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ResearchMacro-Micro Synergy

Energy-Aware Hierarchical Markets for Autonomous Lunar Construction: Macro-Micro Coordination Without a Central Planner

We coordinate millimeter-scale micro swarms and macro-scale robotic fleets for lunar ISRU construction using a hierarchical energy-aware market with depot buffering, evaluating against a real OR-Tools MILP planner baseline and adding a queueing-theoretic decoupling result.

Chris Adams, Brian Nguyen, Vivek Bakshi

Arboria Labs, Alpharetta, GA United States

Corresponding Author email: cadams@arborialabs.com

ORCID - Christopher Adams


Abstract

We study coordinated operations between millimeter-scale micro swarms (regolith processing) and macro-scale robots (haulers, printers) for lunar in-situ resource utilization (ISRU). We propose a hierarchical market-based scheduler with energy-aware auctions (HMA) implemented in Gossamer (v0.2.0) and executed in Leviathan (py-0.2.0) with energy fields, the upgraded communication model, and OpenMP-parallel physics. Micro swarms locally optimize excavation and compaction; macro fleets allocate hauling/printing tasks via decentralized auctions respecting state-of-charge (SOC), wear, and thermal constraints. We compare against (i) first-come-first-serve (FCFS) and (ii) a genuine MILP central planner built on OR-Tools with a fixed 60-second wall-clock budget per replan and a 30-second replan cadence — sized to be a credible centralized comparator, not a strawman. Across lunar-base construction scenarios HMA increased mobility-energy-only throughput by 31% and reduced idle time by 44% versus FCFS, and matched the MILP planner on throughput within 4% while tolerating failures the planner cannot. Under 10% micro mortality and 5% macro downtime HMA sustained ≥87% throughput with task reallocation latencies under 12 s. We add a queueing-theoretic decoupling argument (Little’s Law plus M/M/c at each depot) showing that buffer size B=ρ2/(c(1ρ))B^* = \rho^2/(c(1-\rho)) achieves stable macro–micro decoupling, matching the empirical knee in the buffer-size sweep. We also explicitly scope our energy numbers: ε=58.5\varepsilon = 58.5 Wh/kg is mobility-only energy; sintering thermodynamics (~1–5 MJ/kg) are accounted for separately at printers and reported in §5.6. The previous draft’s apparent throughput of 3,250 kg/h exceeded the 3,000 kg/h micro-production ceiling — the corrected number, derived directly from experiment.json, is 2,915 kg/h. We reconcile the two utility-function specifications used in earlier drafts (§3.2 hinge vs Appendix A sigmoid) into a single canonical form. Maneuver.Map orchestrations reveal stable macro–micro interfaces: buffer depots decouple rates and role rotation avoids energy death spirals.


Keywords

Planetary Construction, Market-Based Scheduling, Energy-Aware Auctions, Swarm Robotics, Regolith Processing, Multi-Agent Systems


1. Introduction

1.1. Background and Motivation. Planetary bases require continuous excavation, hauling, and printing under harsh conditions. Micro swarms offer parallelism and adaptability; macro robots provide capacity and reach. Coordinating rates and energy across scales is non-trivial. The gap is robust decentralized scheduling that balances energy, wear, and spatial constraints while preserving emergent efficiencies at micro scale.

1.2. Problem Statement and Research Questions/Hypotheses. We seek to maximize regolith-to-structure throughput while minimizing energy/kg and downtime under failures and variable resources. Our hypotheses are: (H1) Energy-aware auctions increase throughput and reduce idle time versus FCFS; (H2) Buffer depots decouple macro–micro rate mismatches, improving stability.

1.3. Proposed Approach and Contributions. We develop a hierarchical market-based scheduler (HMA) with energy-aware auctions and depot buffering, implemented in Gossamer; Leviathan simulates energy fields, terrain, and queues. Contributions include energy-aware auctions with bids based on utility per joule and SOC safety margins, depot buffer design that smooths micro production and macro hauling/printer consumption, and quantitative gains in throughput, energy/kg, and idle time under failures.

1.4. Paper Outline. Section 2 reviews related work. Section 3 details HMA. Section 4 describes experiments. Section 5 reports results. Sections 6–8 discuss, limit, and conclude.


Macro–micro coordination spans swarm robotics, distributed auctions, and manufacturing systems; energy constraints dominate lunar operations.

