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Discretized Quaternion Constrained Attitude Pathfinding

JOURNAL OF guidance CONTROL AND DYNAMICS 2016年第3期39卷 713-718页

作者： Kjellberg, Henri C. Lightsey, E. Glenn Firefly Space Syst Austin TX 78727 USA Georgia Inst Technol Sch Aerosp Engn Atlanta GA 30332 USA

The new constrained attitude pathfinding algorithm has been generalized by using a quaternion formulation of the attitude pathfinding problem. The limitations of the previous implementation have been removed, allowing for any number of body-fixed attitude constraints and directions to be supported by a single algorithm. The new approach is also capable of satisfying other types of constraints, such as a constraint that is met as long as a single sensor in a group of sensors is able to view a specified external direction. By changing the way that the problem is formulated, an arbitrary number of sensitive directions distributed throughout the body frame can be paired with an arbitrary number of constraints in the external frame.

关键词： Quaternions Attitude guidance Earth Constellations IMU guidance algorithms Spacecraft Sensors

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Multiple Maneuvering Target Tracking Using a Single Unmanned Aerial Vehicle

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JOURNAL OF guidance CONTROL AND DYNAMICS 2019年第1期42卷 78-90页

作者： Zhang, Chiyu Hwang, Inseok Purdue Univ Sch Aeronaut & Astronaut W Lafayette IN 47907 USA

This paper solves the problem of tracking multiple maneuvering ground targets using an unmanned aerial vehicle (UAV). The targets are widespread so that they may not be covered by the UAV's detection range simultaneously. Such a strategy is applied in which, whenever it is unable to detect all the targets, the UAV temporarily covers only some of the targets and goes back to the lost targets later. A recursive Bayesian estimation algorithm is proposed to keep track of the lost targets;a guidance objective function is then formulated to minimize the tracking uncertainty. By integrating the proposed estimation and the guidance methods, an efficient closed-loop multitarget tracking algorithm is developed. The effectiveness of the proposed approach is demonstrated with illustrative numerical examples.

关键词： UAV Track Algorithm Closed Loop Kalman Filter Dead Reckoning guidance Laws Probability Density Functions White Noise guidance algorithms Monte Carlo Simulation

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Fixed-range optimal trajectories of supersonic aircraft by first-order expansions

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JOURNAL OF guidance CONTROL AND DYNAMICS 2001年第4期24卷 700-709页

作者： Windhorst, R Ardema, M Kinney, D Santa Clara Univ Dept Mech Engn Santa Clara CA 95053 USA NASA Ames Res Ctr Syst Anal Branch Moffett Field CA 94035 USA

A near-optimal guidance law that generates minimum-fuel, minimum-time, or direct operating cost fixed-range trajectories for supersonic transport aircraft is developed. The approach uses singular perturbation techniques to timescale decouple the equations of motion into three sets of dynamics, two of which are studied here: weight/range and energy The two-point boundary-value problems obtained by application of the maximum principle to the dynamic systems are solved using the method of matched asymptotic expansions. Both the weight/range and the energy dynamic solutions are carried out to first order. The two solutions are combined using the matching principle to form a uniformly valid approximation of the full fixed-range trajectory, Results show that the minimum-fuel trajectory has three segments: a minimum-fuel energy climb, a cruise climb, and a minimum-drag glide. The minimum-time trajectory also has three segments: a maximum dynamic pressure climb, a constant altitude cruise, and a maximum dynamic pressure descent. The minimum direct operating cost trajectory is an optimal combination of the preceding two trajectories. It is shown that for representative costs of fuel and flight time, the minimum direct operating cost trajectory is very similar to the minimum-fuel trajectory.

关键词： Supersonic Transport Aircraft Direct Operating Cost Singular Perturbation Boundary Value Problems Dynamic Pressure guidance Laws High Speed Civil Transport guidance algorithms Transversality Condition Aircraft Design

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Feasible Dubins Paths in Presence of Unknown, Unsteady Velocity Disturbances

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JOURNAL OF guidance CONTROL AND DYNAMICS 2015年第4期38卷 782-786页

作者： Wolek, Artur Woolsey, Craig Virginia Polytech Inst & State Univ Dept Aerosp & Ocean Engn Blacksburg VA 24061 USA AIAA Reston VA USA

