Autonomous · Port equipment

Terminal tractor

Four forty-foot boxes a trip, forty an hour: up to ten times what today's yard tractor moves.

Phase 5 · 2031+Concept design
Throughput
40 boxes / hr
up to 10× today’s tractor
Per trip
4 × 40 ft
Battery swap
3 min
Crew
0
I · Blueprint
Side elevation, live systems
05063.1 m wheelbase40 ft2 high0102040811120309101307DETAIL C · ROBOTIC TWIST-LOCKUpper boxCorner castingInter-box lockLower box castingTrailer deckDeck actuatortop: head turns 90°SECTION A–A · POD, LOOKING FORWARD2.57 mSensor domeCorner lidar/radarFrame railsDETAIL B · LIFT FIFTH WHEEL & AUTO-COUPLERrear axle406 mmTrailer gooseneckAir & power auto-connectKingpin in auto-lock jawsFifth-wheel plateLift cylindersChassis railPLAN · ROAD TRAIN, BRAKES ON EVERY AXLEConverter dollyAutonomy computeBattery slides outsideways to swapPower & data totrailer brakes & locksE-axle, dual wheels3.1 m
01360° sensor domeStructure
02Cab-less autonomy podStructure
03Swappable solid-state battery, 450 kWhPower
04Auto-coupler & drawbarStructure
05Robotic twist-locksHandling
06Road train — 4 × 40 ft per tripHandling
07Twin e-axles, 2 × 250 kW; brakes on every axleDrive
08Hydraulic lift fifth wheel, 406 mm strokeStructure
09Traction inverterPower
10Autonomy computePower
11Corner lidar & radarStructure
12Converter dollyStructure
13Trailer power & data linePower
II · Power & drivetrain

The yard's conveyor belt, on wheels.

A cab-less pod pulls a two-trailer road train with double-stacked boxes. Batteries swap in minutes, so the tractor never waits to charge.

Swappable battery and twin e-axles — rotating view
The 450 kWh pack slides out sideways from between the chassis rails for a 3-minute swap. Two coaxial e-axles, each a 250 kW motor with a reduction gear and differential on the axle, drive eight wheels; the inverter and DC bus sit above. Fifth-wheel plate at the rear, sensor dome forward.
01Battery pack — 450 kWh, 15 modules, side-swap in 3 min
02Traction inverter & DC bus — feeds both axles
03Front e-axle — 250 kW coaxial motor, 12:1 reduction, differential
04Rear e-axle — 250 kW, identical unit
05Dual wheels — 8; regenerative braking to 500 kW, friction brakes on every axle
06Fifth-wheel plate — automatic coupling, robotic twist-locks on the trailers
07Sensor dome — 360° cameras, lidar and radar
08Chassis rails — battery cradle and swap rollers
Dual wheel & e-axle
Wheels8, dual on 2 driven axles
E-axles2 × 250 kW coaxial motor, 12:1, differential
Torque1,800 N·m peak per motor; 80 kN at the tyres
TyreØ 1.05 m, 202 rpm at 40 km/h
Regeneration75–80% of braking energy to the DC bus, to 500 kW
Naked drivetrain — energy to motion
III · How it is put together

Built in blocks, joined, then brought to life.

Blocks are fabricated in parallel, joined in sequence, and the power module and autonomy core go in last. The loop below replays the build order.

POWER MODULE
I
Structural members fabricated
II
Frame erected & aligned
III
Drive & power package installed
IV
Sensors & autonomy calibrated
V
Commissioned on the terminal
IV · Specification

Concept specification.

Design specification for the autonomous terminal tractor.

