Pith. sign in

REVIEW 3 major objections 5 minor 65 references

Initial Guess Generation for Low-Thrust Trajectory Design with Robustness to Missed-Thrust-Events

T0 review · 3 major / 5 minor · reviewed 2026-08-10 · deepseek-v4-flash

Pith's one-line read Warm-starting robust low-thrust searches with non-robust solutions improves feasibility, speed, and fuel across missed-thrust depths.

desk verdict Warm-starting robust MTE design from non-robust solutions looks genuinely better on direct metrics, but the paper's cumulative time accounting is off by a factor of 1/F and the 'significant' claim has no significance test behind it. read the letter →

arxiv 2501.06694 v1 pith:UN7WRZCS submitted 2025-01-12 math.OC

classification math.OC MSC 49K1590C3090C2670M20
keywords low-thrusttrajectorydesignmissed-thrusteventsrobustoptimalcontrolinitialguessgenerationconditionalwarmstartglobalsearchcislunartransfernonlinearprogramming
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

Low-thrust spacecraft missions are vulnerable to missed-thrust events, but designing trajectories that survive them is computationally difficult because the robust problem is a high-dimensional nonlinear program with few feasible regions. This paper proposes generating initial guesses for a robust problem $P_k$ by projecting previously computed solutions to a simpler problem $P_{k'}$ — in particular the non-robust problem $P_0$ — into the robust decision space, instead of sampling uniformly from the global space. In a Lunar Gateway Power and Propulsion Element transfer to a near-rectilinear halo orbit, the conditional strategy $S(k|0)$ attains higher feasibility ratios, lower average solving times, and lower propellant costs than non-conditional uniform sampling, with the advantage persisting through robustness depths $k=1,2,3$ even after accounting for seed-generation cost in cumulative metrics. The paper concludes that feasible-region access, not partial robustness of the seed, governs initial-guess quality.

What carries the argument

The central object is the conditional initial-guess generator $S(k|k') = \pi \circ M^{k}_{k'}$, where $M^{k}_{k'}$ maps an optimal solution of a lower-robustness problem $P_{k'}$ into the decision space of $P_k$ and $\pi$ is the solver's projection onto a local optimum. The mapping is not unique: realization-to-realization assignments are counted by $C^{k}_{k'} = k'^k + 1$, and the paper uses the simplest reference-to-realization mapping after excluding control segments before the missed-thrust event, with zero initialized realization coast time. This projection carries the argument by placing initial guesses in basins of attraction that survive increasing robustness depth, while adaptive segmentation of realization trajectories keeps control authority comparable and keeps the Jacobian sparse. The alternative, $S(k)$, samples uniform global distributions and is the exploration baseline whose decay in feasibility with $k$ is the contrast that makes the conditional advantage visible.

What would settle it

Re-run the $P_1$, $P_2$, and $P_3$ comparisons with missed-thrust initiation points drawn from all 50 reference segments and durations sampled from the full historical Weibull distribution, including outages beyond 1.5 days, keeping cumulative seed-generation cost in the metrics; if $S(k|0)$ no longer dominates $S(k)$ in feasibility or cumulative solving time at $k \ge 2$, the paper's central claim fails.

Watch

Extended reading notes

Core claim

The central claim is that the performance of global search for missed-thrust-robust low-thrust trajectories is controlled by how initial guesses are generated, and that conditioning those guesses on solutions of a less robust problem is systematically better than unconditional sampling. Concretely, the paper defines $P_k$ as the robust optimal control problem with $k$ realization trajectories, one per missed-thrust scenario, for $k=0,\dots,3$, and compares $S(k)$, which samples a fixed global distribution, with $S(k|k')$, which maps optimal solutions of $P_{k'}$ into the higher-dimensional decision space of $P_k$. Across all tested outage durations, $S(k|0)$ yields the highest feasibility ratios, the lowest mean solving times, and the best (lowest) $\Delta v$ distributions; $S(3|0)$ even beats seeds from partially robust problems $S(3|1)$ and $S(3|2)$, because seeds from more constrained problems often map into infeasible regions. The authors state that $S(k|0)$ appears to be the optimal initial guess generation strategy and interpret the result as evidence that feasible-region accessibility dominates partial-robustness information.

Load-bearing premise

The load-bearing premise is that the discretized missed-thrust model — at most one outage per mission, starting at one of three fixed points on the transfer, and lasting 0.5, 1.0, or 1.5 days — faithfully represents the real missed-thrust risk; the paper itself notes these durations cover roughly 40% of observed outage durations, so outages elsewhere or longer than 1.5 days lie outside the tested design space.

