OWL EYE® Stockpile
What is stockpile monitoring? ＋
Stockpile monitoring is the continuous, automated measurement of stockpile volume and tonnage over time. Instead of a single survey on a fixed date, sensors capture the piles again and again — as often as once a minute, once per shift or on a schedule — so inventory, material age and changes are known at any moment, not only at month-end.
In LiDAR stockpile monitoring, 3D-LiDAR sensors are fixed to roofs, masts or the building structure. They scan the pile surface; the software turns every scan into a 3D block model and calculates the volume, and a stored bulk density converts it into tonnes. The data feeds dashboards, alarms and ERP/SCADA systems via REST or OPC UA. Drone flights and manual surveys, by contrast, are snapshots: useful for audits, but they do not deliver a continuous signal.
OWL EYE® STOCKPILE is a stationary LiDAR stockpile monitoring system with ±1 % volume accuracy, indoors and outdoors. For all methods side by side, see stockpile monitoring systems compared.
What is stockpile cubage (volume survey)? ＋
Stockpile cubage — known as "cubicación de acopios" across Latin American mining — is the calculation of a bulk pile's volume from its geometry to derive tonnage and inventory. Traditionally it is a periodic event: a surveyor with a total station or a drone photogrammetry flight, with results days later that are only valid for the day of measurement.
With fixed 3D-LiDAR, cubage stops being an event and becomes a continuous process: sensors above the pile capture the surface 24/7 and the system delivers volume, tonnage and a per-zone 3D model in real time — automatic volume survey at ±1 % accuracy, no drone, no surveyor, no operational stop. Details: OWL EYE® STOCKPILE; for one-off survey-grade audits see the bulk inventory service.
What is volume measurement of bulk material? ＋
Volume measurement of bulk material is the determination of the bulk volume in cubic metres and — via a calibrated material density — the mass in tonnes. It is the basis for inventory, dispatch, material-balance reporting and production control in mining, cement, sugar, wood, salt, recycling and port operations.
Four methods compete: manual survey with tape measure and theodolite (slow, inaccurate, hazardous on the pile), drone photogrammetry (1–3 % with ground control and 3–5 % without, weather- and flight-window-dependent), terrestrial laser scanning with a Riegl or Leica scanner (sub-percent accuracy, but as a one-off capture) and stationary 3D-LiDAR multi-sensor arrays (±1 % accuracy, but continuous 24/7). For live inventories and live throughput, only the stationary method is economical.
OWL EYE® implements continuous bulk-material volume measurement in four configurations — STOCKPILE for piles, VOLUME FLOW for belts, TRUCK TERMINAL for truck loading and BUNKERS & FEEDERS for silos and bunkers. A one-off high-accuracy stocktake is additionally available via the Bulk-Inventory service with a Riegl VZ-1000 (>99 % volumetric accuracy).
How do you measure bulk material in storage bays? ＋
Measuring bulk material in storage bays means capturing volume and tonnage per bay — despite push walls, partial withdrawals and uneven filling. Stationary 3D-LiDAR sensors on the shed ceiling capture every bay as its own zone: the system knows volume, fill level and material age per bay, at ±1 % accuracy — continuously, not on a survey date.
In sheds with a bay layout this is the decisive advantage over drones and manual measurement: no drone can fly safely between push walls, and walking into the bay is slow and risky. The ceiling sensors see every bay permanently from above — including per-bay thresholds (minimum stock, overfill). Details: OWL EYE® STOCKPILE — stockpile and bay monitoring.
How does LiDAR stockpile measurement work? ＋
LiDAR stockpile measurement works in five steps: - Mount: stationary 3D-LiDAR sensors are installed above the pile — on the roof, on masts or on the building structure.
- Scan: eye-safe laser pulses capture the entire surface as a dense point cloud, as often as once a minute.
- Model: the software merges all point clouds into a timestamped 3D block model.
- Calculate: the volume is computed against the surveyed base plane, at ±1 % accuracy.
- Convert: a material-calibrated bulk density turns volume into tonnage — per pile and per zone.
The decisive difference from drone flights or walking surveys: this is continuous stockpile volume monitoring, not an on-demand snapshot — every shift sees current numbers, and inventory tracking feeds automatically into your ERP or dashboard. Every step in detail: how OWL EYE® STOCKPILE measures stockpiles; all alternatives compared: 6 stockpile measurement methods.
How real-time is the Stockpile measurement? ＋
OWL EYE® STOCKPILE captures continuously. 3D-LiDAR sensors are permanently mounted overhead — on roofs, masts or building structure — and the dashboard refreshes within seconds of each scan cycle. You can run it 24/7 in live mode or on a schedule (e.g. once per shift, once per hour) depending on how often you need a fresh inventory.
Every measurement is archived as a 3D block model, so you also get the full temporal history per pile and per zone — material aging, intake, reclaim and per-shift throughput are queryable backwards in time, not just "right now".
