Variable-Time-Domain Neighboring Optimal Guidance, Part 2: Application to Lunar Descent and Soft Landing

AbstractAccurate orbit injection represents a crucial issue in several mission scenarios, e.g., for spacecraft orbiting the Earth or for payload release from the upper stage of an ascent vehicle. This work considers a new guidance and control architecture based on the combined use of (i) the variable-time-domain neighboring optimal guidance technique (VTD-NOG), and (ii) the constrained proportional-derivative (CPD) algorithm for attitude control. More specifically, VTD-NOG & CPD is applied to two distinct injection maneuvers: (a) Hohmann-like finite-thrust transfer from a low Earth orbit to a geostationary orbit, and (b) orbit injection of the upper stage of a launch vehicle. Nonnominal flight conditions are modeled by assuming errors on the initial position, velocity, attitude, and attitude rate, as well as actuation deviations. Extensive Monte Carlo campaigns prove effectiveness and accuracy of the guidance and control methodology at hand, in the presence of realistic deviations from nominal flight conditions.

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A Computationally Inexpensive Optimal Guidance via Radial-Basis-Function Neural Network for Autonomous Soft Landing on Asteroids

PLoS ONE ◽

10.1371/journal.pone.0137792 ◽

2015 ◽

Vol 10 (9) ◽

pp. e0137792 ◽

Cited By ~ 1

Author(s):

Peng Zhang ◽

Keping Liu ◽

Bo Zhao ◽

Yuanchun Li

Keyword(s):

Neural Network ◽

Radial Basis Function ◽

Basis Function ◽

Soft Landing ◽

Optimal Guidance ◽

Radial Basis

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Waypoint Constrained Multi-Phase Optimal Guidance of Spacecraft for Soft Lunar Landing

Unmanned Systems ◽

10.1142/s230138501950002x ◽

2019 ◽

Vol 07 (02) ◽

pp. 83-104 ◽

Cited By ~ 3

Author(s):

Kapil Sachan ◽

Radhakant Padhi

Keyword(s):

Selection Procedure ◽

Landing Site ◽

Terminal Point ◽

Computationally Efficient ◽

Soft Landing ◽

Hard Constraints ◽

Optimal Guidance ◽

Safety Constraints ◽

Multi Phase ◽

Time Selection

A waypoint constrained multi-phase nonlinear optimal guidance scheme is presented in this paper for the soft landing of a spacecraft on the Lunar surface by using the recently developed computationally efficient Generalized Model Predictive Static Programming (G-MPSP). The proposed guidance ensures that the spacecraft passes through two waypoints, which is a strong requirement to facilitate proper landing site detection by the on-board camera for mission safety. Constraints that are required at the waypoints as well as at the terminal point include position, velocity, and attitude of the spacecraft. In addition to successfully meeting these hard constraints, the G-MPSP guidance also minimizes the fuel consumption, which is a very good advantage. An optimal final time selection procedure is also presented in this paper to facilitate minimization of fuel requirement to the best extent possible. Extensive simulation studies have been carried out with various perturbations to illustrate the effectiveness of the algorithm. Finally, processor-in-loop simulation has been carried out, which demonstrates the feasibility of on-board implementation of the proposed guidance.

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