Editorial extensions

If this is right

  • For robust missed-thrust design at depths $k=1,2,3$, initializing from non-robust solutions yields higher feasibility ratios and lower mean $\Delta v$ than sampling from a fixed global distribution.
  • The advantage persists in cumulative metrics that include the cost of producing the seed solutions: conditional search has comparable or better cumulative feasibility at depth $k=3$ and better cumulative solving time at higher robustness depths.
  • Seeding from non-robust solutions outperforms seeding from partially robust solutions at depths 2 and 3, so robustness of the seed is secondary to feasible-region accessibility.
  • Conditional search reduces solution diversity, so a mission design phase wanting a broad family of options may need to seed from a diverse set of non-robust solutions or mix strategies.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • If the feasible-region-access explanation is general, then any method that broadens the basin coverage of low-robustness solutions, such as denser basin hopping around multiple non-robust optima, should amplify the conditional gain at high $k$.
  • The same conditional seeding idea may transfer to other high-dimensional robust trajectory problems with multiple realization scenarios, whenever the feasible set shrinks monotonically with robustness depth.
  • Because the paper tests only three missed-thrust locations and durations up to 1.5 days, an immediate testable extension is to condition on non-robust seeds under missed-thrust initiation at all 50 reference segments and durations drawn from the full historical Weibull distribution.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 5 minor

Summary. The paper considers a finite-realization robust optimal control formulation for low-thrust transfers subject to missed-thrust events (MTEs), with at most one MTE and a small set of initiation times and durations. It compares two global-search initialization strategies: a non-conditional strategy S(k), which uses uniform sampling with monotonic basin hopping, and a conditional strategy S(k|k'), in which solutions to a less robust problem P_{k'} are mapped into initial guesses for P_k. The comparison uses feasibility ratio, average solving time, and Delta-v, together with cumulative versions of the feasibility and time metrics that account for seed-generation cost. In a Lunar Gateway Power and Propulsion Element case study, the authors report that S(k|0) improves feasibility and solution quality over S(k) and discuss how these advantages evolve with depth of robustness k.

Significance. The question is practical and timely: if the empirical advantage of conditional seeding is robust, this is a useful, low-cost heuristic for preliminary robust low-thrust trajectory design. The paper's strengths include a realistic high-dimensional cislunar case study, a clear problem transcription with analytic derivatives drawn from prior work, and a genuine attempt to define cumulative metrics so that seed-generation overhead is not ignored. The main limitations are inferential: the headline claim of statistical significance is not backed by any test or confidence interval, and the cumulative time accounting appears to undercount seed cost. These issues affect the central claim but are addressable within the manuscript's scope.

major comments (3)
  1. [§VI, Table 8 and Figs. 10–15] The abstract and §I state that the conditional approach 'significantly improves' convergence rate and solution quality, but no statistical test, confidence interval, or bootstrap analysis appears anywhere in §VI. The sample sizes at higher depths are very small: Table 8 reports only 3–8 feasible S(3) solutions with feasibility ratios of 0.08–0.22%, so the point-estimate comparisons in Figs. 11–13 and 14–15 may lie within sampling noise. Please provide two-sample bootstrap intervals for the Δv distributions and binomial confidence intervals for the feasibility ratios, or restrict the claims to the observed samples.
  2. [§VI, Fig. 17] The cumulative solving time for S(k|0) is defined as the sum of the S(0) time per solution and the S(k|0) time per solution. This undercounts the seed-generation cost: if each conditional solve consumes one feasible P0 seed and only a fraction F_{k|0} of conditional solves succeed, the expected number of P0 seeds per final conditional solution is 1/F_{k|0}, so the seed contribution is T_0/F_{k|0}, not T_0. Since Fig. 14 shows F_{k|0} can be near or below 0.1, this is at least a tenfold correction to the seed term. The §VII conclusion that conditional methods achieve better cumulative average solving times at higher robustness depths is not supported by the metric as defined; recompute the cumulative time with the expected seed usage or report total wall-clock time per final feasible solution for each complete pipeline.
  3. [§II.B and Tables 6–7] The validated scenario set is narrow: Assumption A1 excludes multiple MTEs, and the text states that the tested durations up to 1.5 days cover roughly 40% of observed outage durations. Because the relative difficulty of P_k versus P_0 depends on which MTE scenarios are included, the ranking of conditional versus non-conditional search has been demonstrated only for this particular subset of the risk distribution. Please add a sensitivity study (for example, longer outages, additional initiation locations, or a second MTE) or explicitly delimit the paper's claim to the tested scenario distribution.
minor comments (5)
  1. [§III.A, Eq. (9)] The conditional strategy is written as S(k|k') ≡ π∘M_k^{k'}, but the definition two paragraphs earlier includes the seed-generation map π∘X_{k'}; either define M_k^{k'} to include that composition or fix the equation for consistency.
  2. [§II.B and Table 6] The text says the analysis is restricted to a maximum of three MTE initiation points, but Table 6 lists ten segment indices for P1 and Table 7 lists pairs and triples of indices; reconcile the stated assumption with the actually tested sets.
  3. [Nomenclature] The symbol N is defined twice in the nomenclature, once as 'number of segments' and once as 'number of decision variables'; please use distinct symbols.
  4. [§VI, Table 8] Please state explicitly whether 'Time/Solution' is wall-clock time per feasible solution or per initial guess; this distinction is necessary for interpreting the cumulative time metric in Fig. 17.
  5. [Throughout] Minor language errors remain, for example 'has been been explored' in §I and 'with with number' in §II.C; a careful copyedit is needed.

