13Train computers — 2 AI modules, SIL 4 controlStructure
14Line converter — catenary to DC linkPower
15DC link — 3 kV, every source on one busPower
16Pinion & bull gear — 4.7:1, every axleTraction
17Air reservoirs & ECP brake riggingStructure
II · Power & drivetrain
Hydrogen, battery and wire on one DC link.
Twelve fuel-cell modules, a 2 MWh battery and a pantograph feed one 3 kV DC link. Six inverters draw from it, one per axle. Braking energy returns to the battery before any reaches the grids.
Power bay — rotating view
Three fuel-cell banks of four modules, each with a turbo air compressor spinning on top; the 2 MWh battery and the six axle inverters at right; three radiator fans on the roof block. Four of the twelve hydrogen cylinders ride above. One 3 kV DC link bar runs under all of them.
01Hydrogen cylinders — 4 of 12 drawn, 50 kg each at 700 bar
02Fuel-cell modules — 12 × 500 kW net in 3 banks, 55%
03Air compressors — 3 × 100 kW turbo, one per bank
Five weeks on about thirty stations. The underframe is welded while the bogie frames are built beside it; the motors hang on their axles and the bogies roll under; the fuel-cell banks, battery and inverters are craned in; the shell, roof tanks and pantograph close it; sensors go on and the locomotive is load-tested and run on track.
The underframe is welded on stands while the bogie frames are built alongside.
Each motor hangs on its axle; the bogies roll under and the frame lowers.
Fuel-cell banks, battery and inverters are craned in and bolted to one bus.
The cab-less shell closes over the bay; tanks and pantograph go on top.
Sensors are calibrated, the plant is load-tested, then the locomotive runs on track.
I
Underframe welded, bogie frames built
II
Motors hung, bogies rolled under
III
Power bay modules craned in
IV
Carbody, roof tanks, pantograph
V
Sensors fitted, tested on track
IV · Specification
Design specification.
Design targets for the autonomous road locomotive.
Power
6 MW
Traction motors
6 × 1 MW, axle-hung
Fuel cells
12 × 500 kW, 55%
Hydrogen aboard
600 kg at 700 bar
Consumption
≈ 330 kg H₂ / hr at full power
Endurance
≈ 6 hr at average load
Refuel
20 min at hub stations
Battery
2 MWh, 6 MW regenerative
Catenary
25 kV AC via pantograph
Starting tractive effort
850 kN
Top speed
120 km / h
Axle load
32 t · 6 axles
Weight
192 t
Length
22.7 m over couplers
Metal content
≈ 90%
Crew
0
Onboard compute
Two AI modules watch two kilometres ahead; a SIL 4 computer holds the train
Modules2 AI modules (module 1: forward path and driving; module 2: train, cars and verification) + 1 SIL 4 train-control computer
AI throughput10,000 TOPS total (2 × 5,000, INT8 / FP4 sparse)
Memory2 × 128 GB LPDDR6 at 600 GB/s per module; 4 TB solid-state event recorder
Power draw236 W compute; ≈ 0.5 kW with cameras, lidars, radars and switches — 0.01% of the 6 MW plant
Process node2 nm-class SoC; SIL 4 computer on a mature 16 nm node, 15-year supply. Compute is a line-replaceable unit, swapped at mid-life
RedundancyEvery sensor is wired to both modules. Each module is primary for its zone and hot standby for the other; both must agree to keep speed. The SIL 4 computer (three safety controllers voting two out of three) holds speed, braking and signals, and stops the train with no AI module running.
Sensors8 long-range cameras (6 visible 4K, 2 thermal; 2 km), 3 long-range lidars, 2 radars, aggregated over automotive Ethernet into both modules; bearing, wheel and brake data from every car over the ECP trainline
Safety sensorsThe SIL 4 channel reads its own: 2 axle tachometers, a Doppler ground-speed radar, brake-pipe and brake-cylinder pressure transducers, GNSS and wayside transponder readers, a safety-rated obstacle radar
LinkTrackside radio, corridor 5G and low-orbit satellite, ≈ 1 Mbit/s used; the train plan comes from The Brain and is held aboard
A freight train at 120 km/h needs about a kilometre to stop, so the modules watch two kilometres ahead and must agree to keep speed. Commands pass from the train agent through the SIL 4 channel to the axle inverters and brakes, and reach them no other way. Each axle inverter closes its current loop at 1 kHz on its own. A software fault can never drive the locomotive outside its certified safe envelope.
Today vs IC
Power and operation: today’s road locomotive beside the IC design
Power4,400 hp (3.3 MW) V12 diesel → alternator → 6 AC motors of ≈ 540 kW6 MW: 12 fuel-cell modules, a 2 MWh battery and a pantograph on one 3 kV DC link → 6 × 1 MW motors
Fuel5,000 US gal of diesel; ≈ 210–220 gal/hr at full power600 kg of hydrogen at 700 bar; ≈ 330 kg/hr at full power; water is the only exhaust
Endurance70–100 hr on a full tank≈ 6 hr at average load, refuelled in 20 min at hubs; no limit under wire
BrakingDynamic brake up to 98,000 lbf; the energy is burned in gridsRegenerative: up to 6 MW back into the battery; grids only when it is full
CrewCab; two crew required by federal ruleNo cab. Zero crew: 2 AI modules and a SIL 4 train-control computer
Size22.7 m (74 ft 6 in), 196 t (432,000 lb)22.7 m, 192 t
The IC column is the design shown on this page. Sources for the Today column are listed in BUILD_NOTES.md.
Runs on The Brain
Every train is planned by The Brain’s orchestration layer, mirrored in the network’s digital twin, and re-planned the moment reality drifts.