Mobile Automated Vertical Storage System for Heavy-Duty Profile Management

Floor-level handling of long steel profiles has not changed much in decades. Forklifts shuttle bundles across the yard. Overhead cranes pick from open racks. Operators walk the aisles with clipboards matching heat numbers to work orders. The process works, but it burns floor space, clock hours, and safety margin in equal measure.

Herochu’s mobile automated vertical storage system replaces that sequence with a coordinated gantry-and-rack architecture in which the storage positions themselves move independently along floor-mounted rails. Shelves shift laterally to open a shared picking aisle wherever the gantry needs access, then close back into high-density formation once the retrieval cycle completes. Every movement—shelf traverse, gantry travel, hoist lift, and load deposit—runs under PLC control through a touchscreen interface that also tracks inventory in real time.

Independent Shelf Movement: The Core Advantage

In a fixed-rack automated warehouse, the gantry does all the traveling. Every retrieval cycle requires the machine to move across the full width of the storage field to reach distant positions, then return to the picking station. Cycle times stretch with warehouse size.

Herochu takes a different approach. Each tower shelf rides on dedicated motorized trolleys embedded in the floor rail system. When the operator requests a bundle from tower position six, shelves one through five translate sideways to create an open lane directly in front of the target location. The gantry moves only the short distance into that lane, lifts the load, and returns. After retrieval, the shelves close back into their high-density parked formation.

This mobile shelf architecture delivers two practical benefits. First, average retrieval time stays short even as the storage field grows—the travel distance for any given pick is roughly the shelf opening stroke, not the full warehouse span. Second, the mechanical load on the gantry’s long-travel drive drops because it no longer runs end-to-end on every cycle. Drive components, guide rails, and chain tensioners all see lower cumulative wear, extending maintenance intervals.

Built for Steel: The Structural Foundation

The rail bed that carries Herochu’s mobile shelves is not a light-duty guide track. It is a precision-leveled steel substructure grouted into the warehouse floor, designed to hold level under the combined weight of loaded shelves and the gantry bridge. Each shelf carriage rides on hardened wheel sets with sealed bearings, driven by independent geared motors synchronized through the PLC.

The rack towers themselves follow the same heavy-duty engineering as the fixed-system counterparts. High-tensile steel grid modules start at 600 mm by 500 mm and scale up to match the pipe length and load rating. Cradles are machined or fabricated to fit the specific profile cross-section in use—round tube nests differently than rectangular hollow section, and I-beam needs side restraint that thin-wall conduit does not.

Floor space that once spread across a dozen forklift-width aisles consolidates into a single automated zone with one shared picking lane. Depending on pipe diameter and length, a Herochu mobile vertical storage system can reduce the storage footprint by 60 percent or more compared to conventional cantilever racking.

PLC Control and Operator Interface

The control architecture centers on a programmable logic controller paired with an industrial touchscreen human-machine interface (HMI). From the HMI, operators:

• Browse the digital inventory map showing every occupied position, its material grade, and the remaining quantity
• Initiate storage and retrieval cycles by selecting a SKU from the on-screen catalog
• Adjust gantry travel and hoist speeds to match material sensitivity or production urgency
• View system diagnostics, maintenance counters, and fault logs

The interface runs on a structured menu hierarchy that shop-floor personnel can learn in a single training shift. Most day-to-day operations take two or three screen touches: select the material, confirm the quantity, and press start. The gantry handles the rest.

Behind the HMI, the PLC manages the real-time coordination that makes independent shelf movement possible. When a retrieval command fires, the controller calculates which shelves need to shift, in what order, and how far, to clear a path to the target position. It sequences the moves to avoid collisions, monitors drive torque on every axis, and confirms position via encoder feedback before allowing the gantry to enter the lane.

Digital Inventory That Stays Accurate

Steel yards running manual inventory systems lose track of what is on hand for predictable reasons. A bundle gets moved to make room for a hot order and nobody logs the new location. A partial pick leaves a remnant that the next shift cannot find. Mill certifications sit in a filing cabinet while the corresponding material sits in the rack with no visible link.