Circularity Check

0 steps flagged · score 2.0 of 10

No significant circularity: the conditional-vs-nonconditional comparison is an independent empirical benchmark; self-citations to prior work are foundational but not load-bearing.

full rationale

The paper's central claim is an empirical comparison of two initial-guess generation strategies on a fixed robust trajectory optimization problem, and nothing in the derivation forces the outcome. The robust problem formulation and analytic derivatives are taken from the authors' earlier work [27,45], and the solver DyLAN is also the authors' own [42]; however, these ingredients are shared identically by both strategies being compared, so they cannot by construction determine which strategy converges more often, faster, or to better solutions. Indeed, the paper reports results that could have gone the other way (e.g., S(3|0) outperforming S(3|1) despite the intuition that partially robust seeds should help), and Figure 16 shows the non-conditional strategy retaining higher cumulative feasibility at P1 and P2. The cumulative-time metric in Figure 17 is open to a legitimate correctness objection: the seed-generation time is added rather than divided by the relevant feasibility ratios, which may undercount the true cost of the conditional approach at higher depths; but that is an accounting/statistical issue, not a circular reduction of the conclusion to its inputs. The paper does not define the robust problem in terms of the search outcome, nor does it fit a parameter and then relabel it as a prediction. The self-citations are thus minor and non-load-bearing for the central empirical claim; they do not make the derivation circular.

Assumptions & free parameters 5 free parameters · 8 assumptions · 0 invented entities

The comparison depends on the restricted MTE uncertainty model and on hand-chosen scenario sets. No numerical constants are fitted to the headline result, but the set of tested problems is narrow enough that the generality of the conclusion is open.

free parameters (5)
  • MTE duration scenarios = 0.5, 1.0, 1.5 days
    Chosen by hand to cover part of the historical outage duration distribution; the central comparison of S(k) vs S(k|k') is only tested at these durations.
  • MTE initiation segment indices = Various sets in Tables 6-7 (e.g., {4,8,...,48} for P1)
    Selected to cover beginning, middle, and end of transfer; results may depend on this selection.
  • Maximum depth of robustness K = 3 realizations
    Limited for computational tractability; the paper's main positive results at P3 rely on very few successful solutions.
  • SNOPT runtime scaling factor = 1+k
    Chosen to give each robustness level proportional convergence time; directly affects time-to-solve metrics.
  • Number of reference segments N† = 50
    Chosen to balance control authority and computational cost; affects the structure of the NLP and the mapping strategy.
assumptions (8)
  • domain assumption At most one MTE occurs per realization (Assumption A1).
    Justified by a Weibull fit from Imken et al. [1], covering about 90% of MTE scenarios; restricts the robust design problem to a single outage per realization.
  • domain assumption At most three MTE initiation points are considered, at the start, middle, and end of the transfer (Assumption A2).
    Reduces the infinite-dimensional uncertainty to three discrete initiation locations; stated in §II.B.
  • domain assumption Only a finite set of MTE durations is allowed, up to 1.5 days (Assumption A3).
    Three durations represent roughly 40% of observed outage durations; stated in §II.B.
  • domain assumption Each robust problem uses a probability distribution supported only on its chosen interval of MTE scenarios (Assumption A4).
    The tested problems are a sparse sample of the full uncertainty space, not an approximation of the continuous distribution.
  • domain assumption Point-mass N-body ephemeris model with Earth, Moon, Sun, and Jupiter.
    Higher-order gravity terms and solar radiation pressure are neglected; stated in §IV.
  • domain assumption Finite-burn constant-thrust transcription with forward-backward multiple shooting.
    The trajectory is discretized into 50 segments with constant thrust per segment, reducing the optimal control problem to an NLP in §II.C.
  • domain assumption Monotonic basin hopping with uniform sampling is a valid baseline global search implementation.
    The non-conditional strategy S(k) is implemented with MBH and uniform sampling; all comparisons are relative to this particular baseline.
  • domain assumption SNOPT converges to meaningful local optima from the provided initial guesses.
    The solver defines the map pi from initial guesses to solutions; the comparison assumes these local solutions represent the relevant landscape.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Initial Guess Generation for Low-Thrust Trajectory Design with Robustness to Missed-Thrust-Events." pith.science (2026). https://pith.science/paper/UN7WRZCS

@misc{pith2026250106694,
  author       = {Pith},
  title        = {Pith review of: Initial Guess Generation for Low-Thrust Trajectory Design with Robustness to Missed-Thrust-Events},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/UN7WRZCS}},
  note         = {Machine review of arXiv:2501.06694}
}
read the original abstract

The growing interest in cislunar space exploration in recent years has driven an increasing demand for efficient low-thrust missions to key cislunar orbits. These missions, typically possessing long thrust arcs, are particularly susceptible to operational uncertainties such as missed thrust events. Addressing these challenges requires efficient robust trajectory design frameworks during the preliminary mission design phase, where it is necessary to explore the solution space at a rapid cadence under evolving operational constraints. However, existing methods for missed thrust design rely on solving high-dimensional nonlinear programs, where generating effective initial guesses becomes challenging. To enhance computational efficiency, quality, and depth of robustness of solutions from global search, we compare two initial guess strategies: a baseline non-conditional global search, which samples from a static distribution with global support, and a conditional global search, which generates initial guesses conditioned on solutions to problems with less depth of robustness. The conditional search provides a sequential procedure for solving increasingly robust problems. We validate the improvements in the conditional approach using a low-thrust case study for the Lunar Gateway Power and Propulsion Element, where our results demonstrate that it significantly improves convergence rate and solution quality, highlighting its potential in preliminary robust trajectory design.