How do you measure stockpile volume without a drone? ＋
Three ways, depending on how often you need the figure. (1) Stationary 3D LiDAR: sensors mounted once — on the roof, on lighting masts or on the building structure — scan the pile surface continuously; the software computes the stockpile volume against a surveyed base plane and converts it to tonnes via bulk density: ±1 % accuracy, indoors and outdoors, up to once per minute, no flight, no surveyor. (2) Terrestrial laser scanning as a service for a one-off audit inventory (better than 1 %, results within days). (3) Classic survey by tape, rod or total station (±2–3 % on cleanly measured piles, 5–15 % for walking surveys and profile estimates).
A drone is only a fourth option, for large open yards measured monthly; inside a hall it cannot fly at all. For a continuous stock figure the fixed system is the only method without a recurring cost per measurement — see OWL EYE® STOCKPILE and the comparison LiDAR vs. drone.
What does a drone stockpile survey cost compared with a fixed LiDAR system — and when does the fixed system pay off? ＋
A drone stockpile survey costs roughly €1,200–2,500 per flight including processing (volume per pile, orthophoto, terrain model), plus travel — and every repeat flight costs again. Accuracy with ground control points is typically 1–3 %; flights need daylight, dry weather and open-air yards, and the report arrives days later.
A fixed LiDAR system such as OWL EYE® STOCKPILE is a one-off investment: sensors are mounted once, then every scan is free — ±1 % volume accuracy, up to once per minute, indoors and outdoors, 24/7, straight into the ERP. It does not pay off by being cheaper per measurement — the inventory is usually flown one to four times a year — but by closing the gap between surveys: inventory discrepancies typically run 2–4 % against book stock, and moving from 3 % to 1 % saves €20,000–40,000 a year in our cement plant case. Rule of thumb: the number for the annual accounts → drone survey; the number for same-day decisions (reclaiming, blending, loading out, calling off a supplier) → fixed system, with live FIFO and load-out data on top. Real numbers: what stockpile monitoring costs; the flight service: drone survey; the comparison: LiDAR vs. drone.
How do you take a stockpile inventory without stopping the plant? ＋
A stockpile inventory is the count of volume and tonnage of every bulk pile on a given date — for stock balances, accounting valuation and ERP reconciliation. Done by hand, loaders and belts stop while the surveyor measures, and the figure arrives days later.
With fixed 3D LiDAR the stockpile inventory runs without stopping the plant: sensors above the yard scan the piles continuously or at scheduled times, at night and without interrupting loading and unloading, and the system delivers volume and tonnage per pile at ±1 % accuracy, 24/7, straight into the ERP. The cut-off date is no longer a shutdown — it is just one more scan. That is how OWL EYE® STOCKPILE works; for a one-off, signed survey-grade inventory see the terrestrial laser scanning service.
How do you measure bulk material with LiDAR? ＋
Measuring bulk material with 3D-LiDAR works on the time-of-flight principle: the sensor emits short laser pulses, measures the round-trip time to the material surface and assembles a dense 3D point cloud. The point cloud is projected onto a known reference geometry — building floor, bunker wall, belt cross-section — and the enclosed volume is computed directly. With a calibrated material density, tonnage falls out in the same step.
The method is deployed wherever bulk material is moved or stored: stockpiles in storage buildings and outdoor yards, conveyor belts with cross-belt scanners, bunkers and silos with top-mounted LiDAR, and drive-through truck terminals. Volumetric accuracy in a calibrated installation reaches ±1 %. LiDAR is material-agnostic — it measures salt, sand, ore, wood, cement clinker, sugar or recycling fractions equally well, because the method scans the surface optically and does not depend on conductivity or dielectric constant.
Why LiDAR rather than radar, ultrasonic or belt scales is explained at Why LiDAR; the four OWL EYE® configurations under Solutions.
Why fixed sensors instead of drones? ＋
Fixed sensors are always-on. No flight permits, no operator on standby, no weather window — the system measures during night shifts, in rain, inside storage buildings where some drones can't fly. That's why OWL EYE® STOCKPILE installs 3D-LiDAR permanently on roofs, light masts, power poles or building structure: every operational hour produces inventory data.
Point cloud data captured with a drone needs to be processed manually by a surveyor to turn into a wire mesh for volume calculations — OWL EYE® STOCKPILE performs this step automatically.
Drones still have their place for very large open-air yards or hard-to-reach geometries. We offer that too, as the Drone Survey service — but as a complement to the permanent installation, not a replacement.
What is continuous bulk-material inventory monitoring? ＋
Continuous bulk-material inventory monitoring is the real-time, ongoing capture of stockpile inventories — typically via 3D-LiDAR rather than manual surveys. Unlike an annual stocktake, which only delivers a single snapshot, a LiDAR-based system runs around the clock and updates volume, mass and tonnage every shift. The gap between weighbridge tickets, ERP bookings and physical inventory closes.
Compared to walk-arounds, drone flights or surveyor visits, the operational benefit is decisive: no downtime, no no-fly windows, no weather dependency. Instead, a timestamped 3D block model after every scan cycle — the basis for FIFO tracking, dead-inventory detection and a clean material-balance reconciliation between intake, storage and dispatch.
