Autonomous · Port equipment

Reach stacker

Reaches over a row and stacks five high — for depots, rail and tight corners.

Phase 5 · 2031+Concept design
Moves / hour
30
one move every 2 min
Lift, 1st row
45 t
Gross weight
≈ 75 t
Metal content
≈ 89%
I · Blueprint
Side elevation, live systems
Row 1Row 2090711Target slot, 5 highRow 2, reached over row 16.5 m wheelbase12.0 m overall length4.7 mmax lift16.3 m max lift height08010304120602131005SECTION A–A · FRONT DRIVE AXLE4.15 mTwin lift cylindersSensor headFrameOuter boom boxWear padsPLAN · SPREADER ROTATION & SIDE-SHIFT12.0 m4.15 mBoom (section B–B)DETAIL B · BOOM SECTION B–BInner (telescopic) boomExtension cylinderRotates +195° / −105°side-shift±800 mmHydraulic hosesTraction motor · 133 kW cont.Dual tyres each sideTurning radius 8.0 m · rear axle steers
01Chassis & counterweightStructure
02Battery pack, 587 kWhPower
03Outer boom & twin lift cylindersStructure
04Sensor headStructure
05Drive axle — one 133 kW traction motorDrive
06Electric hydraulic pump, 250 kWPower
07Telescopic boom & rotating spreaderHandling
08Boom pivotStructure
09Extension cylinder, inside boomHandling
10Rear steer axleDrive
11Rotator & side-shift headHandling
12Hydraulic tank & valve blockPower
13Charging inletPower
II · Power & drivetrain

Hydraulics without an engine.

An electric motor drives the hydraulic pump only when the boom moves, instead of a diesel idling all shift.

Traction motor, e-hydraulics and boom cylinders — rotating view
One 133 kW traction motor drives the front axle through a two-speed gearbox and propshaft. A separate 250 kW motor turns the hydraulic pump only while the boom moves; its two lift cylinders extend under the boom. The 587 kWh battery sits over the rear steer axle as counterweight.
01Traction motor — 133 kW continuous, 300 kW peak
02Two-speed gearbox & propshaft — to the front drive axle
03Drive axle & differential — 4 wheels, 25 km/h
04Rear steer axle — 2 wheels, 8.0 m turning radius
05Hydraulic pump motor — 250 kW, runs on demand
06Axial-piston pump — 350 bar
07Boom lift cylinders — 2, 45 t in the first row, 5 high
08Battery pack — 587 kWh, 9 hr per charge, doubles as counterweight
Drive wheel & hub reduction
Wheels6: dual front drive wheels, 2 rear steered
Drive1 traction motor, 2-speed gearbox, differential
Hub reductionPlanetary, 6:1, in each front hub
Tyre18.00-25, Ø 1.6 m, 83 rpm at 25 km/h
Regeneration75–80% of braking energy to the DC bus
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 reach stacker.

Lift, first row
45 t
Stacking
5 high, row 2 reached over row 1
Containers per lift
1 × 40 ft
Moves per hour
30 · one move every 2 min
Gross weight
≈ 75 t
Metal content
≈ 89% steel
Battery
587 kWh · 9 hr per charge
Consumption
≈ 55 kWh / hr at 30 moves / hr
Charging
350 kW, 90 min to full
Hydraulics
250 kW pump motor, axial-piston pump, 350 bar
Lift speed
21 m / min with 45 t
Traction motor
133 kW continuous, 300 kW peak
Top speed
25 km / h empty · 20 loaded
Turning radius
8.0 m
Installed power
≈ 0.6 MW
Crew
0 · no cab
Onboard compute
Two AI modules: one for the boom, one for the ground it drives over
Modules2 AI modules (boom and spreader; travel path and people) + 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; ≈ 0.3 kW with 8 cameras, 3 lidars and 2 radars — 0.6% of the stacker’s ≈ 55 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 stacker’s 15 years
RedundancyEvery sensor is wired to both modules. Module 1 is primary for the boom and spreader and hot standby for the travel path; module 2 is primary for the travel path and people and hot standby for the boom. Module 2 runs a different people-and-obstacle model, so the two never share a blind spot. Either one alone runs the stacker at reduced speed; losing both halts it with the load held.
SafetyThe SIL 3 controller has its own sensors: boom-angle and extension encoders, load cells on the spreader and lift cylinders, a chassis tilt sensor, twist-lock limit switches and safety-rated lidar and radar front and rear. It computes the tip-over envelope at 100 Hz and can stop or lower on its own. A software fault can never drive the reach stacker outside its certified safe envelope.
Sensors8 cameras on automotive Ethernet through camera aggregation switches, 3 lidars, 2 radars, boom-angle and extension encoders, load cells on the spreader, tilt sensor
LinkPrivate 5G; stack plan and box identity from The Brain; stop decided aboard in ≤ 100 ms; drive current loops closed every 1 ms
The reach stacker works in depots and rail yards among trucks and people, with 45 t on a boom that reaches 16.3 m. 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. The certified controller owns the tip-over envelope. A software fault can never drive the reach stacker outside its certified safe envelope. The Brain tells it which box to fetch and where the row will be when it gets there.
Today vs IC
Power, energy and capacity: today’s reach stackers beside the IC design
Today · 45 t reach stackerIC design
Operation1 operator per machine; no driverless reach stacker in serviceNo cab and no operator. Exceptions go to the terminal’s remote desk
PowerDiesel 265 kW, hybrid, or battery 245–587 kWh (208–470 usable) with charging to 350 kW; 3–10 h per charge587 kWh pack, 9 hr per charge, 350 kW charging; no engine
Energy≈ 12–20 L/h diesel (derived); 40–68 kWh/h electric≈ 55 kWh/hr at 30 moves (≈ 1.9 kWh per move)
Capacity45 t in row 1, 32–39 t in row 2; 5–6 high; lift height 15.1–16.3 m45 t in row 1; 5 high; lift height 16.3 m
Moves per hour≈ 15–25 (projection from 2.5–4 min cycles)30, one move every 2 min
Speed21–28 km/h unloaded; 20 km/h loaded25 km/h empty; 20 loaded
Weight71–87 t≈ 75 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 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 →