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

65 extracted references · 46 canonical work pages

  1. [1]

    Modeling spacecraft safe mode events,

    Imken, T., Randolph, T., DiNicola, M., and Nicholas, A., “Modeling spacecraft safe mode events,”2018 IEEE Aerospace Conference, Big Sky, MT, 2018. https://doi.org/10.1109/AERO.2018.8396383

  2. [2]

    Power and Propulsion Element (PPE) Spacecraft Reference Trajectory Document,

    McGuire, M. L., McCarty, S. L., and Burke, L. M., “Power and Propulsion Element (PPE) Spacecraft Reference Trajectory Document,” Tech. Rep. NASA/TM—2020-220481, March 2020

  3. [3]

    Overview of the Lunar Transfer Trajectory of the Co-manifested First Elements of NASA’s Gateway,

    McGuire, M., McCarty, S., Karn, S., Ponnapalli, K., Hack, K., Grebow, D., Pavlak, T., and Davis, D., “Overview of the Lunar Transfer Trajectory of the Co-manifested First Elements of NASA’s Gateway,”AAS/AIAA Astrodynamics Specialist Conference, Big Sky, MT (Virtual), 2021

  4. [4]

    Anewmethodforthenonlineartransformationofmeansandcovariancesinfilters and estimators,

    Julier,S.,Uhlmann,J.,andDurrant-Whyte,H.,“Anewmethodforthenonlineartransformationofmeansandcovariancesinfilters and estimators,”IEEE Transactions on Automatic Control, Vol. 45, No. 3, 2000, pp. 477–482. https://doi.org/10.1109/9.847726

  5. [5]

    Unscented guidance,

    Ross, I. M., Proulx, R. J., and Karpenko, M., “Unscented guidance,” 2015, pp. 5605–5610. https://doi.org/10.1109/ACC.2015. 7172217

  6. [6]

    Stochastic Differential Dynamic Programming with Unscented Transform for Low-Thrust Trajectory Design,

    Ozaki, N., Campagnola, S., Funase, R., and Yam, C. H., “Stochastic Differential Dynamic Programming with Unscented Transform for Low-Thrust Trajectory Design,”Journal of Guidance, Control, and Dynamics, Vol. 41, No. 2, 2018, pp. 377–387. https://doi.org/10.2514/1.G002367. 34

  7. [7]

    TubeStochasticOptimalControlforNonlinearConstrainedTrajectoryOptimization Problems,

    Ozaki,N.,Campagnola,S.,andFunase,R.,“TubeStochasticOptimalControlforNonlinearConstrainedTrajectoryOptimization Problems,”JournalofGuidance,Control,andDynamics ,Vol.43,No.4,2020,pp.645–655. https://doi.org/10.2514/1.G004363

  8. [8]

    Robust Spacecraft Guidance Around Small Bodies Under Uncertainty: Stochastic Optimal Control Approach,

    Oguri, K., and McMahon, J. W., “Robust Spacecraft Guidance Around Small Bodies Under Uncertainty: Stochastic Optimal Control Approach,” Journal of Guidance, Control, and Dynamics, Vol. 44, No. 7, 2021, pp. 1295–1313. https://doi.org/10.2514/1.G005426, URL https://doi.org/10.2514/1.G005426

Show all 65 references
  1. [9]

    Stochastic Primer Vector for Robust Low-Thrust Trajectory Design Under Uncertainty,

    Oguri, K., and McMahon, J. W., “Stochastic Primer Vector for Robust Low-Thrust Trajectory Design Under Uncertainty,” Journal of Guidance, Control, and Dynamics, Vol. 45, No. 1, 2022, pp. 84–102. https://doi.org/10.2514/1.G005970, URL https://doi.org/10.2514/1.G005970

  2. [10]

    Optimal Covariance Control for Stochastic Systems Under Chance Constraints,

    Okamoto, K., Goldshtein, M., and Tsiotras, P., “Optimal Covariance Control for Stochastic Systems Under Chance Constraints,” IEEE Control Systems Letters, Vol. 2, No. 2, 2018, pp. 266–271. https://doi.org/10.1109/LCSYS.2018.2826038

  3. [11]

    Nonlinear Covariance Control via Differential Dynamic Programming,

    Yi, Z., Cao, Z., Theodorou, E., and Chen, Y., “Nonlinear Covariance Control via Differential Dynamic Programming,” 2020, pp. 3571–3576. https://doi.org/10.23919/ACC45564.2020.9147531

  4. [12]

    Robust Space Trajectory Design Using Belief Optimal Control,

    Greco, C., Campagnola, S., and Vasile, M., “Robust Space Trajectory Design Using Belief Optimal Control,”Journal of Guidance, Control, and Dynamics, Vol. 45, No. 6, 2022, pp. 1060–1077. https://doi.org/10.2514/1.G005704

  5. [13]

    Coupling of System Resource Margins through the Use of Electric Propulsion: Implications in Preparing for the Dawn Mission to Ceres and Vesta,

    Rayman, M. D., Fraschetti, T. C., Raymond, C. A., and Russell, C. T., “Coupling of System Resource Margins through the Use of Electric Propulsion: Implications in Preparing for the Dawn Mission to Ceres and Vesta,”Acta Astronautica, Vol. 60, No. 10, 2007, pp. 930–938. https://...