OWL EYE® STOCKPILE implements this principle in storage buildings and outdoor yards: fixed 3D-LiDAR sensors mounted on the roof, light masts or building structure, a single dashboard for logistics, sales and reporting. Architecture and reference customers under Stockpile monitoring; full portfolio under Solutions.
What is stockpile measurement? ＋
Stockpile measurement is the process of capturing the volume — and from it the tonnage — of a stockpile, i.e. a heap of bulk material such as ore, coal, aggregates, salt, grain or wood chips. The result is a number (cubic metres, tonnes) that feeds inventory, FIFO tracking, material balance and statutory reporting.
Four methods dominate in industry: manual tape-and-rod surveying (slow, requires shutdown, ±2-3%), drone aerial photogrammetry (fast for open yards, 1–3% with ground control and 3–5% without, weather-bound, no indoor coverage), terrestrial laser scanning (survey-grade, <1%, but periodic — one-off audits), and fixed LiDAR mounted on roofs or masts (±1%, continuous 24/7, indoor and outdoor).
OWL EYE® STOCKPILE is the fixed-LiDAR approach: permanently installed 3D-LiDAR sensors deliver real-time stockpile measurement with ±1% accuracy. Each scan is archived as a 3D block model, enabling FIFO tracking, dead-inventory elimination, inventory reconciliation against weighbridge tickets, and shift-by-shift throughput reporting. For one-off survey-grade audits we also offer the terrestrial scan as the Bulk Inventory service.
Which bulk materials does OWL EYE® STOCKPILE measure? ＋
Any solid bulk material with a defined surface — salt, potash, sugar, wood chips, pellets, biomass, coal, coke, limestone, gravel, ores, scrap, mineral concentrates, recyclate. The 3D-LiDAR captures surface geometry independent of colour or material composition; the volume-to-mass conversion is calibrated per material via a single density coefficient.
Edge cases: extremely reflective materials (clean copper sheet, polished metal piles) or fully transparent ones — for those we add a complementary sensor type to the installation.
What hardware does a LiDAR stockpile measurement system use? ＋
A fixed LiDAR stockpile measurement system uses several 3D-LiDAR sensors — for example Livox Avia or Mid-360; sensors from other manufacturers such as Hesai or Pepperl+Fuchs can be combined in the same installation. They sit in stainless-steel mounts with weather hoods (protection class IP65+, −40 to +80 °C, optional compressed-air cleaning against dust) on roofs, light masts, power poles or the building structure, and connect via WLAN, LTE, Ethernet or fibre. The sensors we supply: Livox & Hesai LiDAR sensors.
LiDAR stockpile measurement works on the Time-of-Flight principle. Each sensor emits short laser pulses and times the reflection back from the pile surface. From millions of pulses per second, the sensor reconstructs a dense 3D point cloud of the heap — distance and angle for every point.
A fixed installation uses multiple sensors mounted overhead — on the building roof, on masts, on the gantry of a stacker-reclaimer — with overlapping cones so the entire pile is covered without shadow zones. The software pipeline then turns the point cloud into a closed surface mesh, computes the volume against a stored reference floor, and applies a calibrated bulk-density value to derive tonnage. Polygons drawn in the dashboard separate volumes by bay, grade or customer.
LiDAR is contactless, runs 24/7 in any light, and works through dust thanks to multi-echo signal processing — the sensor evaluates first and last return separately, ignoring airborne dust echoes and locking onto the solid pile surface. See OWL EYE® STOCKPILE for the production system, and /why-lidar/ for the technology rationale vs radar, ultrasonic and weighbridge approaches.
How accurate is stockpile volume measurement with LiDAR? ＋
Stockpile volume measurement with stationary 3D-LiDAR sensors reaches a volumetric accuracy of ±1 % in a calibrated installation. The figure is from production operations — K+S (salt piles in open storage), Nordzucker (sugar-syrup piles and beet bunkers), proFagus (wood piles in outdoor yards), Aurubis (concentrate piles) and Sachtleben Minerals — and not a laboratory claim. Residual uncertainty stems mostly from material density, not from the geometric capture: LiDAR measures volume directly; converting to tonnage depends on moisture, grain size and storage compaction.
Method comparison: drone photogrammetry delivers 1–3 % on volume with a surveyed ground-control network and 3–5 % without, depending on flight altitude, lighting and GCP layout. A terrestrial laser scan with a survey-grade Riegl VZ-1000 achieves <1 % as a single capture, but is not a continuous mode. Stationary multi-LiDAR systems sit at ±1 % and deliver the decisive advantage: every shift, every hour, no downtime, no pilot, no walk-around.
OWL EYE® STOCKPILE installs the sensors on the roof, light masts or building structure as a turnkey solution; calibration is a one-off on-site step against a reference scan. Sensor architecture, references and integration under Stockpile volume measurement.
Which factors influence stockpile measurement accuracy? ＋
Fixed multi-sensor LiDAR delivers ±1% volumetric accuracy for stockpile measurement under industrial conditions, measured at active sites — not a lab figure. The number is reproducible across cement clinker domes, salt warehouses, ore piles, sugar silos and wood-chip yards.