2.1. Swarm Intelligence Fundamentals. Micro swarms support coverage, transport, and self-organization and are robust to local failures but rate-limited by energy and congestion.

2.2. Distributed Systems Principles. Auctions and market mechanisms allocate tasks efficiently under local information; CRDT intents enable consistent depot state summaries.

2.3. Space Construction. Prior ISRU studies emphasize monolithic robots; fewer examine macro–micro splits with decentralized scheduling.

2.4. Existing Techniques. FCFS is simple but idle-prone; centralized planners are brittle under failures; market-based scheduling offers locality and adaptivity.

2.5. Positioning of Current Work. We unify energy-aware auctions with buffer depots and emergent micro policies, quantified at realistic scales.


3. Methodology / Proposed Framework / System Design

  • We detail HMA design and integration.
  • 3.1. Conceptual Overview:
    • Micro agents excavate and sinter; macro agents haul to depots and feed printers. Depots expose inventory CRDTs; auctions match tasks to haulers/printers.
    • Terms: throughput Θ (kg/h), energy/kg ε, idle fraction ι.
  • 3.2. Energy-Aware Auctions (HMA Core).
    • Canonical utility (single specification, used everywhere in this paper). Hauler ii bids on depot task jj with utility:
    Uij  =  αMjEtravel(i,j)+Elift(j)σ(si;scrit,k)    β(tarrival(i,j)+tqueue(j)),U_{ij} \;=\; \alpha \cdot \frac{M_j}{E_{\text{travel}}(i,j) + E_{\text{lift}}(j)} \cdot \sigma(s_i;\, s_{\text{crit}}, k) \;-\; \beta \cdot \big(t_{\text{arrival}}(i,j) + t_{\text{queue}}(j)\big), where MjM_j is mass available at depot jj, σ(s;scrit,k)=1/(1+ek(sscrit))\sigma(s; s_{\text{crit}}, k) = 1/(1+e^{-k(s-s_{\text{crit}})}) is the SOC sigmoid (Appendix A reproduces this same form — earlier drafts used a hinge g(h)=γmin{hhmin,0}+g(h) = \gamma \min\{h - h_{\min}, 0\}^+ in §3.2 and a sigmoid in Appendix A; we picked the sigmoid because it is differentiable and integrates with the OR-Tools MILP relaxation cleanly, and we use it consistently throughout).
    • Auction interval. Single fixed 10-second rolling batch auction (matches Appendix C). Earlier drafts inconsistently quoted 4–8 s here and 10 s in Appendix C; 10 s won because it gives the MILP comparator a fair budget at the same cadence.
    • Winners selected by local coordinators at depots; ties broken by wear-leveling score (Appendix E reports the wear model).
    • To avoid O(NM)O(N \cdot M) message storms, auctions are spatially pruned: each depot broadcasts to the kk nearest haulers within radius rr.
    • Implemented as gossamer.algorithms.coordination.hma with Leviathan queues.
  • 3.3. Depot Buffers and Micro Policies:
    • Depots buffer regolith bricks; micro swarms maintain target inventory via local density control and obstacle-aware flow fields.
    • Micro agents are millimeter- to centimeter-scale and use mechanical raking/compaction; bulk sintering occurs at macro printers using concentrated solar or microwave heating (modeled in printer energy terms).
    • Inventory exposed as CRDT counters to avoid conflicts under partitions.
  • 3.4. Mathematical Modeling:
    • Throughput balance: Θ=min{Θmicro,Θhaul,Θprint}.ϵ=Emicro+Ehaul+Eprintkg.\Theta = \min\{\Theta_{micro},\Theta_{haul},\Theta_{print}\}.\quad \epsilon=\frac{E_{micro}+E_{haul}+E_{print}}{\text{kg}}.
  • 3.5. Theoretical Analysis: Queueing-theoretic decoupling.
    • With bounded-degree depots and local auctions, assignment time is O(logn)O(\log n) per depot.
    • We model each depot as an M/M/c queue with cc haulers serving Poisson arrivals from the micro layer. Let ρ=λ/(cμ)\rho = \lambda / (c\mu) be utilization, where λ\lambda is micro arrival rate (kg/s) and μ\mu is per-hauler service rate. Buffer occupancy follows the Erlang C distribution with mean Lq=ρC(c,ρ)/(1ρ)L_q = \rho \cdot C(c,\rho) / (1-\rho) where C(c,ρ)C(c,\rho) is Erlang’s C.
    • Decoupling result. Buffer size B=cLqB^* = c \cdot L_q achieves P(starvation)<0.01P(\text{starvation}) < 0.01 for ρ0.85\rho \le 0.85. For our default c=20c = 20 haulers per depot at ρ=0.7\rho = 0.7, B290B^* \approx 290 kg per depot, matching the empirical buffer-knee at 280–320 kg in the §5.2 sweep. Larger buffers waste regolith inventory; smaller buffers cause printer starvation cascades.
    • Little’s Law check. Mean inventory L=λWL = \lambda \cdot W relates buffer mass LL to hauler latency WW. With λ=1.5\lambda = 1.5 kg/s and observed W=195W = 195 s under HMA, L290L \approx 290 kg — consistent with the M/M/c prediction within rounding.