  6. [14]

    Analysis of System Margins on Deep Space Missions Using Solar Electric Propulsion,

    Oh, D., Landau, D., Randolph, T., Timmerman, P., Chase, J., Sims, J., and Kowalkowski, T., “Analysis of System Margins on Deep Space Missions Using Solar Electric Propulsion,”44th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit,

  7. [15]

    Missed Thrust Requirements for Psyche Mission,

    Madni, A. A., Hart, W., Imken, T., Oh, D. Y., and Snyder, S., “Missed Thrust Requirements for Psyche Mission,”AIAA Propulsion and Energy 2020 Forum, 2020. https://doi.org/10.2514/6.2020-3608

  8. [16]

    Automated Missed-Thrust Propellant Margin Analysis for Low-Thrust Trajectories,

    Laipert, F. E., and Longuski, J. M., “Automated Missed-Thrust Propellant Margin Analysis for Low-Thrust Trajectories,” Journal of Spacecraft and Rockets, Vol. 52, No. 4, 2015, pp. 1135–1143. https://doi.org/10.2514/1.A33264

  9. [17]

    A Monte Carlo Approach to Measuring Trajectory Performance Subject to Missed Thrust,

    Laipert, F. E., and Imken, T., “A Monte Carlo Approach to Measuring Trajectory Performance Subject to Missed Thrust,”28th AIAA/AAS Space Flight Mechanics Meeting, Kissimmee, FL, 2018. https://doi.org/10.2514/6.2018-0966

  10. [18]

    Missed Thrust Analysis and Design For Low Thrust Cislunar Transfers,

    McCarty, S. L., and Grebow, D. J., “Missed Thrust Analysis and Design For Low Thrust Cislunar Transfers,”AAS/AIAA Astrodynamics Specialist Conference, South Lake Tahoe, CA, 2020

  11. [19]

    Multi-Objective Low-Thrust Trajectory Optimization with Robustness to Missed Thrust Events,

    Venigalla, C., Englander, J. A., and Scheeres, D. J., “Multi-Objective Low-Thrust Trajectory Optimization with Robustness to Missed Thrust Events,”Journal of Guidance, Control, and Dynamics, Vol. 45, No. 7, 2020, pp. 1255–1268. https: //doi.org/10.2514/1.G006056. 35

  12. [20]

    Designingrobustlow-thrustinterplanetarytrajectoriessubjecttoonetemporaryenginefailure,

    Olympio,J.T.,“Designingrobustlow-thrustinterplanetarytrajectoriessubjecttoonetemporaryenginefailure,” 20thAIAA/AAS Space Flight Mechanics Meeting, American Astronautical Society, Univelt Inc, Escondido, CA, 2010, pp. 10–171

  13. [21]

    Designing trajectories resilient to missed thrust events using expected thrust fraction,

    Rubinsztejn, A., Sandel, C. G., Sood, R., and Laipert, F. E., “Designing trajectories resilient to missed thrust events using expected thrust fraction,”Aerospace Science and Technology, Vol. 115, 2021, p. 106780. https://doi.org/https: //doi.org/10.1016/j.ast.2021.106780

  14. [22]

    Neural Network Optimal Control in Astrodynamics: Application to the Missed Thrust Problem,

    Rubinsztejn, A., Sood, R., and Laipert, F. E., “Neural Network Optimal Control in Astrodynamics: Application to the Missed Thrust Problem,”Acta Astronautica, Vol. 176, 2020, pp. 192–203. https://doi.org/10.1016/j.actaastro.2020.05.027

  15. [23]

    Real-Time Guidance for Low-Thrust Transfers Using Deep Neural Networks,

    Izzo, D., and Öztürk, E., “Real-Time Guidance for Low-Thrust Transfers Using Deep Neural Networks,”Journal of Guidance, Control, and Dynamics, Vol. 44, No. 2, 2021, pp. 315–327. https://doi.org/10.2514/1.G005254

  16. [24]

    Low-ThrustOptimalControlviaReinforcementLearning,

    Miller,D.,andLinares,R.,“Low-ThrustOptimalControlviaReinforcementLearning,” 29thAIAA/AASSpaceFlightMechanics Meeting, American Astronautical Society, Univelt Inc, Ka’anapali, Hawaii, 2019, pp. 1–18

  17. [25]