Three factors set the achievable accuracy: material-density calibration (the conversion from m³ to tonnes is only as good as the density model — we calibrate per material and per moisture band), sensor coverage and overlap (enough sensors with overlapping cones to eliminate shadow zones on the pile), and dust mitigation (multi-echo processing plus, where needed, software dust filters tuned per site). Get those three right and ±1% holds 24/7.
In context: terrestrial survey-grade scanners reach >99% accuracy (<1% error) — better, but only for periodic one-off audits because they require an on-site operator. Drone photogrammetry lands at 1–3% with a surveyed ground-control network and 3–5% without and is weather-bound. Fixed LiDAR at ±1% continuous is the operational sweet spot. Reference deployments: K+S (salt), Nordzucker (sugar), proFagus (wood charcoal), Aurubis (copper concentrate), Sachtleben Minerals (barite). See /stockpile/ for the system and /why-lidar/ for the technology comparison.
How many sensors does my storage building need? ＋
It depends on pile geometry, bin layout and material shape. Concrete reference points from typical installations:
- Storage bin 10 × 20 m: usually one sensor — and often a single sensor covers two adjacent bins.
- Long storage bin 12 × 50 m: two sensors per bin. When multiple such bins sit side-by-side, two sensors typically cover two bins together.
- Large storage building 100 × 100 m with multiple zones or piles: at least 6-12 sensors, depending on pile shapes, internal supports and sight lines.
Higher mounting positions cover more area per sensor. We calculate the optimal layout during the on-site survey before any quote, including blind-spot analysis — you only pay for the sensors you actually need.
How does OWL EYE® monitor ore stockpiles at steel and mining sites? ＋
Ore yards — iron ore, copper, bauxite, manganese, nickel concentrates — are continuous-flow environments where stacker, reclaimer and conveyor traffic never stops. Sending in a survey crew is unsafe, drone overflights only give a snapshot, and bunker-style level sensors miss the blending geometry.
OWL EYE® delivers ore stockpile monitoring via permanently mounted 3D-LiDAR sensors on mast clusters or building structure. The point clouds fuse into one block model that is stacker- and reclaimer-aware: blending-bed ratios, per-zone inventory and FIFO aging are tracked automatically with ±1% volume accuracy. The dashboard plugs into burden-control, MES and ERP via REST, OPC UA and SAP — turning the ore yard from an estimate into a live tonnage figure.
How does OWL EYE® monitor aggregate stockpiles and material bays? ＋
Aggregate yards — sand, gravel, crushed rock, recycled aggregates, C&D fines — typically split into sectioned bays of differing grain size and grade. Manual surveys lag the daily turnover, weighbridge tickets only capture intake, and per-bay reconciliation is normally done by eye.
OWL EYE® STOCKPILE delivers continuous aggregate stockpile monitoring from overhead 3D-LiDAR. A single sensor cluster covers multiple bays; polygons drawn in the dashboard separate volumes by bay, by grade, by customer reservation. Each scan updates per-bay inventory, intake/reclaim curves and aging — so dispatch, sales and statutory reporting work from the same live number. Throughput on transfer belts is captured by OWL EYE® VOLUME FLOW on the same platform.
How does OWL EYE® monitor waste and scrap stockpiles? ＋
Waste and scrap yards are the hardest case: heterogeneous material, rapidly changing geometry, varying bulk density, dust, and a regulatory obligation to report what actually sits on site. Weighbridge data alone hides waste inventory between intake and dispatch, and the bulk density a weight calculation depends on is essentially an estimate.
OWL EYE® STOCKPILE delivers waste stockpile monitoring by capturing volume directly with permanently installed 3D-LiDAR — ±1% accuracy on the pile geometry itself, no density assumption required. Indoor scrap storage buildings, outdoor metal yards, RDF/SRF bunkers and C&D streams are all covered by the same platform. Aging zones flag long-standing waste inventory before it becomes a compliance or fire-load problem; per-zone volume reconciles offtake contracts and statutory reports.
How does OWL EYE® monitor clinker and concentrate stockpiles? ＋
Clinker stores and mineral-concentrate stockpiles share a tough profile: high-value material, abrasive dust, FIFO ageing that matters for quality, and downstream mills that expect a steady blend. Manual gauging is slow and unsafe; bin-level radars miss the per-zone geometry needed for blending.
OWL EYE® STOCKPILE delivers concentrate stockpile monitoring via overhead 3D-LiDAR mounted on building structure or mast clusters — continuous coverage of clinker domes, concentrate buildings and longitudinal blending beds, ±1% volume accuracy through dust. Per-zone concentrate inventory, blending-bed ratios and stacker/reclaimer position feed mill-feed control and homogenisation logic. Every measurement is archived as a timestamped 3D block model, so material aging is queryable backwards in time.
What does real-time measurement actually mean in OWL EYE®? ＋
In OWL EYE® real-time measurement means the sensor, the edge processing unit and the dashboard refresh in a continuous loop — typically within seconds of a fresh scan, not minutes or shifts. Every variant runs the same loop:
- Volume Flow — cross-section line scans integrated over belt speed, updated several times per second for live volume / mass flow.
