Transportation Sector

Purpose: The TransportationSector is the logistics backbone of the simulation, managing the entire lifecycle of interplanetary transport. It orchestrates a fleet of reusable rockets, handles the production of rocket fuel from local resources (Helium-3), and processes transport requests to move equipment and materials between Earth and the Moon.

Core Components:

  • Rocket: A reusable agent capable of round-trip missions. Each rocket has a specific payload capacity and fuel efficiency. Its internal state machine manages its availability and mission progress (outbound flight, loading on the Moon, inbound flight).

  • FuelGenerator: An agent that simulates an advanced fusion-based reactor. It consumes Helium-3 (He3_kg) to generate power, which is then used to produce rocket propellant.

  • TransportRequest: A data object representing a single logistics mission, detailing the payload, origin, destination, and requesting sector.

Operational Cycle & Key Algorithms

The sector’s operation is a continuous loop of fuel production, request processing, and mission management.

1. Fuel Production Pipeline The sector aims to be self-sufficient by producing its own fuel.

  • A. Proactive He-3 Request (_request_resources_for_fuel): If the sector’s internal stock of rocket fuel and He-3 fall below configured minimums, it automatically publishes a resource_request to the event bus to acquire more He-3. This ensures a steady supply of raw material for fuel generation.

  • B. Fuel Generation (_generate_fuel): In every step, the sector tasks its FuelGenerators to convert available He-3 into rocket fuel, which is added to its rocket_fuel_kg stock.

2. Launch Processing (_process_transport_queue) The sector processes pending transport requests in a Last-In-First-Out (LIFO) order.

  • A. Find Available Rocket: It scans its fleet for a Rocket that is currently is_available.

  • B. Pre-Launch Calculation (_attempt_launch): For an available rocket and a pending request, it performs a critical check:

    1. It calculates the total propellant required for a round trip based on the payload mass.

    2. It compares the required fuel against its current rocket_fuel_kg stock.

  • C. Launch or Defer:

    • If fuel is sufficient: The rocket is launched. The required fuel is deducted from the sector’s stock, and the rocket’s commit_round_trip method is called. The rocket becomes unavailable, and its internal mission timer begins.

    • If fuel is insufficient: The launch is deferred. The request remains in the queue, and the sector will attempt to launch it again in a future step once more fuel has been generated.

3. Mission Progression (_step_all_rockets) In every simulation step, the sector calls the step() method on every rocket in its fleet.

  • This advances the internal state machine of any rocket currently on a mission.

  • When a rocket arrives at its destination (either the Moon or Earth), it publishes a payload_delivered event, notifying the relevant sector that its requested equipment or resources have arrived.

  • Upon returning to its origin, the rocket’s mission is cleared, and it becomes is_available for a new task.

Equations

Fuel Generation: The amount of propellant generated \(P_{\text{gen}}\) from a given amount of Helium-3 \(He3_{\text{proc}}\) is calculated as:

\[\text{kWh}_{\text{avail}} = (He3_{\text{proc}} \times \text{GWh}_{\text{thermal}} \times 10^6) \times \eta_{\text{efficiency}}\]
\[P_{\text{gen}} = \frac{\text{kWh}_{\text{avail}}}{\text{kWh}_{\text{per\_kg\_prop}}}\]

Where:

  • \(\text{GWh}_{\text{thermal}}\) is the thermal energy per kg of He-3.

  • \(\eta_{\text{efficiency}}\) is the generator’s conversion efficiency.

  • \(\text{kWh}_{\text{per\_kg\_prop}}\) is the energy needed to create 1 kg of propellant.

Rocket Fuel Calculation:

The propellant needed for a round trip \(P_{\text{total}}\) is the sum of the outbound and return legs.

\[P_{\text{outbound}} = \text{Payload}_{\text{outbound\_kg}} \times \text{Usage}_{\text{prop\_per\_kg}}\]
\[P_{\text{return}} = \text{Payload}_{\text{return\_kg}} \times \text{Usage}_{\text{prop\_per\_kg}}\]
\[P_{\text{total}} = P_{\text{outbound}} + P_{\text{return}}\]

Configuration Options

The sector is configured in the world_system JSON file, defining its fleet, fuel generators, and operational parameters. If flight_distance is omitted, the sector uses the shared FLIGHT_DISTANCE_KM lookup table in world_system_defs.py.

"transportation": {
  "sector_name": "transportation",
  "flight_distance": 384400,
  "loading_time_steps": 24,
  "he3_request_threshold_kg": 1.0,
  "minimum_fuel_k_sp": 5000,
  "rockets": [
    {
      "template_id": "comp_rocket",
      "quantity": 3,
      "config": {
        "prop_usage_kg_per_payload_kg": 21.4,
        "carrying_capacity_equipment": 22800
      },
      "metric_contributions": [
        { "metric_id": "IND-DUST-COV", "value": 0.1 }
      ]
    }
  ],
  "fuel_generators": [
    {
      "template_id": "comp_fuel_gen_rocket",
      "quantity": 1
    }
  ]
}

TODO: Potential Improvements

  • [ ] Implement Realistic Power Demand: The get_power_demand() method is a placeholder. The FuelGenerators should consume significant power from the grid when operating.

  • [ ] Refine Payload Weight Calculation: The weight for return payloads is currently a placeholder (sum(values) * 20). This should be replaced with a data-driven model that maps equipment types to their actual mass.

  • [ ] Implement Queue Prioritization: The transport queue is processed Last-In-First-Out (LIFO). A more robust system would allow for request prioritization based on urgency or the importance of the payload.

  • [ ] Standardize Metric Contributions: The metric contribution logic should be updated to use the plural metric_contributions and handle a list of contributions, consistent with other sectors.

  • [ ] Add Dynamic Fleet Expansion: The sector should listen for module_completed events to dynamically add new rockets and fuel generators to its fleet as they are constructed.