Mass Driver Track Assembly
TL;DR
- Purpose: Final assembly of Mass Driver from ready-made components
- Length: 1 km (base)*, 2-3 km for reduced g
- Time: ~5-6 weeks for first MD (with pipelining), ~3-4 weeks for subsequent
- Robots: Peak 50 robots (Moles, Centaurs, Crabs)
*For reduced loads: 2 km (637g) or 3 km (425g).
Overview
Track assembly is the final stage of Mass Driver production, when ready-made components (rails, coils, frame) are installed into a single 1 km structure.
Assembly Stages
Complete Sequence
| Stage | Time | Robots | Work |
|---|---|---|---|
| 1. Site preparation | 1 week | 10 Centaur-M | Leveling, marking |
| 2. Trench excavation (1 km) | 1 month | 20 Mole-M | Regolith excavation |
| 3. Sulfur-concrete support installation | 1 week | 10 Centaur-M | 100 supports every 10 m |
| 4. Frame installation | 2 weeks | 20 Centaur-M | ~85 truss sections |
| 5. Rail laying | 1 week | 10 Centaur-M | 100 segments of 10 m |
| 6. Coil mounting | 2 weeks | 10 Centaur-M | 1000 coils |
| 7. Power cable routing | 1 week | 10 Centaur-M | Coil power supply |
| 8. Cooling connection | 3 days | 5 Centaur-M | NaK circuit |
| 9. Electronics installation | 1 week | 10 Centaur-M | Sensors, controllers |
| 10. Calibration and testing | 3 days | 5 Centaur-M | Geometry, tests |
| TOTAL | ~5-6 weeks* | peak 50 |
*With parallel pipelining: stages 3-9 begin on completed trench sections while excavation continues ahead. Critical path ≈ trench duration + finishing work on last section.
With experience (subsequent MDs): ~3-4 weeks
Stage Details
1. Site Preparation
| Work | Description |
|---|---|
| Route selection | Along the terminator (day/night boundary) |
| Geodetic marking | Laser leveling, accuracy ±5 mm |
| Leveling | Moles cut regolith mounds |
| Base preparation | Installation of temporary structures |
Route requirements: - Straight line (deviation <1 mm per 100 m) - Slope <0.1% (0.38g gravity is not critical) - Distance from craters >500 m (safety)
2. Trench Excavation
20 Mole-M robots dig a 1 km trench.
| Parameter | Value |
|---|---|
| Trench width | 6 m |
| Depth | 3 m |
| Excavation volume | 18,000 m³ regolith |
| Mole productivity | 100 t/day = ~35 m³/day |
| Time for 1 Mole | ~514 days |
| Time for 20 Moles | ~26 days ≈ 1 month |
Details: Mole-M Robots
3. Sulfur-Concrete Support Installation
100 sulfur-concrete supports every 10 m to support the frame.
| Parameter | Value |
|---|---|
| Supports | 100 |
| Support mass | 1 t sulfur-concrete |
| Foundation depth | 2-3 m |
| Time per support | 1 hour |
| TOTAL | 100 hours = 1 week (10 robots) |
Sulfur-concrete — construction material using sulfur (S) as binder and regolith as aggregate. Requires no water. Sulfur melts at 115°C, forming a strong structure upon solidification.
4. Frame Installation
Truss sections are placed on supports and welded.
| Parameter | Value |
|---|---|
| Frame sections | ~85 (12 m each) |
| Section mass | ~3 t |
| Installation time per section | 2 hours (lifting + welding) |
| TOTAL | ~170 hours = 2 weeks (20 robots) |
Details: Tunnel Frame
5. Rail Laying
Aluminum rails are mounted on the frame.
| Parameter | Value |
|---|---|
| Rail segments | 100 (10 m each, 2 rails) |
| Segment mass | ~0.7 t |
| Laying time per segment | 1 hour |
| Joint welding | 10 min per joint |
| TOTAL | ~130 hours = 1 week (10 robots) |
Details: Rail Production
6. Coil Mounting
1000 coils are installed along the track.
| Parameter | Value |
|---|---|
| Coils | 1000 |
| Installation time per coil | 15 min |
| TOTAL | 250 hours = 2 weeks (10 robots) |
Details: Coil Winding
7. Power Cable Routing
Power supply for coils from the energy system.
| Parameter | Value |
|---|---|
| Cable length | ~3 km (main + branches) |
| Cross-section | 100-200 mm² Al |
| Cable mass | ~10 t |
| Routing time | 1 week (10 robots) |
8. Cooling Connection
NaK circuit for cryogenic cooling.
| Parameter | Value |
|---|---|
| NaK pipe length | ~2 km |
| Diameter | Ø20 mm |
| Radiators | ~5,000 m² (directed into shadow) |
| Connection time | 3 days (5 robots) |
9. Electronics Installation
Sensors, controllers, control systems.
| Parameter | Value |
|---|---|
| Control units | 34 (every 30 m) |
| Sensors | 2,150 (current, temperature, position, vibration) |
| Cameras | 20 (track monitoring) |
| Installation time | 1 week (10 robots) |
Details: Control Electronics
10. Calibration and Testing
Final check before launch.
| Test | Description |
|---|---|
| Track geometry | Laser leveling, accuracy ±0.5 mm |
| Electrical circuits | Ohmmeter, insulation, inductance |
| Cooling | NaK circuit test, temperature -150°C |
| Test shot (empty) | Empty container acceleration |
Time: 3 days
Details: Testing
Material Balance
Per 1 MD (1 km):
| Component | Mass | Source |
|---|---|---|
| Frame (steel) | ~270 t | Regolith Processing |
| Rails (aluminum) | ~70 t | Regolith Processing |
| Coils (aluminum) | ~100 t | Regolith Processing |
| Radiators (aluminum) | ~50 t | Regolith Processing |
| NaK coolant | ~5 t | Local |
| Electronics | ~6 t | Mostly Earth Import |
| TOTAL (MD) | ~500 t | ~99% local |
| Sulfur-concrete (supports) | ~100 t | Local (regolith + sulfur) |
| TOTAL installed | ~600 t |
With extension: 2 km (~875 t MD), 3 km (~1,300 t MD).
Construction Logistics
| Transport | Robots | Role |
|---|---|---|
| Component delivery to site | 10 Crab-M | Material trailers |
| Heavy section installation | 20 Centaur-M | Cranes, manipulators |
| Welding and fastening | 10 Centaur-M | Welding robots |
| Cable routing | 10 Centaur-M | Cable pulling |
See Also
- Rail Production — aluminum guides
- Coil Winding — electromagnetic windings
- Tunnel Frame — steel structure
- Control Electronics — control systems
- Testing — final check