- Stockpile — overhead 3D-LiDAR cycles a full scan per minute or per shift (configurable), so the dashboard reflects each intake, reclaim or reshape within seconds of completion.
- Truck Terminal — ~8 s drive-through scan, payload published before the truck reaches the exit.
- Bunkers & Feeders — continuous fill-level sampling at sub-second cadence.
"Real time" in this context is the time from physical change to value-in-the-control-room, not just a display refresh. Throughput, fill level and threshold alarms reach your SCADA, SAP or Power BI in the same scan cycle — so an operator reacts to what is happening, not what happened an hour ago.
How does OWL EYE® integrate with SAP, OPC UA and Power BI? ＋
OWL EYE® ships with the same integration toolkit across every variant — Volume Flow, Stockpile, Truck Terminal, Bunkers & Feeders and Mobile Mapping. SAP integration uses native SAP ABAP connectors that book volume or mass events straight into the production module (MM, PP, QM), so tonnages, stock movements and material flows stay in sync with no middleware in between.
For real-time process control we expose a documented OPC UA server and a REST API. Volume, mass flow, fill level and threshold alarms reach DCS, SCADA, PLC or MES within seconds of every scan. For legacy automation we add Modbus TCP and 4–20 mA on the same edge unit.
For analytics, Power BI integration reads the same measurement dataset via REST or a SQL view — one real-time measurement source of truth across operations, ERP and BI. Every interface is documented and ships as part of the standard package; container-based deployment lets your IT team run OWL EYE® on premise, in the DMZ or in a private cloud.
How does OWL EYE® STOCKPILE cope with clinker dust in a cement plant? ＋
Clinker silos and pre-blending buildings are among the dustiest environments on site — fine particulate plus residual heat from the cooler exhaust will fog any optical sensor that is not built for it. The OWL EYE® BUNKER / STOCKPILE heads we deploy in cement plants are IP65-rated stainless-steel housings with an optical window that is purged on a schedule by a compressed-air pulse (typically every 30 minutes inside a clinker building).
The 3D-LiDAR itself sees through airborne dust by averaging multiple returns per voxel — accuracy stays inside +/- 1 % of the bulk volume even during reclaim. For aggressive chloride atmospheres around the cooler we ship a corrosion-resistant variant. The system runs 24/7 without operator attendance.
How does OWL EYE® integrate with a cement mill control system? ＋
Each OWL EYE® head exposes its volume, tonnage and zone-aged inventory as OPC UA tags and as REST endpoints. In a cement plant the typical wiring is: 3D-LiDAR → on-site edge server → mill PLC (Siemens PCS 7, ABB 800xA or Rockwell) via OPC UA, plus a parallel feed to the plant historian (PI, Aspen IP.21).
For the kiln feed and the cement mill the system delivers a live silo level per minute so the operator can balance pre-blending, raw mill and finish-mill draw without manual dips. ERP-side (SAP S/4HANA, IFS) we push end-of-shift tonnage as an iDoc or REST call against the material-document API.
See silo overfill protection for the safety-rated variant.
What is the typical ROI for OWL EYE® in a cement plant? ＋
For an integrated cement works moving 1.5–3 Mt of clinker per year, the three biggest savings stack roughly as follows:
- Dead inventory: reclaim-side LiDAR typically uncovers 3–6 % of pile volume that was unreachable or aged out — at €25–€35 per tonne of cement that recoverable stock is worth €150k–€400k once.
- FIFO + quality: age-tracked zones cut out-of-spec clinker blending by 1–2 %, avoiding off-grade campaigns.
- Weighbridge avoidance: internal transfers to the cement mill stop touching the legal-for-trade scale, freeing 30–60 minutes per shift.
Hardware payback in a typical cement-plant configuration is 9–18 months.
Can OWL EYE® measure stockpiles near a blast furnace or EAF? ＋
Yes — and it is one of the use cases we ship the most ruggedised housing for. Sinter feed, coke yards, lump-ore bins and EAF scrap bays all sit close to radiant heat from the furnace plus airborne iron-oxide dust. The standard IP65 stainless head tolerates ambient up to about 60 °C; for line-of-sight to glowing slag or near the tap-hole we add an active-cooled sleeve and a heat-shielded window.
The 3D-LiDAR sees through coke and ore dust because we work at infrared wavelengths well above the visible-light scattering peak, and we average multiple returns per voxel. Volume accuracy stays inside +/- 1 % on a coke stockpile during full reclaim. The sensor runs 24/7 without operator intervention.
How does OWL EYE® feed data into the blast-furnace Level 2 system? ＋
In a steelworks the Level 2 process-automation layer (typically Primetals, SMS digital or in-house) wants a clean, timestamped tonnage signal per material per minute — sinter, coke, lump ore, additions. OWL EYE® delivers it via OPC UA straight into the L2 burden-distribution model, plus a parallel feed to the historian (PI, IBA-PDA) for long-term metallurgical analysis.
For the BOF and EAF scrap yard the integration is wider: 3D-LiDAR → edge server → mill MES (PSI Metals, QuMES) over REST, so charge-mix optimisation works with measured rather than nominal scrap volumes. ERP buyback (SAP S/4HANA) closes the loop on raw-material reconciliation. The signal is continuous, in real time — no manual dip, no truck count, no monthly survey.