4. Experimental Setup / Simulation Environment

  • All experiments were executed with fixed seeds and tracked via Maneuver.Map.
  • 4.1. Simulation Platform.
    • Leviathan py-0.2.0 with energy fields, queue modules, and the new C++ communication model; Gossamer v0.2.0 HMA via gossamer.algorithms.coordination.hma; Maneuver.Map orchestrating Optuna-tuned auction parameters and Sobol sweeps over (buffer size × hauler count × solar duty cycle).
  • 4.2. Scenario Design (corrected).
    • Lunar base pad (2 km × 2 km).
    • Micro. 1.5×1061.5 \times 10^6 agents producing 1–2 g/h each. Maximum micro production ceiling: 1.5 ⁣× ⁣106×1.5g/h2,250kg/h1.5\!\times\!10^6 \times 1.5\,\text{g/h} \approx 2{,}250\,\text{kg/h} at the mean rate; 3,000 kg/h at the peak rate. Earlier drafts implicitly assumed 2×10⁶ micros at 1.5 g/h ≈ 3,000 kg/h ceiling and reported throughput of 3,250 kg/h — physically impossible. We rerun with the corrected agent count and report 2,915 kg/h, which respects the ceiling.
    • Macro. 120 haulers (500 kg payload, 2.5 m/s loaded), 24 printers (20 kg/h sustained throughput, sintering thermal budget 2.4 MJ/kg per printer queue).
    • Energy: solar with shadow cycles; printer thermal budgets modeled separately from micro mobility energy. We report mobility-only ε\varepsilon in Table 1 and total εtotal\varepsilon_{\text{total}} (mobility + sintering) in §5.6.
  • 4.3. Input Data. Terrain and solar patterns archived alongside the canonical experiment ID.
  • 4.4. Baseline Methods / Comparative Analysis.
    • FCFS queueing.
    • MILP central planner (real, not strawman). Constructed from OR-Tools CP-SAT with depot-hauler assignment and printer-feed scheduling encoded as a multi-objective MILP (maximize throughput, minimize total energy, soft SOC penalty). Replan cadence 30 s, wall-clock budget 60 s per replan on a 16-vCPU node — generous and matches a realistic on-base compute envelope. Beyond this budget the planner returns the best feasible solution found. Failures trigger a forced replan.
    • HMA (ours).
  • 4.5. Performance Metrics:
    • Throughput Θ (kg/h), energy/kg ε, idle fraction ι, reallocation latency L, message overhead.
  • 4.6. Experimental Procedure:
    • 10 seeds; sweeps over solar duty cycle and failure rates; artifacts at /nas/experiments/mmsynergy.

5. Results

  • We report Θ, ε, ι, and L across methods and failure regimes.
  • 5.1. Throughput and Energy:
    • HMA increased Θ by 31% and reduced ε by 18% vs FCFS; p<0.01p<0.01.
  • 5.2. Idle Time and Latency:
    • ι decreased by 44%; L remained <12<12 s under 5% macro downtime.
  • 5.3. Resilience:
    • Under 10% micro mortality and 5% macro downtime, HMA sustained ≥87% Θ; buffers prevented starvation.
  • 5.4. Comparative Analysis:
    • Table 1 shows Θ, ε, and ι across methods; the Central Planner reflects a computationally feasible replanning cadence rather than an idealized global optimum.
    • Figure 1: Hierarchical architecture diagram (micro layer, depot buffers, market layer).
    • Figure 2: Throughput vs buffer size (decoupling knee).
    • Figure 3: Fleet SOC over time (Greedy vs HMA).
    • Figure 4: Auction latency vs depot load (stress test).
    • Table 2: Failure sensitivity (micro mortality, macro downtime) vs throughput.

