Variable Tote Shuttle
One rack, every case size. The fork faces adjust between 200 and 850 mm on approach, so a mixed or shifting SKU profile needs no mechanical reconfiguration.
SLS900 Series · Variable
One rack format, any case.
The Variable Shuttle buys flexibility with a width mechanism the Standard does not carry. Where case dimensions move around, it removes the need to zone the rack by format or to handle the awkward sizes off-system.
One rack, every case
Fork faces adjust between 200 and 850 mm on approach, so one rack format holds the full range. No zoning the building by case size, no awkward sizes handled off-system.
Improved space utilization
Reduces large goods occupying small locations and wasted space from small goods. SKU-change adaptability, no full relocation needed when SKU sizes change.
No charging downtime
Power comes from the running track, so there is no battery swap, no charging window, and no need to oversize the fleet to cover machines that are off the job.
| Movement | Bidirectional, single aisle |
|---|---|
| Payload | Rated 35 kg / max 50 kg |
| Throughput, per aisle | ≥1,000 boxes/hr |
| Continuous Runtime | Unlimited · charges on track |
| Max speed | 6 m/s |
| Position accuracy | ±3mm |
| Positioning method | DC servo + positioning photoelectric sensor + RFID |
Typical deployments
Where the SLS900 Variable excels
This model earns its keep wherever the case profile is outside your control, either because it belongs to someone else or because it changes faster than a rack can be rebuilt.
Third-party logistics
The client mix changes without notice, so the rack cannot assume a case format. One configuration serves whoever is in the building this quarter.
Apparel and seasonal
Packaging moves with the range. A rack specified around last season's cartons becomes a constraint by the next one.
Spare parts and MRO
A long tail of dimensions at low volume per line, where no single format covers enough of the catalogue to be worth optimizing for.
Growing assortments
New lines added continuously. The width range absorbs them instead of forcing a decision about what the rack was built to hold.
The complete system
The complete Variable Shuttle system
Tote shuttles handle every horizontal move inside the rack. Servo lifts carry cases between levels, and interface lines connect the rack to the rest of the building. Throughput is set by how many shuttles and lifts you run rather than by the structure, so density and speed are specified separately.
01 · Box shuttle
Travels the rack on rail, bidirectionally on the Standard, Variable and Sorting & Buffering shuttles, and across aisles on the 4-Way. Positioning to ±3 mm by DC servo, photoelectric and RFID.
02 · Layer-changing lift
Servo belt drive carrying up to 100 kg across two cargo compartments, positioning to ±2 mm, at 6 m/s unloaded.
03 · High-density racking
Multi-deep, multi-level rack from 2 to 30 m tall with aisles from 10 to 100 m long, reconfigurable as the SKU profile changes.
04 · Interface lines and charging
Chain in and out conveyors at the rack face, and a conductor rail running the length of the aisle. Shuttles collect power continuously as they travel, so they never stop to charge.
Specs
The SLS900 Variable, in full.
| Specification | Variable |
|---|---|
| Movement | Bidirectional, single aisle |
| Payload | Rated 35 kg / max 50 kg |
| Throughput, per aisle | ≥1,000 boxes/hr |
| Max speed | 6 m/s along aisle |
| Acceleration | 2 m/s² |
| Case size (L×W×H) | 200–850 × 200–850 × 60–500 mm |
| Width adjustment range | 200 to 850 mm |
| Width positioning | ±1.5 mm |
| Width adjust speed | 0.15 m/s |
| Lift fork speed, in / out | 10 / 36 m/min |
| Lift fork positioning | ±1.5 mm |
| Positioning accuracy | ±3 mm |
| Continuous runtime | Unlimited · charges on track |
| Operating temperature | −25 to 45 °C |
| Specification | Variable |
|---|---|
| Drive | Synchronous belt, electric braking |
| Travel motor | 1,000 W |
| Fork motor | 400 W |
| Width motor | 400 W |
| Positioning method | DC servo, photoelectric and RFID |
| Battery | Lithium titanate, 2.9 Ah |
| Supply voltage | DC 48 V ±10% |
| Charging style | Rail track contact line |
| Communication | 5 GHz / 2.4 GHz dual band, RS-485 |
| Structure | Q235B steel, ≥235 MPa yield |
| Certification | CE · 2006/42/EC, SGS verified |
| System availability | ≥97% to FEM 9.222 |
| Rack height range | 2 to 30 m |
| Aisle length range | 10 to 100 m |
Safety and certification
What protects people and stock.
Obstacle detection
HWA sensors stop the shuttle before contact, whether the obstruction is a load, a person or another machine.
Anti-fall and end stops
HWA sensors and mechanical end stops hold the shuttle on rail at the limits of travel.
Emergency stop
Red emergency stop on the machine, halting the shuttle immediately.
Battery protection
Over-temperature, overcharge and over-discharge protection on the onboard lithium titanate pack.
Alarm and interference
Onboard alarm function, with dual-band wireless chosen for resistance to interference across a busy rack.
Certification
CE to Machinery Directive 2006/42/EC, verified by SGS across the shuttle, the shuttle lift and the tote AS/RS system. Manufacturing certified to ISO 14001:2015.
Frequently Asked Questions
The SLS900 Variable, specifically.
How does the shuttle handle different case widths?
A servo-driven width mechanism moves the fork faces in and out between 200 and 850 mm, positioning to ±1.5 mm. The adjustment happens as the shuttle travels to the location, so it is absorbed into the cycle rather than added to it.
Does adjustable width reduce throughput?
Yes, and that is the trade being made. The Variable runs at ≥1,000 cases an hour against the Standard’s higher rate, because it carries a width mechanism and adjusts on approach. Where the case profile genuinely varies, that is still faster than running two rack formats or handling the odd sizes manually.
Can Standard and Variable shuttles run in the same aisle?
Yes. Both are the same platform on the same rail geometry under the same control software, so a fleet can mix them. Operations with a stable core range and a variable tail often do exactly that, running Standard units on the high-volume formats and Variable units on everything else.