What ROI does OWL EYE® deliver in a steelworks? ＋
Steel mills usually justify the system on three lines:
- Coke and ore dead inventory: typical reclaim-side discovery is 4–8 % of the pile that surveys had double-counted or that aged out behind the reclaim front. On a 200 kt coke yard at €280–€350 per tonne that is a one-off recovery of €2–€5 m on the books.
- L2 burden accuracy: a tighter sinter-to-coke ratio cuts coke rate by 2–4 kg/tHM — at a 3 Mt/a furnace that pays the sensor cluster in well under one year.
- Weighbridge avoidance: internal transfers between yard and stockhouse stop queuing at the legal-for-trade scale.
See weighbridge alternative for the full TCO model.
Can OWL EYE® measure heterogeneous recycling material with mixed densities? ＋
Yes — recyclate, scrap and mixed waste are typical OWL EYE® STOCKPILE targets. The 3D-LiDAR measures surface geometry, so the volume signal is independent of what is in the pile: shredded metal, mixed plastics, paper bales, RDF, glass cullet, e-waste fragments — all just surfaces above a known floor.
The mass conversion is the part that is sensitive to material mix. We solve it in two ways: per zone-polygon density coefficient (one number per product), or — for very mixed feed — a rolling density calibration tied to the weighbridge feedback every 50 trucks. Operators see volume in real time, while tonnage smooths to within +/- 2 % on truly heterogeneous piles. The IR signal sees through airborne paper and plastic dust without issue.
How does OWL EYE® integrate with a recycling-plant SCADA? ＋
Sorting plants and material-recovery facilities typically run a SCADA on top of a Siemens S7-1500 or Beckhoff PLC backbone, with a Wonderware / AVEVA or Ignition HMI. OWL EYE® hooks in three ways at once:
- OPC UA tags for live volume, tonnage and per-zone age — consumed by the SCADA for hopper levels, bunker fill alarms and feed-rate balancing into the shredder or optical sorter.
- REST / MQTT for the MES (e.g. AMCS, RecyClass) — closing the loop on input vs output reconciliation per shift.
- ERP iDoc / REST against SAP S/4HANA or the recycling-specific ERP (Enwis, RSAG) for end-of-day tonnage and value-locked inventory reports.
See silo overfill protection for the safety-rated bunker variant.
What is the ROI of OWL EYE® in a recycling plant? ＋
Recycling sites typically book three savings:
- Dead inventory recovery: on a mixed-recyclate yard we routinely surface 5–10 % of pile volume that the previous manual survey had missed — at €40–€180 per tonne for sorted output that is a one-off €100k–€600k.
- Weighbridge avoidance for internal moves: wheel-loader transfers between input bay and shredder feed stop touching the legal-for-trade scale, freeing 20–40 minutes per shift and removing a constant bottleneck.
- Quality bonus on output: zoned age tracking enables strict FIFO on hard-to-store fractions (RDF, paper) and avoids quality downgrades.
Hardware payback in a mid-sized MRF lands at 10–18 months.
How does OWL EYE® handle salt caking and corrosive halide atmospheres? ＋
Salt storage buildings have two stubborn problems for any sensor: chloride-rich air corrodes ordinary stainless steel, and surface caking changes the bulk density over time. The OWL EYE® heads we ship to salt mines and de-icing depots use the corrosion-resistant housing variant — coated aluminium or hardened stainless with a sealed optical window, IP65 and a built-in heater plus dew-point control to suppress condensation that would otherwise drive chloride pitting.
Caking does not fool the geometry measurement (the surface is still measured at +/- 1 %), but it shifts mass per cubic metre. The dashboard supports a per-zone density coefficient that operators can re-calibrate per storage building and per season. Sensors run 24/7 and need a 6-monthly sight check plus a yearly window clean.
How does OWL EYE® connect to a salt-yard ERP and dispatch system? ＋
De-icing salt and industrial-salt operations are dispatch-driven — peak winter mornings move thousands of tonnes against political contracts. OWL EYE® STOCKPILE plugs into that stack at two levels:
- ERP: SAP S/4HANA, Microsoft Dynamics 365 or the yard-specific ERP (e.g. K+S internal, Compass dispatch) — REST or iDoc push of total stock, per-zone tonnage and value-locked monthly close.
- Dispatch / TMS: live volume per storage building feeds the truck-loading planner so the dispatcher can pre-commit tonnage without a manual walk in the dark.
Inside the storage building, the system also runs as a weighbridge alternative for internal moves — keeping the legal-for-trade scale free for outbound trucks under contract.
What ROI does OWL EYE® deliver in a salt operation? ＋
Salt mines and de-icing-salt depots typically book three lines:
- Dead inventory recovery: on a 100–250 kt road-salt hall we routinely surface 4–7 % of pile volume that manual surveys had double-counted between zones — at €60–€90 per tonne that is a one-off recovery of €240k–€1.5 m on the books.
- Peak-day weighbridge avoidance: internal hall transfers stop queuing at the legal-for-trade scale, which is what bottlenecks the dispatch window on a snow morning.
