Manufacturing line/Rail systems/Double-stack well car
Autonomous · Rail systems

Double-stack well car

Six 53-foot boxes on three wells. Every car brakes at once and reports every bearing.

Phase 6 · 2033+Concept design
Capacity
6 × 53 ft
Payload
165 t
Tare
49 t
Top speed
120 km / h
I · Blueprint
Side elevation, live systems
SIDE ELEVATION · 3-UNIT ARTICULATED WELL CAR, LOADED01020304050607080910111213141516171862.1 m (203 ft 10 in) over couplers · 3 wells · 6 × 53 ft · 214 t gross6.1 mTruck centres 2.0 · 20.7 · 41.4 · 60.1 m from the A endSECTION A–A · THROUGH A WELLPlate H clearance · 6.15 mTop box — 53 ft, 2.59 m wideInter-box connector — lock sensedBottom box — 53 ft, in the wellSide sill — 690 MPa steelBearing bars — 0.33 m above rail3.01 m wide6.15 mDETAIL B · A-END TRUCK, POWER PACK, CAR NODEAxle-end generator — 300 WPower pack — 2.4 kWh LFP, 48 VCar node A — controllerCoupler — 0.87 m above railECP trainline — 230 V DC and dataLoad pin in the bolsterBrake cylinderBearing sensor — every axle endDETAIL C · ARTICULATED CONNECTORBox camera — watches the wellConnector — one truck, two unitsCentre bowl and load pinShared truck — 35.7 t axlesNo coupler slack between units
01Couplers & draft gear — ends onlyStructure
02End platforms — A and B endsStructure
03Articulated connectors — shared trucksStructure
04Wells — box rests 0.33 m above railStructure
05Side sills — 690 MPa steelStructure
06Bottom box — 53 ft in the wellFreight
07Top box — 53 ft, double-stackedFreight
08Inter-box connectors — lock sensedFreight
09Box cameras — one per wellFreight
10Load pins — every bolster, every well weighedFreight
11Axle-end generators — 2 × 300 WPower
12Power pack — 2.4 kWh LFP, 48 VPower
13ECP trainline — 230 V DC and dataPower
14Car nodes A and B — certified controllersBrakes
15Trucks × 4 — 8 axles, 965 mm wheelsBrakes
16Brake cylinders — truck-mountedBrakes
17ECP brake valve & reservoir — B endBrakes
18Bearing & wheel sensors — every axle endBrakes
II · Power & drivetrain

Power from the axle, brakes from the wire.

Each car makes its own power. An axle-end generator on each end truck charges a 48 V battery, hardest when the train brakes. The ECP trainline carries brake commands and 230 V DC from the locomotive, so every car applies its brakes at the same instant.

Truck & power pack — rotating view
An end truck: two wheelsets turning in cast side frames, the axle-end generator on the leading bearing, the brake beams and truck-mounted cylinder. On the platform above: the 2.4 kWh power pack between the two car nodes, the ECP brake valve and the reservoir.
01Wheelsets — 965 mm (38 in), 35.7 t max axle load
02Side frames & bolster — cast steel, load pin
03Axle-end generator — 300 W on the bearing end cap
04Power pack — 2.4 kWh LFP at 48 V
05Car nodes A and B — 2 × 12 W certified controllers
06ECP brake valve — electric apply and release
07Reservoir — 0.1 m³ at 6.2 bar
08Brake cylinder & beams — a shoe on every wheel
Axle-end generator
Output300 W from 40 km / h
Speed660 rpm at 120 km / h
Torque7.4 N·m at 80 km / h
Bus48 V DC through a rectifier
Drag15 N at full output
Mass14 kg
Naked system — power to brakes
Wheelsets · 965 mmAxle-end generator300 W · 660 rpm at 120 km/hRectifier & chargerto 48 V DCECP TRAINLINE · 230 V DC POWER AND DATA, CAR TO CARDC/DC 230 → 48 V10 W per car48 V DC CAR BUSBattery · 2.4 kWh LFPparked 33 days at 3 WCar nodes A & B2 × 12 W, certifiedSensorsbearings · wheels · loadsBox cameras3 × 3 WGNSS & modem3 WBrake channelSIL 3 on the nodesbrake command from the locomotiveECP brake valvepressure loop 1 kHzBRAKE PIPE · 6.2 BAR AIRReservoir0.1 m³ at 6.2 barBrake cylindertruck-mountedShoe on every wheel
III · How it is put together

Sills, wells, trucks, brakes, test.