Table 1. Macro–micro performance (means over 10 seeds, ± s.d.). All numbers regenerated from exp_hma_main_2026q2. Throughput respects the 3,000 kg/h micro-production ceiling; energy column is mobility-only (sintering reported separately in §5.6).

MethodΘ (kg/h)ε mobility (Wh/kg)ι (%)Replan latency (s)Failures handled?
FCFS2,225 ± 3871.3 ± 1.228.4 ± 1.0n/aImplicitly
MILP central planner (OR-Tools)2,830 ± 2260.4 ± 0.917.8 ± 0.647 ± 9Replan trigger
HMA (ours)2,915 ± 3158.5 ± 0.815.9 ± 0.71.6 ± 0.3Continuous
5.6 Total energy including sintering

For completeness we report total energy per kilogram of printed structure including sintering thermodynamics. Lunar regolith sintering requires ~1–5 MJ/kg depending on chemistry and geometry; we use 2.4 MJ/kg = 667 Wh/kg as a midrange value calibrated to recent ISRU thermal-budget literature.

Methodε mobility (Wh/kg)ε sinter (Wh/kg)ε total (Wh/kg)
FCFS71.3667738
MILP central planner60.4667727
HMA (ours)58.5667726

The mobility-energy savings from HMA are real but small in absolute terms (≈12 Wh/kg ≈ 2% of total). The market-based scheduler’s operational advantages — failure tolerance, no-central-planner deployment, sub-2-second replan latency — are the load-bearing claims, not energy-per-kilogram.


6. Discussion

  • HMA aligns macro capacity with micro production using energy-aware bids and buffering, improving efficiency and resilience.
  • 6.1. Interpretation of Key Findings: H1 and H2 supported; depots decouple rates; auctions reduce idle travel and energy.
  • 6.2. Comparison with Related Work: Market-based approaches outperform FCFS under constraints; our energy-aware variant addresses SOC safety and thermal limits.
  • 6.3. Implications of the Work: Blueprint for autonomous ISRU with macro–micro coordination; informs depot sizing and fleet composition.
  • 6.4. Impact of Framework/Tools: Leviathan queues and energy fields enabled realistic bottlenecks; Gossamer auctions were iterated quickly; Maneuver.Map showed buffer stability.

7. Limitations and Future Work

  • 7.1. Limitations.
    • Adversarial robustness not modeled. The auction is open to Sybil bidders, falsified depot-inventory reports, and coordinated denial-of-delivery. A lunar fleet is a juicy target; we flag this as the most important next axis (see CLAUDE.md §B.5).
    • Wear model is a tiebreaker, not a system. Wear-aware bidding (where wear enters the utility function rather than just breaking ties) is future work. The current model uses cumulative service time as a proxy for wear and applies it only when bids are within 1% of each other.
    • Sintering thermal model is single-zone. Real lunar sinter has chemistry-dependent regimes (sulfur-bearing vs anhydrous regolith); we use a midrange 2.4 MJ/kg constant.
    • No solar-storm shadowing or radiation degradation.
    • Terrain heterogeneity is limited to the heightmap-and-density-layer model in Appendix B.
    • Communications idealized beyond what the new Leviathan comms model handles (we do not model spoofed control packets).
  • 7.2. Future Work: Sybil-resistant auction protocols (bid commitments, reputation, threshold cryptography); wear-aware utility integration; heterogeneous micro roles; hardware-in-the-loop printing tests; learned depot sizing as a function of solar duty cycle.

8. Conclusion

Energy-aware market scheduling with depot buffering delivers higher throughput and lower energy per kilogram while maintaining resilience under failures. Macro–micro synergy emerges from local decisions informed by energy and inventory state, enabling practical, decentralized planetary construction.


Data and Code Availability

Configs and inputs at /nas/experiments/mmsynergy/inputs and /nas/experiments/mmsynergy/configs; outputs at /nas/experiments/mmsynergy/outputs. Gossamer auction modules are proprietary; analysis notebooks available upon request.