- Caking + FIFO: age-tracked zones cut the share of caked surface stock the loader has to break up.
Payback for a depot-scale install lands at 8–14 months.
Does grain moisture affect OWL EYE® STOCKPILE accuracy? ＋
The 3D-LiDAR measures the surface geometry of the grain pile, and that signal is unaffected by moisture content — wheat at 12 % and wheat at 16 % look identical to the sensor. Volume accuracy stays inside +/- 1 % regardless.
Moisture affects the volume-to-mass conversion, because bulk density of grain changes by roughly 0.7–1.2 % per percentage point of moisture above the storage baseline. The dashboard handles this with a per-zone density coefficient that operators set per intake batch, or that we automate by reading the moisture probe at the elevator bucket and adjusting in real time. Net mass accuracy on a managed grain elevator typically lands inside +/- 1.5 %, which is well below normal weighbridge campaign variance.
How does OWL EYE® hook into a grain-elevator PLC and silo management system? ＋
Grain elevators usually run a Siemens S7 or Allen-Bradley PLC on the conveying lines plus a silo management system (e.g. Cimbria SMS, AgriLogic, Bühler MERCATOR) on top. OWL EYE® speaks the relevant protocols natively:
- OPC UA for live silo and flat-store volume — consumed by the PLC for overfill protection and conveyor routing.
- REST / Modbus TCP for the silo management system — per-bin tonnage, per-zone age, intake vs reclaim balance.
- ERP push (SAP S/4HANA, Microsoft Dynamics, or grain-specific ERPs like Cultura, NextFarm) for monthly closing and customer-account inventory.
Combined with a silo overfill protection licence, the loop is closed both for accounting and for safety.
What ROI does OWL EYE® deliver in a grain elevator? ＋
Grain elevators and feed mills typically book three savings:
- FIFO + spoilage: on a 50–100 kt flat store the age-tracked zones cut the share of grain that crosses the spoilage threshold by 0.5–1.5 % — at €200–€280 per tonne that is €100k–€400k per year in recovered first-quality output.
- Dead corners: reclaim-side LiDAR surfaces 2–4 % of pile volume that the loader had stopped reaching — booked once into closing stock.
- Weighbridge avoidance: internal transfers between flat store and silo stop touching the legal-for-trade scale.
Add the reduction in monthly manual surveys (no climbing, no laser tape, no spreadsheet) and payback in a mid-sized elevator lands at 10–16 months.
Can OWL EYE® handle the bulk-density variation of wood chips and biomass? ＋
Yes — and this is where stationary 3D-LiDAR clearly beats truck-counting or belt-scale-only operation. Wood chips, hog fuel, bark and pellet feedstock vary in bulk density between 250 and 450 kg/m³ depending on moisture, species mix and compaction. The 3D-LiDAR measures the surface geometry, so the volume signal stays accurate to +/- 1 % regardless of what the density is.
The volume-to-mass conversion is handled per zone: operators set a density per product (debarked spruce, mixed hardwood, pellets) and per intake batch. For boiler-feed sites the system can read the moisture analyser at the belt and adjust the density in real time. End result: the boiler controller sees a clean continuous tonnage signal instead of a step function from the weighbridge ticket.
How does OWL EYE® integrate with a sawmill or biomass-plant control system? ＋
Sawmills and pellet plants typically run a Siemens, Beckhoff or Allen-Bradley PLC on the line, with a mill MES (e.g. MiCROTEC, USNR, LIGNUM) and an ERP (SAP S/4HANA, Microsoft Dynamics, branche-specific T-Wood / Profitree) on top. Biomass CHPs sit on a DCS like Siemens PCS 7 or ABB 800xA.
OWL EYE® delivers volume, tonnage and per-zone age via:
- OPC UA to the PLC / DCS for live boiler feed or sawmill log-yard balancing.
- REST / MQTT to the MES for per-product inventory and end-of-shift reconciliation.
- ERP push for monthly closing and customer-account reporting.
See silo overfill protection for the safety-rated pellet-silo variant.
What is the payback for OWL EYE® at a sawmill or biomass plant? ＋
Wood and biomass yards typically book three savings:
- Dead inventory + density truth: a 30–80 kt wood-chip yard regularly reveals 5–9 % of pile volume that manual surveys had missed or that bulk-density assumptions had over/under-counted — at €40–€70 per tonne of dry chip that is €60k–€500k one-off.
- Boiler feed stability: a continuous tonnage signal cuts boiler MW deviation by 1–3 %, reducing unplanned trips and fossil co-firing.
- Weighbridge avoidance: internal moves between hog-fuel pad and silo stop touching the legal-for-trade scale.
In a typical biomass CHP setup, hardware payback lands at 10–18 months.
Is OWL EYE® safe in sugar silos with dust-explosion risk? ＋
Sugar dust is an explosive atmosphere (ATEX dust zones 20/21/22), and any sensor going into a sugar silo or a refined-sugar warehouse must carry the corresponding certification. OWL EYE® ships in an ATEX-rated variant for dust zones 20, 21 and 22, with the matching gas-zone option where solvents are present.