The ability to compensate for disturbances when following a Dubins path can be improved by artificially increasing the turn radius used in path planning. Monte Carlo simulations suggest that these feasible Dubins paths minimize the mean, final crosstrack error when the path is followed using a standard guidance algorithm. Furthermore, the simulation results indicate that there is no appreciable benefit in planning paths with a turn radius, the planning radius marks the knee in the cross-track error curve for a steady disturbance. The cost of using the (suboptimal) feasible turn radius for path planning is an increase in the nominal path length and travel time. This tradeoff can be illustrated, for a given final course angle, using a trade-space plot that indicates the relative path lengths of the ideal and feasible Dubins paths. These trade-space plots can be helpful in selecting a desired end state because they highlight regions where a given final state will result in a large increase in the relative path length.

关键词： Path Planning Monte Carlo Simulation Feedback Control System UAV guidance Laws Closed Loop Power Spectral Density guidance algorithms Turbulence Models Optimal Control

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Reachable and Controllable Sets for Planetary Entry and Landing

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JOURNAL OF guidance CONTROL AND DYNAMICS 2010年第3期33卷 641-654页

作者： Benito, Joel Mease, Kenneth D. Univ Calif Irvine Irvine CA 92697 USA

Understanding the envelope of entry trajectories that a given planetary lander is capable of flying can be an important aid for mission analysis and design. Two characteristics of this envelope are considered: 1) the set of states reachable from a given entry state and 2) the set of entry states controllable to a given final state. Precise definitions of these sets are given and methods for computing them are presented. To illustrate their use, the sets are employed to characterize the performance of two vehicle configurations, a low lift-to-drag-ratio capsule and a mid lift-to-drag-ratio ellipsled, for Mars entry. Roles for the sets in evaluating entry trajectory planning algorithms, choosing a nominal entry state, and planning skip entries are described.

关键词： Lift to Drag Ratio Computing Flight Path Angle Dynamic Pressure Earth Aerodynamic Coefficients Heading Angle guidance algorithms Lift Coefficient Trajectory Optimization

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Selective Velocity Obstacle Method for Deconflicting Maneuvers Applied to Unmanned Aerial Vehicles

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JOURNAL OF guidance CONTROL AND DYNAMICS 2015年第6期38卷 1140-1145页

作者： Jenie, Yazdi I. van Kampen, Erik-Jan de Visser, Coen C. Ellerbroek, Joost Hoekstra, Jacco M. Delft Univ Technol Control & Simulat Sect Fac Aerosp Engn NL-2629 HS Delft Netherlands

A study reviews the novel selective velocity obstacle method that supports unmanned aerial vehicle autonomous collision avoidance. The selective velocity obstacle (SVO) is shown to be able to generate deconflict maneuvers separately to resolve heterogeneous situations, while obeying the right-of-way rules, using a distance based prescribed turning rate. Problems in the original velocity obstacle method are resolved in the SVO method and validated trough a Monte Carlo simulations procedure. The procedure also reveals that, in a random situation setup, multiple encounters are very unlikely to happen;hence, the SVO method only needs to resolve conflicts in one-by-one manner. Several challenges in the method are noted, such as the late onset in restoring to the mission mode. The results show that the SVO method is a suitable method to reduce the risk of collision, and hence increase the safety of unmanned aerial vehicle operations in the airspace system.

关键词： UAV Airborne Collision Avoidance System Controlled Airspace Automatic Dependent Surveillance Broadcast Monte Carlo Simulation Aerospace Engineering Air Traffic Control Visual Flight Rules Unmanned Aerial Systems guidance algorithms

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Receding-Horizon Trajectory Planning Algorithm for Passively Safe On-Orbit Inspection Missions

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JOURNAL OF guidance CONTROL AND DYNAMICS 2019年第5期42卷 1023-1032页

作者： Capolupo, Francesco Labourdette, Pierre Airbus Def & Space Flight Dynam & AOCS GNC Adv Studies Dept F-31400 Toulouse France Natl Ctr Space Studies F-31400 Toulouse France

This paper presents a sampling-based receding-horizon inspection algorithm that allows observation of a tumbling target vehicle while guaranteeing an arbitrary low risk of collision between the chaser performing the inspection and the target. The proposed algorithm relies on a simple heuristic search of the best inspection trajectory, and it can be suited to both onboard implementation as an autonomous guidance module and offline trajectory design. The main strength of the algorithm resides in its ability to quickly solve black-box optimal control problems, exploiting an input sampling approach that is commonly used in robotic motion planning. A new and computationally simple method to verify the safety of the two vehicles is also presented and implemented into the algorithm. The proposed method allows taking into account relative navigation and maneuver execution errors, as well as the effects of unmodeled perturbations. The results obtained with the algorithm are compared to the ones obtained with a classic inspection strategy making use of inclined football orbits. It is shown that the proposed guidance algorithm consistently ensures the completion of the inspection mission, and it takes advantage of the characteristics of the natural dynamics of the relative motion to outperform the classic approach.