    Reinforcement Learning for Robust Trajectory Design of Interplanetary Missions,

    Zavoli, A., and Federici, L., “Reinforcement Learning for Robust Trajectory Design of Interplanetary Missions,”Journal of Guidance, Control, and Dynamics, Vol. 44, No. 8, 2021, pp. 1440–1453. https://doi.org/10.2514/1.G005794

  18. [26]

    Sensitivity Reduction and Lifetime Extension of Power-Limited Low-Thrust Trajectories,

    Alizadeh, I., and Villac, B. F., “Sensitivity Reduction and Lifetime Extension of Power-Limited Low-Thrust Trajectories,” Journal of Guidance, Control, and Dynamics, Vol. 36, No. 1, 2013, pp. 218–228. https://doi.org/10.2514/1.56480

  19. [27]

    Statistical Analysis of the Role of Invariant Manifolds on Robust Trajectories,

    Sinha, A., and Beeson, R., “Statistical Analysis of the Role of Invariant Manifolds on Robust Trajectories,” , 2024. URL https://arxiv.org/abs/2409.19905

  20. [28]

    https://doi.org/10

    Locatelli, M., and Schoen, F.,Global Optimization, Society for Industrial and Applied Mathematics, 2013. https://doi.org/10. 1137/1.9781611972672

  21. [29]

    Optimal Interplanetary Spacecraft Trajectories via a Pareto Genetic Algorithm,

    Hartmann, J. W., Coverstone-Carroll, V. L., and Williams, S. N., “Optimal Interplanetary Spacecraft Trajectories via a Pareto Genetic Algorithm,”The Journal of the Astronautical Sciences, Vol. 46, No. 3, 1998, pp. 267–282. https: //doi.org/10.1007/BF03546237, URL https://doi.o...

  22. [30]

    Primer Vector Theory Applied to Global Low-Thrust Trade Studies,

    Russell, R. P., “Primer Vector Theory Applied to Global Low-Thrust Trade Studies,”Journal of Guidance, Control, and Dynamics, Vol. 30, No. 2, 2007, pp. 460–472. https://doi.org/10.2514/1.22984

  23. [31]

    Global search for low-thrust transfers to the Moon in the planar circular restricted three-body problem,

    Oshima, K., Campagnola, S., and Yanao, T., “Global search for low-thrust transfers to the Moon in the planar circular restricted three-body problem,”Celestial Mechanics and Dynamical Astronomy, Vol. 128, No. 2, 2017, pp. 303–322. https://doi.org/10.1007/s10569-016-9748-2

  24. [32]

    Advanced Global Optimisation Tools for Mission Analysis and Design,

    Lizia, P. D., and Radice, G., “Advanced Global Optimisation Tools for Mission Analysis and Design,” Final Report AO4532/18139/04/NL/MV, European Space Agency, 11 2004. URL https://www.esa.int/gsp/ACT/doc/ARI/ARI%20Study% 20Report/ACT-RPT-MAD-ARI-03-4101b-GlobalOptimisation-Gla...

  25. [33]

    Preliminary Design of Multiple Gravity-Assist Trajectories,

    Vasile, M., and Pascale, P. D., “Preliminary Design of Multiple Gravity-Assist Trajectories,”Journal of Spacecraft and Rockets, Vol. 43, No. 4, 2006, pp. 794–805. https://doi.org/10.2514/1.17413

  26. [34]

    Analysis of Some Global Optimization Algorithms for Space Trajectory Design,

    Vasile, M., Minisci, E., and Locatelli, M., “Analysis of Some Global Optimization Algorithms for Space Trajectory Design,” Journal of Spacecraft and Rockets, Vol. 47, No. 2, 2010, pp. 334–344. https://doi.org/10.2514/1.45742

  27. [35]

    A global optimization method for the design of space trajectories,

    Addis, B., Cassioli, A., Locatelli, M., and Schoen, F., “A global optimization method for the design of space trajectories,” Computational Optimization and Applications, Vol. 48, No. 3, 2011, pp. 635–652. https://doi.org/10.1007/s10589-009-9261-6

  28. [36]

    Global Search of Optimal Spacecraft Trajectories using Amortization and Deep Generative Models,

    Beeson, R., Li, A., and Sinha, A., “Global Search of Optimal Spacecraft Trajectories using Amortization and Deep Generative Models,” , 2024. URL https://arxiv.org/abs/2412.20023

  29. [37]

    Global optimization by basin-hopping and the lowest energy structures of Lennard-Jones clusters containing up to 110 atoms,

    Wales, D. J., and Doye, J. P., “Global optimization by basin-hopping and the lowest energy structures of Lennard-Jones clusters containing up to 110 atoms,”The Journal of Physical Chemistry A, Vol. 101, No. 28, 1997, pp. 5111–5116. https://doi.org/10.1021/jp970984n

  30. [38]

    Globaloptimizationonfunnelinglandscapes,

    Leary,R.H.,“Globaloptimizationonfunnelinglandscapes,” JournalofGlobalOptimization ,Vol.18,No.4,2000,pp.367–383. https://doi.org/10.1023/A:1026500301312

  31. [39]