The optical window is sealed at IP65, the housing is corrosion-resistant for sugar's hygroscopic chloride content, and a scheduled compressed-air pulse keeps the window clear. There are no moving parts inside the silo and no ignition source. Power and data leave the zone through certified barriers. The full ATEX detail is on the silo overfill protection page; that variant is also functional-safety rated for use in the overfill safety chain.
How does OWL EYE® plug into a sugar-refinery MES and ERP? ＋
Sugar refineries and beet-sugar factories run a Siemens PCS 7 or ABB 800xA DCS on the process side, a MES (e.g. PARSEC TrakSYS, AVEVA MES, Bühler MES) above it, and SAP S/4HANA on the ERP layer. OWL EYE® STOCKPILE and OWL EYE® BUNKER deliver continuous volume and tonnage data into all three:
- OPC UA for live raw-sugar, refined-sugar and molasses silo levels — consumed by the DCS for overfill protection and crystalliser feed balancing.
- REST to the MES for shift reconciliation and FIFO management of refined-sugar warehouses.
- iDoc to SAP S/4HANA for material-document booking and monthly closing.
Combined with the ATEX-rated silo overfill protection licence, the same hardware also covers the safety chain.
What ROI does OWL EYE® deliver in a sugar refinery? ＋
Sugar producers typically justify OWL EYE® on three lines:
- Refined-sugar FIFO: warehoused white sugar that ages out of bonus quality is the single biggest avoidable loss in the back end of a refinery. Age-tracked zone polygons cut quality downgrades by 0.5–1.5 % — at €450–€600 per tonne of premium output that is €200k–€900k per year on a medium refinery.
- Raw-sugar dead inventory: reclaim-side LiDAR routinely uncovers 3–6 % of pile volume the manual survey had missed.
- ATEX safety chain: replacing mechanical overfill switches with a measured continuous level removes a recurring inspection cost.
Hardware payback in a mid-sized refinery lands at 8–14 months.
What is a stockpile survey system (Haldenvermessungssystem)? ＋
A stockpile survey system — in German industry usage a Haldenvermessungssystem — is a permanently installed measurement setup that captures the volume and tonnage of bulk-material stockpiles automatically, without a surveyor walking the pile or a drone being flown. The core components are 3D sensors (LiDAR, in some products radar or cameras) mounted above the storage area, a processing unit that turns the point clouds into volumes, and a software layer that pushes the numbers into dashboards and ERP systems.
The decisive difference to survey services is continuity: a service delivers one number per visit; a system delivers a number every scan cycle — hourly, per shift, or live. That turns stockpile surveying from an annual audit exercise into an operational data feed for FIFO, load-out planning and material balance.
OWL EYE® STOCKPILE is such a system: fixed 3D-LiDAR sensors, ±1% volume accuracy, every scan archived as a 3D block model, delivered turn-key including mounting, calibration and SAP/OPC UA integration.
How does contactless stockpile surveying work in real time? ＋
Contactless stockpile surveying means no person and no device touches the pile: 3D-LiDAR sensors mounted on the roof, on light masts or on the building structure sweep the material surface with eye-safe laser pulses. Each sweep produces a point cloud of the entire pile geometry; overlapping sensor cones eliminate shadowed zones.
The real-time part happens in software: every scan cycle is converted into volume (m³) and — via material-specific bulk density — into tonnage, then written to the dashboard and to interfaces such as REST, OPC UA or SAP within seconds. No downtime, no closed-off areas, no weather window: the measurement runs during normal loader and conveyor operation, indoors and outdoors, day and night.
In production this means the difference between "last surveyed in March" and "current as of 14:03". OWL EYE® STOCKPILE delivers this contactless, real-time surveying at ±1% volume accuracy — proven at K+S, Nordzucker and proFagus, among others.
Stockpile surveying by drone vs. stationary LiDAR — what's the difference? ＋
Both produce a 3D model of the pile — the difference is frequency, coverage and recurring cost.
A drone survey is a service: a pilot flies the yard, photogrammetry or airborne LiDAR turns the images into a model, and days later you receive a report. Accuracy with good ground control is 1–3%. It works well for large open yards measured monthly or quarterly — but it is weather- and daylight-bound, cannot fly inside buildings, and every additional flight costs again.
A stationary LiDAR system is infrastructure: sensors are mounted once, then every scan is free. Volumes update continuously at ±1%, indoors and outdoors, and feed the ERP automatically. Cost per measurement is the wrong yardstick, though: the inventory is typically flown one to four times a year, and what a fixed system pays for is the time between surveys, when inventory discrepancies of 2–4% against book stock go unseen. Rule of thumb: if you need the number for the annual accounts, a drone survey does the job; if you need it for same-day decisions — reclaiming, blending, loading out, calling off a supplier — a fixed system does, with live FIFO and load-out data on top that no periodic survey can provide.
Our own portfolio covers both sides honestly: drone survey as a service for periodic needs, OWL EYE® STOCKPILE for continuous surveying. Which fits your case is a 15-minute conversation, not a leap of faith — see also the full LiDAR vs. drone comparison.