Showing papers on "Guidance system published in 1984"

Ordnance delivery system and method including remotely piloted or programmable aircraft with yaw-to-turn guidance system

Abstract: A method and system for delivery ordnance to a target via a remotely piloted or programmable aircraft including a yaw-to-turn guidance system, a deployment and launching system and packaging for the aircraft are disclosed.

Guided projectile flight control fin system

Abstract: A guidance system for small spinning projectiles which is mechanically simple, has low power requirements, uses relatively unsophisticated electronics, and is capable of withstanding large gas pressures and accelerations. The system uses a one-piece fin assembly which is de-spun so that its guidance fins maintain a constant attitude with respect to the ground. The guidance fins and their hub can be nutated simultaneously and independently in two orthogonal planes by pivoting and translating a single control rod. The hub cooperates with the projectile body to reduce its base drag and thereby extend its range.

Target acceleration modeling for tactical missile guidance

Abstract: For future short-range air-to-air missile concepts, it has been demonstrated that linear optimal guidance laws provide significant performance improvements over proportional navigation guidance laws. This paper addresses the critical problem of estimating the missile-to-target position, velocity, and acceleration (required by the linear optimal guidance law) when only passive (angle only) seeker information is available onboard a highly maneuverable bank-to-turn missile concept. More specifically, the problem is how to model the target acceleration to achieve improved missile performance. Four target acceleration models coupled with an extended Kalman filter are presented and evaluated on a six-degree-of-freedom missile simulation to determine their estimation effectiveness and their influence on missile guidance.

Concepts and Algorithms for Terminal-Area Traffic Management

Abstract: The nation's air-traffic-control system is the subject of an extensive modernization program, including the planned introduction of advanced automation techniques. This paper gives an overview of a concept for automating terminal-area traffic management. Four-dimensional (4D) guidance techniques, which play an essential role in the automated system, are reviewed. One technique, intended for on-board computer implementation, is based on application of optimal control theory. The second technique is a simplified approach to 4D guidance intended for ground computer implementation. It generates advisory messages to help the controller maintain scheduled landing times of aircraft not equipped with on-board 4D guidance systems. An operational system for the second technique, recently evaluated in a simulation, is also described.

Optimal controllers for bank-to-turn CLOS guidance

Abstract: Linear quadratic optimal control theory is applied to the problem of bank-to-turn control in a CLOS guidance system. Both stationary and moving targets are treated, and the trade-off between controller complexity and autopilot realisability examined. The optimality of conventional control ideas is assessed. Finally, simulation results using a practical autopilot model confirm that these new controllers give improved guidance accuracy and reduced susceptibility to pitch-yaw crosscoupling.

On-board computer system for navigation, orientation and route optimization

Abstract: This paper presents a self-sufficient route guidance system for use in both trunk highway systems and inner-city street system.

Adaptive noise estimation 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 angle-only measurements are available. A standard filter for processing the measurements is the extended Kalman filter, the performance of which depends on the value selected for the measurement covariance. It is shown that the performance of this filter can be improved by estimating the,measurement covariance. Two methods for doing so are investigated: the limited-memory and the weighted limited-memory.

Missile guidance system

Abstract: A guidance system for a missile 20 comprises an optical sight 1 for aiming at a target, a manually-operable control 8 to generate control signals for guiding the missile in response to commands of an operator, an optical tracker 2 for tracking the missile in flight the tracker being arranged to generate further signals representative of the actual missile displacement from the tracker axis, and means such as a cable 12 for transmitting signals to the missile to effect guidance, the system further including a predictor 2c to provide signals representative of a predicted missile displacement from the tracker axis in response to the operator commands, a comparator 2b for comparing the predicted missile displacement signals with the actual missile displacement signals and providing a signal representative of any error therebetween, and switch means 2e, 2f whereby the missile can be controlled initially by the operator and subsequently additionally or alternatively by signals representative of the error between the predicted and actual missile displacements.

The Space Telescope alternate fine guidance sensor

Abstract: A study was conducted to develop a preliminary design for an alternate fine guidance sensor system for retrofit on the NASA Space Telescope. An electrostatically focused quadrant array detector was proposed for this application. Configuration studies verified the feasibility of using this sensor in the existing fine guidance system and within the given limits on mass, power, volume, processor capability, and thermal dissipation. Space Telescope control system simulations showed the proposed system to meet the required performance specifications and to be substantially more resistant to external disturbances than the baseline system.

Guidance method for controllable, non-powered projectiles

Abstract: A guidance method is proposed for controllable, non-powered projectiles which are guided on a trajectory to the target from a firing installation, by means of a guidance system based on the beam-rider method, which trajectory is optimised in such a manner that the speed of flight in the direction of the line of sight is a maximum at a specific point on the trajectory.

Stochastic models for estimating the effectiveness of a route guidance system

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. The models are formulated by considering the stochastic aspects of travel time and predicted values. The justification of these models are examined by using the travel time data gathered during the experiments performed in the pilot system constructed in Tokyo. The accuracy of the model is shown to be sufficient for estimating the efficiency of the system.

Direct ascent, deep space intercept model

Abstract: A stochastic computer model was developed to analyze a direct ascent, deep space intercept system. There are two error sources within the system: the deep space tracking system and the launch vehicle guidance system. The errors are modeled based on equipment performance data and analytical results. To compensate for the system errors, the requirements for a maneuverable intercept vehicle are developed. The requirements are described in terms of sensor acquisition distance and vehicle velocity change. Analyses of error sources and tradeoffs amongst maneuver factors are discussed.

The Space Telescope alternate fine guidance sensor

Abstract: A study was conducted to develop a preliminary design for an alternate fine guidance sensor system for retrofit on the NASA Space Telescope. An electrostatically focused quadrant array detector was proposed for this application. Configuration studies verified the feasibility of using this sensor in the existing fine guidance system and within the given limits on mass, power, volume, processor capability, and thermal dissipation. Space Telescope control system simulations showed the proposed system to meet the required performance specifications and to be substantially more resistant to external disturbances than the baseline system.