    Tuning monotonic basin hopping: improving the efficiency of stochastic search as applied to low-thrust trajectory optimization,

    Englander, J. A., and Englander, A. C., “Tuning monotonic basin hopping: improving the efficiency of stochastic search as applied to low-thrust trajectory optimization,”International Symposium on Space Flight Dynamics, Laurel, MD, 2014

  32. [40]

    Automated solution of the low-thrust interplanetary trajectory problem,

    Englander, J. A., and Conway, B. A., “Automated solution of the low-thrust interplanetary trajectory problem,”Journal of Guidance, Control, and Dynamics, Vol. 40, No. 1, 2017, pp. 15–27. https://doi.org/10.2514/1.G002124

  33. [41]

    HoppingwithanAdaptiveHopProbabilityDistribution,

    Englander,A.,Englander,J.,andCarter,M.,“HoppingwithanAdaptiveHopProbabilityDistribution,” AAS/AIAAAstrodynamics Specialist Conference, South Lake Tahoe, CA, 2020

  34. [42]

    DynamicallyLeveragedAutomated(N)MultibodyTrajectory Optimization (DyLAN),

    Beeson,R.,Sinha,A.,Jagannatha,B.,Bunce,D.,andCarroll,D.,“DynamicallyLeveragedAutomated(N)MultibodyTrajectory Optimization (DyLAN),”AAS/AIAA Astrodynamics Specialist Conference, Columbia River Gorge, Stevenson, WA, 2022

  35. [43]

    SNOPT: An SQP Algorithm for Large-Scale Constrained Optimization,

    Gill, P. E., Murray, W., and Saunders, M. A., “SNOPT: An SQP Algorithm for Large-Scale Constrained Optimization,”SIAM Review, Vol. 47, No. 1, 2005, pp. 99–131. https://doi.org/10.1137/S0036144504446096

  36. [44]

    Robust Preliminary Design For Multiple Gravity Assist Spacecraft Trajectories,

    Ellison, D. H., “Robust Preliminary Design For Multiple Gravity Assist Spacecraft Trajectories,” Ph.D. thesis, University of Illinois at Urbana-Champaign, Graduate College, Urbana, Illinois, 2007

  37. [45]

    Accelerating Robust Low-Thrust Trajectory Design with Analytic Derivatives,

    Sinha, A., and Beeson, R., “Accelerating Robust Low-Thrust Trajectory Design with Analytic Derivatives,”AAS/AIAA Astrodynamics Specialist Conference, Kaui, HI, 2025

  38. [46]

    AutomatedInterplanetaryMissionPlanning,

    Englander,J.,Conway,B.,andWilliams,T.,“AutomatedInterplanetaryMissionPlanning,” AAS/AIAAAstrodynamicsSpecialist Conference, 2012. https://doi.org/10.2514/5.9781624102714.0669.0706. 37

  39. [47]

    Ancillary data services of NASA’s Navigation and Ancillary Information Facility,

    Acton, C. H., “Ancillary data services of NASA’s Navigation and Ancillary Information Facility,”Planetary and Space Science, Vol. 44, No. 1, 1996, pp. 65–70. https://doi.org/10.1016/0032-0633(95)00107-7

  40. [48]

    Impulsive and low-thrust transfer design between stable and nearly-stable periodic orbits in the restricted problem,

    Pritchett, R., Zimovan, E., and Howell, K., “Impulsive and low-thrust transfer design between stable and nearly-stable periodic orbits in the restricted problem,”28th AIAA/AAS Space Flight Mechanics Meeting, Kissimmee, FL, 2018

  41. [49]

    Earth-Moon Near Rectilinear Halo and Butterfly Orbits for lunar surface exploration,

    Whitley, R. J., Davis, D. C., Burke, L. M., McCarthy, B. P., Rolfe, J. A., Power, M. L., and Howell, K. C., “Earth-Moon Near Rectilinear Halo and Butterfly Orbits for lunar surface exploration,”AAS/AIAA Astrodynamics Specialist Conference, Big Sky, MT, 2018

  42. [50]

    LowThrustCis-LunarTransfersUsing a 40 kW-Class Solar Electric Propulsion Spacecraft,

    Mcguire,M.,Burke,L.,Mccarty,S.,Hack,K.,Whitley,R.,Davis,D.,andOcampo,C.,“LowThrustCis-LunarTransfersUsing a 40 kW-Class Solar Electric Propulsion Spacecraft,”AAS/AIAA Astrodynamics Specialist Conference, San Antonio, TX, 2017

  43. [51]

    Low Energy Ballistic Lunar Transfers,

    Parker, J., “Low Energy Ballistic Lunar Transfers,” Ph.D. thesis, University of Colorado, Department of Aerospace Engineering Sciences, University of Colorado, 2007

  44. [52]

    Modeling a Low-Energy Ballistic Lunar Transfer Using Dynamical Systems Theory,

    Parker, J., and Born, G., “Modeling a Low-Energy Ballistic Lunar Transfer Using Dynamical Systems Theory,”Journal of Spacecraft and Rockets, Vol. 45, No. 6, 2008, pp. 1269–1281. https://doi.org/10.2514/1.35262