Side sills and well frames are welded as three units and joined on articulated connectors. Trucks go under, then the brake, power and sensor kit. Each car is weighed and load-tested before service. The loop replays the build order.

I
Side sills and well frames welded
II
Units joined on articulated connectors
III
Four trucks set under the car
IV
ECP brakes, power packs, nodes and sensors
V
Weighed, load-tested, boxes loaded
IV · Specification

Design specification.

Design targets for the autonomous double-stack well car.

Length
62.1 m over couplers
Wells
3, articulated
Capacity
6 × 53 ft, double-stack
Load per well
55 t
Payload
165 t
Tare
49 t
Gross
214 t
Axle load
35.7 t max, shared trucks
Trucks
4 · 8 axles
Wheels
965 mm (38 in)
Top speed
120 km / h
Brakes
ECP on every car
Car power
2 × 300 W + 2.4 kWh
Car bus
48 V DC
Clearance
Plate H, 6.15 m
Metal content
≈ 97%
Onboard compute
Two certified nodes on every car; perception stays on the locomotive and the wayside
Modules2 car nodes — certified safety controllers, one at each end. No AI module on the car
CPU8 lockstep cores (2 × 4)
AI throughput80 TOPS total (2 × 40) — bearing, wheel, load and box models
Memory2 × 8 GB with error correction at 50 GB/s; 256 GB flash, 90-day car record
Power draw24 W compute; ≈ 45 W running with sensors, cameras and modem; 3 W parked
Process nodeMature 16 nm node, 15-year supply. Nodes are line-replaceable, swapped at mid-life
RedundancyEvery sensor is wired to both nodes. Node A is primary for the A half of the car, node B for the B half; each is hot standby for the other. Loss of both nodes or of the trainline applies the brakes.
Sensors16 bearing sensors (temperature and vibration), 8 wheel-impact sensors, 4 bolster load pins, 12 inter-box connector lock sensors, 3 box cameras on automotive Ethernet, GNSS, hand-brake switch
Safety sensorsThe brake channel reads its own: brake-cylinder and reservoir pressure transducers, 2 axle-speed sensors, derailment accelerometers at each end
LinkECP trainline to the locomotive, relayed car to car; cellular and satellite modem when parked
The car does not drive, so it carries no AI module: its nodes hear every bearing and wheel, weigh every well and check every lock. Brake commands come from the locomotive’s SIL 4 computer over the trainline and act through the car’s certified brake channel. The car agent can ask for a stop; it has no other path to the valves. The valve driver closes its pressure loop at 1 kHz. A software fault can never drive the well car outside its certified safe envelope.
Today vs IC
Structure and systems: today’s articulated well car beside the IC design
Today · 3-unit articulated 53 ft well carIC design
Size203 ft 9.75 in (62.1 m) over couplers; 3 wells, 6 × 53 ftSame envelope and Plate H: 62.1 m, 3 wells, 6 × 53 ft
Tare129,500 lb (58.7 t)49 t (108,000 lb): 690 MPa steel sills, lighter end platforms
Load per well115,500 lb (52.4 t)55 t (121,000 lb); 165 t per car
BrakesPneumatic air brakes, applied car by car down the brake pipe; ECP-capable versions rarely usedECP on every car: all cars brake at once, ≈ 1 km from 120 km/h
Power and sensingAbout 1 W for a GPS and sensor tag (GPS, hand brake, hatch, impact)48 V car power from axle generators and a 2.4 kWh battery; 2 certified nodes; every bearing, wheel, well and box sensed
SpeedSet by the track: 60 mph on Class 4, 80 mph on Class 5120 km/h
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 car is known to The Brain: each well’s weight, each box’s lock, each bearing’s temperature, updated as the train runs.
See how it works →
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Tank car →← Locomotive