Herochu binds the physical and digital worlds by making the gantry the sole agent of inventory movement. The system will not execute a putaway or a retrieval without updating the database. Every cycle writes a transaction record: timestamp, material ID, source position, destination position, operator ID, and weight confirmation from the drive torque monitoring.

The result is a live inventory view that matches physical reality because it has no other way to change. When the ERP queries the Herochu controller, it receives stock counts that reflect what is actually sitting in the racks—not what was there when the last cycle count ran three weeks ago.

Load Handling Across Profile Types

Steel profiles present a wide range of handling challenges. A bundle of 6-meter Schedule 40 pipe behaves differently under acceleration than a stack of 8-meter flat bar. Hollow sections can nest if not restrained. Round bar rolls at the slightest angle. Channel and angle want to tip.

Herochu addresses these variables at the cradle design stage. Each storage position receives a material frame engineered for the specific profile family that will occupy it:

• Round pipe and tube: V-shaped nests with side containment rails prevent rolling during gantry acceleration and deceleration
• Rectangular and square hollow sections: Flat-bottom cradles with adjustable side stops to accommodate different section widths within the same position
• Structural beams and channel: Contoured supports that cradle the flange or web, preventing twist under load
• Flat bar and plate strip: Layered compartment dividers that separate different thicknesses and prevent edge damage

The grasping mechanism on the gantry end effector mirrors this specificity. For pipe and tube, fork-style arms slide under the bundle. For flat stock, magnetic or mechanical grippers provide clean pickup without marring. Herochu’s application engineering team evaluates the material mix during the quotation stage and specs the end effector accordingly.

Safety Systems for Heavy-Duty Automation

Automated handling of multi-ton steel bundles inside a moving-shelf environment requires safety architecture that accounts for mechanical, electrical, and operational hazards. Herochu’s system layers multiple protective measures:

Physical guarding: The entire automated zone sits behind perimeter fencing with interlocked access gates. Opening any gate trips the safety circuit and brings all motion to a controlled stop. The picking station where bundles are presented for downstream handling sits outside the fence, keeping personnel separated from moving machinery during normal operation.

Area scanning: Laser safety scanners mounted on the gantry bridge and at shelf-traverse zones create detection fields that stop motion if a person or vehicle enters the work envelope. These operate independently of the gate interlocks, providing redundant protection.

Torque monitoring: Every drive axis continuously compares commanded torque against actual torque. A deviation beyond the programmed threshold—whether from a snagged bundle, a misaligned shelf, or an overload—triggers an immediate stop. The load holds in place rather than forcing through the obstruction.

Emergency stop: Redundant hardwired E-stop circuits run through safety relays rated to Category 3 per ISO 13849-1. Buttons are positioned at the operator HMI station, at access gates, and at the picking station.

Controlled deceleration: Gantry motion profiles include ramped acceleration and deceleration curves calculated for the specific load mass. The controller will not execute a move unless the load weight falls within the programmed envelope for that position.

Technical Performance Specifications

All models accept 220 V / 380 V input at 50 Hz or 60 Hz, configurable at build time.

Flexible Expansion Path

Mobile shelf systems scale in two directions: more towers along the existing rail bed, and more layers within each tower. Because the gantry rides on the same rail system that carries the shelves, extending the storage field means extending the rail and adding shelf carriages—the gantry already covers the full range through its travel axis.

Herochu configures the initial tower count and shelf layout to the customer’s current material inventory, then leaves headroom in the PLC program and the rail bed for future positions. Adding capacity later involves mechanical installation of shelf carriages, cradles, and drives, plus a configuration update to register the new positions in the controller. No control system replacement, no structural teardown.

For operations that are outgrowing their current layout—whether the constraint is floor space, picking speed, inventory accuracy, or forklift incident rate—Herochu’s mobile automated vertical storage system offers a path from manual yard handling to coordinated, touchscreen-driven material flow. The steel stays organized, the gantry does the lifting, and the operator manages inventory instead of managing traffic.