellite (TDRS) to GEO. The ground rules for the study permitted no changes to TDRS hardware and maximum utilization of its on-orbit subsystems to assist the propulsion module. A novel guidance system which requires little ground assistance was adopted. The study achieved its aim of proving design feasibility and economy.

Space telescope - The next generation

Abstract: The command handling approach as applied to fine guidance sensor guide star acquisition is described in order to illustrate the flexibility it provides to users of the Space Telescope. User control of pointing operations is detailed, and the pointing control system/fine guidance system interface is depicted along with the guide star acquisition sequence. Reaction wheel interaction with vehicle structural modes and the rate gyro assembly noise level are discussed and some test data are shown.

Route sensor of unmanned vehicle of electromagnetic guidance system

Abstract: PURPOSE:To realize compact constitution by arranging detection coils at a right position and a left position symmetrical to a guidance line. CONSTITUTION:A route sensor is composed by combining two detection coils consisting of a coil 3 crossing a guidance line 10 vertically and a horizontal coil 4 having a slanting angle theta to a road surface and parallel to the guidance line 10 in a horizontal plane, in a T shape. When a guided vehicle is on the guidance line 10, a voltage V4 is induced across the vertical coil 3, but a voltage V3 across the horizontal coil 4 is zero and the terminal voltages V1 and V2 of capacitors C3 and C4 are equal, so that the output of a differential amplifier OP is zero. When the vehicle deviates from the guidance line 10 to right and the coil 4 generates the voltage V3 in phase with the voltage V4 of the coil 3, the output voltage of the differential amplifier OP is positive and when to left, the output voltage is negative, thereby correcting its track through steering motor. Thus, the compact constitution is realized.

Application of image processing to vehicle guidance and safety

Abstract: This report covers the second year of the two-year research contract on the application of image processing to vehicle guidance and safety. The purpose of the research was to establish fundamental system concepts for using machine vision in the control of vehicles and to make feasibility studies on the various technologies involved. The results are aimed towards building experimental hardware for one or more modes of system operation.

Gps instrumentation performance as an icbm guidance system evaluator

Abstract: In early 1980, a four-channel GPS receiver, the M issile Borne Receiver Set (MBRS), was test flown on two Minuteman I11 flight t ests, PVM-18 and PVM-19. These flight tests were part of the Fly-2 flight test series, and each carried two NS20 Inertial Units. The primary objective of these two tests was to demonstrate and determine the performance of GPS in an ICBM missile environment. This paper summarizes the results of the analysis of GPS Performance on these two flights. It demonstrates how data of this quality can provide superior evaluation of total guidance error and can be used to identify inflight guidance anomalies. The GPS data on these flights demonstrated short-term a ccuracy e qual to the predicted levels. Typically random errors on the order of 2 ft. and .O1 ft/sec (for a one-second average) were obtained. T his allowed, for the first time, direct observation of PIGA magnetic sensitivity e ffects during the PBV period by an external sensor. The absolute accuracy was less easily evaluated due to the lack of a suitable standard. GPS was clearly more accurate than the radars that also tracked the m issile, and the post-fit r esiduals are consistent with a high level of total accuracy. It was therefore concluded that total accuracy was consistent with the predicted GPS performance.

A radio guidance algorithm for M Series rockets that are used to launch Japanese scientific satellites

Abstract: A simple radio guidance system was adopted for M Series rockets that are used to launch Japanese scientific satellites, because of its cost performance and for orbital accuracy. In this paper, the basic concepts of the radio guidance system and its algorithm are shown with the flight plan of the rocket. The idea is simple and straightforward. As a consequence, the software is reliable and the capacity of the computer is not exceeded, and yet the guidance system still achieves the required accuracy. The system has been implemented gradually and with success during the last ten launchings. Improved accuracies were realized. In this paper the algorithm is described and several of the resulting trajectories are shown.

Investigation of advanced navigation and guidance system concepts for all-weather rotorcraft operations

Abstract: Results are presented of a survey conducted of active helicopter operators to determine the extent to which they wish to operate in IMC conditions, the visibility limits under which they would operate, the revenue benefits to be gained, and the percent of aircraft cost they would pay for such increased capability. Candidate systems were examined for capability to meet the requirements of a mission model constructed to represent the modes of flight normally encountered in low visibility conditions. Recommendations are made for development of high resolution radar, simulation of the control display system for steep approaches, and for development of an obstacle sensing system for detecting wires. A cost feasibility analysis is included.

An overview of NASA's role in maneuvering missile aerodynamic technology

Abstract: This paper presents an overview of the role NASA has had and continues to pursue in providing missile aerodynamic technology. In the past, NASA has provided considerable support to the missile industry and the military. The support has generally taken the form of theoretical aerodynamic analyses, experimental studies to provide solutions for specific problems, and the documentation of existing foreign missile systems and domestic missiles. In 1975, NASA shifted its missile-related efforts in aerodynamics from this largely service role to one of conducting more basic research. The areas of research include: innovative methods for roll control of cruciform missiles, airbreathing missiles with maneuver requirements, and an advanced generation of monoplanar missiles for efficient supersonic carriage and delivery.