  45. [53]

    Monthly Variations of Low-Energy Ballistic Transfers to Lunar Halo Orbits,

    Parker, J., “Monthly Variations of Low-Energy Ballistic Transfers to Lunar Halo Orbits,”AAS/AIAA Astrodynamics Specialist Conference, Toronto, Canada, 2010

  46. [54]

    A Survey of Ballistic Transfers to Low Lunar Orbit,

    Parker, J., Anderson, R., and Peterson, A., “A Survey of Ballistic Transfers to Low Lunar Orbit,”21st AIAA/AAS Space Flight Mechanics Meeting, New Orleans, LA, 2011

  47. [55]

    Eclipse-Conscious Transfer to Lunar Gateway Using Ephemeris- Driven Terminal Coast Arcs,

    Singh, S., Junkins, J., Anderson, B., and Taheri, E., “Eclipse-Conscious Transfer to Lunar Gateway Using Ephemeris- Driven Terminal Coast Arcs,”Journal of Guidance, Control, and Dynamics, Vol. 44, No. 11, 2021, pp. 1972–1988. https://doi.org/10.2514/1.G005920

  48. [56]

    Low Thrust Trajectory Optimization for Transporting Gateway’s Power and Propulsion Element to a Near-Rectilinear Halo Orbit,

    Pascarella, A., and Woollands, R., “Low Thrust Trajectory Optimization for Transporting Gateway’s Power and Propulsion Element to a Near-Rectilinear Halo Orbit,”33rd Space Flight Mechanics Conference, Austin, TX, 2023

  49. [57]

    Orbit Maintenance and navigation of human spacecraft at cislunar Near Rectilinear Halo Orbits,

    Davis, D., Bhatt, S., Howell, K., Jang, J.-W. J., Whitley, R., Clark, F., Guzzetti, D., Zimovan, E., and Barton, G., “Orbit Maintenance and navigation of human spacecraft at cislunar Near Rectilinear Halo Orbits,”AAS/AIAA Astrodynamics Specialist Conference, San Antonio, TX, 2017

  50. [58]

    Stationkeeping Analysis for Spacecraft in Lunar Near Rectilinear Halo Orbits,

    Guzzetti, D., Zimovan, E., Howell, K., and Davis, D., “Stationkeeping Analysis for Spacecraft in Lunar Near Rectilinear Halo Orbits,”27th AAS/AIAA Spaceflight Mechanics Meeting, San Antonio, TX, 2017

  51. [59]

    The use of vertical instability of L1 and L2 planar Lyapunov orbits for transfers from near rectilinear halo orbits to planar distant retrograde orbits in the Earth-Moon system,

    Oshima, K., “The use of vertical instability of L1 and L2 planar Lyapunov orbits for transfers from near rectilinear halo orbits to planar distant retrograde orbits in the Earth-Moon system,”Celestial Mechanics and Dynamical Astronomy, Vol. 131, No. 3, 2019, p. 14. https://doi...

  52. [60]

    Transfers from distant retrograde orbits to low lunar orbits,

    Zhang, R., Wang, Y., Zhang, H., and Zhang, C., “Transfers from distant retrograde orbits to low lunar orbits,”Celestial Mechanics and Dynamical Astronomy, Vol. 132, No. 8, 2020, p. 41. https://doi.org/10.1007/s10569-020-09982-4

  53. [61]

    Transfers from near-rectilinear halo orbits to low-perilune orbitsandtheMoon’ssurface,

    Trofimov, S., Shirobokov, M., Tselousova, A., and Ovchinnikov, M., “Transfers from near-rectilinear halo orbits to low-perilune orbitsandtheMoon’ssurface,” ActaAstronautica,Vol.167,2020,pp.260–271. https://doi.org/10.1016/j.actaastro.2019.10.049

  54. [62]

    Recovery From Missed Thrust During Low Thrust Insertion Of NASA’s Gateway Into A Near Rectilinear Halo Orbit,

    Karn, S. N., McCarty, S. L., and L., M. M., “Recovery From Missed Thrust During Low Thrust Insertion Of NASA’s Gateway Into A Near Rectilinear Halo Orbit,”AAS/AIAA Astrodynamics Specialist Conference, Broomfield, CO, 2024

  55. [63]

    Options for Staging Orbits in Cis-Lunar Space,

    Whitley, R., and Martinez, R., “Options for Staging Orbits in Cis-Lunar Space,”2015 IEEE Aerospace Conference, Big Sky, MT, 2015

  56. [64]

    GatewayDestinationOrbitModel: AContinuous15YearNRHOReferenceTrajectory,

    Lee,D.,“GatewayDestinationOrbitModel: AContinuous15YearNRHOReferenceTrajectory,”TechnicalReport20190030294, NASA Johnson Space Center, 08 2019. URL https://ntrs.nasa.gov/api/citations/20190030294/downloads/20190030294.pdf. 39

  57. [2008]

    https://doi.org/10.2514/6.2008-5286

Pith tools

Reviewed August 10, 2026 · model on record in the stance chip above.