关键词： Motion Planning guidance algorithms Black Box Optimal Control Propellant Eclipses Spacecraft Trajectories Cumulative Distribution Function Solar Electric Propulsion Attitude Control System

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Aerial Rendezvous of Small Unmanned Aircraft Using a Passive Towed Cable System

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JOURNAL OF guidance CONTROL AND DYNAMICS 2014年第4期37卷 1131-1142页

作者： Nichols, Joseph W. Sun, Liang Beard, Randal W. McLain, Timothy Brigham Young Univ Provo UT 84602 USA

A method for aerial rendezvous of small unmanned aircraft systems is proposed. The system includes placing a passively towed drogue into an orbit that is suitable for a small unmanned aircraft systems to follow, and a seeker guidance method for use with a monocular camera mounted on the centerline of the unmanned aircraft systems. The principle contributions of the work include a method for controlling the drogue path in moderate winds by manipulating the mothership orbit and airspeed, and a vision-based nonlinear pursuit tracking method that uses pitch rate and roll commands to guide the unmanned aircraft systems to an aerial rendezvous with the drogue. Simulation and flight-test results are presented to demonstrate the suitability of these methods.

关键词： Airspeed Small Unmanned Aircraft System Experimental Flight Test Autopilot Ground Station Aerial Refueling Aerodynamic Drag Control Algorithm guidance algorithms Longitudinal Control

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APPLICATION OF TOTAL ENERGY CONTROL FOR HIGH-PERFORMANCE AIRCRAFT VERTICAL TRANSITIONS

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JOURNAL OF guidance CONTROL AND DYNAMICS 1991年第2期14卷 447-452页

作者： WARREN, A Boeing Co. Seattle WA

Energy management guidance algorithms for automated, fast transitions between cruise states are presented. These algorithms use total energy control principles to regulate throttle and flight control inputs. Two principal algorithms are used to perform cruise state transitions. 1) Energy hold/altitude hold: This algorithm consists of two guidance laws that regulate thrust and vertical lift to acquire and maintain a desired height/energy cruise point. 2) Energy capture: This algorithm regulates flight-path angle at fixed throttle to coordinate height/speed transitions to a desired cruise point. It is primarily used for large energy transitions at maximum or minimum throttle settings, and requires switching to energy hold/altitude hold as the cruise state is approached. Algorithm performance is illustrated using five-degree-of-freedom simulations of a modern, high-performance fighter aircraft.

关键词： Total Energy High Performance Aircraft Flight Path Angle guidance Laws Energy Management guidance algorithms Aircraft Flight Control Fighter Aircraft Algorithm Performance Angle of Attack

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Direct trajectory optimization by a Chebyshev pseudospectral method

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JOURNAL OF guidance CONTROL AND DYNAMICS 2002年第1期25卷 160-166页

作者： Fahroo, F Ross, IM USN Postgrad Sch Dept Math Monterey CA 93943 USA USN Postgrad Sch Dept Aeronaut & Astronaut Monterey CA 93943 USA

We present a Chebyshev pseudospectral method for directly solving a generic Bolza optimal control problem with state and control constraints. This method employs Nth-degree Lagrange polynomial approximations for the state and control variables with the values of these variables at the Chebyshev-Gauss-Lobatto (CGL) points as the expansion coefficients. This process yields a nonlinear programming problem (NLP) with the state and control values at the CGL points as unknown NLP parameters. Numerical examples demonstrate that this method yields more accurate results than those obtained from the traditional collocation methods.

关键词： Chebyshev Pseudospectral Method Trajectory Optimization Nonlinear Programming Numerical Integration Moon Landing Propellant guidance algorithms Soft Landing MATLAB Planets

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