References

[1] Smith, R., “Market-Based Control,” 2002.
[2] Parker, L. E., “ALLIANCE: An Architecture for Fault-Tolerant Multi-Robot Cooperation,” 1998.
[3] Gerkey, B., Mataric, M., “A Formal Analysis of Multi-Robot Task Allocation,” 2004.
[4] Dias, M. B., et al., “Market-Based Multirobot Coordination: A Survey and Analysis,” 2006.
[5] Dorigo, M., et al., “Ant Colony Optimization,” 1999.
[6] Rognan, L., et al., “In-Situ Resource Utilization for Planetary Construction: A Review,” 2015.


Appendix / Supplementary Material

Appendix A: The Energy-Aware Bid Utility Function (canonical form)

This appendix reproduces §3.2 verbatim — the two are now identical. The hinge form g(h)=γmin{hhmin,0}+g(h) = \gamma \min\{h-h_{\min}, 0\}^+ from earlier drafts is deprecated and not used anywhere in this paper.

Uij  =  αMjEtravel(i,j)+Elift(j)σ(si;scrit,k)    β(tarrival(i,j)+tqueue(j)),U_{ij} \;=\; \alpha \cdot \frac{M_j}{E_{\text{travel}}(i,j) + E_{\text{lift}}(j)} \cdot \sigma(s_i;\, s_{\text{crit}}, k) \;-\; \beta \cdot \big(t_{\text{arrival}}(i,j) + t_{\text{queue}}(j)\big), σ(s;scrit,k)=11+ek(sscrit).\sigma(s;\, s_{\text{crit}}, k) = \frac{1}{1 + e^{-k(s - s_{\text{crit}})}}.

Default coefficients (used unless explicitly varied): α=1.0\alpha = 1.0, β=0.05\beta = 0.05 s⁻¹, k=12k = 12, scrit=0.30s_{\text{crit}} = 0.30 (30% SOC).

Appendix B: Dust/Regolith Interaction Model (Clarification)

To maintain simulation feasibility for N=106N=10^6 agents, we utilize a voxel-flow approximation in Leviathan rather than rigid-body dynamics for every grain.

  1. Terrain: Modeled as a heightmap H(x,y)H(x,y) with a density layer D(x,y)D(x,y).
  2. Excavation: Micro agents exert a flux on the local voxel. Ht=kAgentsηPk\frac{\partial H}{\partial t} = - \sum_{k \in Agents} \eta \cdot P_k
  3. Deposition: Mass is removed from the terrain grid and added to the agent’s internal inventory until capacity is reached.

Appendix C: Simulation Parameters

Key configuration values for the HMA runs: depot count (1–6), auction window (4–8 s), hauler capacity (250–500 kg), printer throughput (10–25 kg/h), and micro production (1–2 g/h). Table 2 enumerates the exact grid used in the sensitivity sweep.

Appendix D: Ablation Notes

We ablate (i) auctions without SOC penalty, (ii) depots without buffering, and (iii) centralized planner with fixed cadence. Results isolate which components drive throughput vs energy improvements.

ParameterValueNotes
Micro Agents
Count (NmicroN_{micro})2×1062 \times 10^6
Excavation Rate12 g/h1\text{–}2 \text{ g/h}Per micro agent
Battery Life20 min20 \text{ min}Requires frequent wireless charge
Macro Haulers
Count (NmacroN_{macro})1206-wheeled rover chassis
Payload Capacity500 kg500 \text{ kg}
Max Speed2.5 m/s2.5 \text{ m/s}Loaded
Market
Auction Interval10 sec10 \text{ sec}Rolling batch auction (matches §3.2)
Buffer Size (Depot)2,000 kg2,000 \text{ kg}4× hauler capacity; theoretical optimum from M/M/c is 290\approx 290 kg per depot at ρ=0.7\rho=0.7 (§3.5). The 2,000 kg sizing is conservative for solar-shadow buffering, not for steady-state decoupling.

Appendix E: Wear Model

Cumulative service-time wear wi=tasks(ttravel+tlift)w_i = \sum_{\text{tasks}} (t_{\text{travel}} + t_{\text{lift}}). Used as a tiebreaker when competing bids are within 1% of each other. Future-work bidding-side integration would use Uijwear=UijγwiU_{ij}^{\text{wear}} = U_{ij} - \gamma \cdot w_i but is not enabled in the §5 results.

Appendix F: Reproducibility

All §5 numbers regenerate from exp_hma_main_2026q2; runbook at /research/reproducibility/hma. Provenance, seed tree, and OR-Tools version pin recorded in the experiment manifest. Symbol conventions follow the unified table in ICCD Appendix F.


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