Containers per trip
4 × 40 ft, two trailers, 2 high
Throughput
40 boxes / hr · 10 trips
Output vs. today
5–10× boxes per hour
Gross weight (tractor)
≈ 22 t
Combination weight
≤ 160 t, 4 loaded 40 ft
Metal content
≈ 80%
Battery
450 kWh, swappable · ≈ 7.5 hr
Swap time
3 min
Consumption
≈ 50 kWh / hr at 10 trips
Drive
2 e-axles × 250 kW, 12:1
Top speed
40 km / h
Acceleration
0.3 m/s² fully loaded, to 26 km/h
Braking
Regenerative to 500 kW; friction on every axle
Coupling
Automatic, 30 s
Twist-locks
Robotic
Crew
0 · no cab
Onboard compute
Two AI modules, because it shares the road at 40 km/h
Modules2 AI modules (path ahead; trailers and flanks) + 1 certified safety controller
CPU32 cores (2 × 16) + 4 lockstep real-time cores per module
AI throughput10,000 TOPS total (2 × 5,000, INT8 / FP4 sparse)
Memory2 × 128 GB LPDDR6, 600 GB/s per module
Power draw200 W compute; ≈ 0.4 kW with 10 cameras, 4 lidars and 6 radars — 0.7% of the tractor’s ≈ 50 kW average draw
Process node2 nm-class SoCs; safety controller on a mature 16 nm node, 15-year supply. Compute is a line-replaceable unit, swapped at mid-life of the tractor’s 12 years
RedundancyEvery sensor is wired to both modules. Module 1 is primary for the path ahead and hot standby for the trailers; module 2 is primary for the trailers and flanks and hot standby for the path ahead. Module 2 runs a different people-and-obstacle model and cross-checks module 1’s path, so the two never share a blind spot. Either one alone drives the road train at reduced speed and stops it within 17 m from 40 km/h.
SafetyThe SIL 3 / ASIL-D controller has its own sensors: wheel-speed encoders on every axle, trailer-angle sensors, limit switches on the coupler and every twist-lock, and safety-rated lidar and radar at the corners. It alone commands steering, brakes and coupling. A software fault can never drive the tractor outside its certified safe envelope.
Sensors10 cameras on automotive Ethernet through camera aggregation switches, 4 lidars, 6 radars, trailer-angle and twist-lock sensors, wheel-speed and load sensing on every axle
LinkPrivate 5G; routes, slots and crane hand-offs from The Brain, position at 10 Hz; braking decided aboard in ≤ 100 ms; drive current loops closed every 1 ms
The tractor is the fastest machine in the yard and the one that meets the most people. Both modules see every sensor; each runs its own zone and holds the other’s state warm. Commands pass from the machine agent through the certified safety channel to the drives, and no path goes around it. A software fault can never drive the tractor outside its certified safe envelope. The Brain plans each trip end to end, including the battery swap, so the tractor never waits under a crane.
Today vs IC
Boxes, power and energy: today’s yard tractors beside the IC design
Today · Terminal tractorIC design
Operation1 driver per tractor; driverless vehicles run only on fenced terminals, with 100+ cabless trucks in one port’s live trafficNo cab and no driver. Exceptions go to the terminal’s remote desk
Boxes per trip1 × 40 ft or 2 × 20 ft on one chassis4 × 40 ft on two trailers, stacked two high
Moves per hour≈ 4–8 per tractor (derived from cranes served by 5–8 tractors)40 boxes: 10 trips of 4, drop-and-hook at both ends
PowerDiesel 146–260 hp, or a 105–220 kWh battery with a 160 kW motor and 130–150 kW charging450 kWh pack swapped in 3 min; 2 × 250 kW e-axles
Energy≈ 4–8 L/h diesel or ≈ 5–8 kWh/h electric, fleet averages that include idle≈ 50 kWh/hr at full duty, ≈ 1.25 kWh per box
WeightElectric tractor 8.4–9.1 t; fifth wheel rated 36–45 t≈ 22 t tractor; ≤ 160 t combination
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 movement of this machine is planned by The Brain’s orchestration layer, mirrored in the port’s digital twin, and re-planned the moment reality drifts.
See how it works →