Question 1

When is Radar actually a better choice than LiDAR?

Accepted Answer

Three clear cases. (1) Permanent heavy dust — cement clinker bunkers, coal silos with constant dust circulation. LiDAR's optical window blinds within hours; Radar sees through. (2) Single-point fill-level only — you don't need surface shape, just average height. Radar is simpler, cheaper to maintain. (3) Very long ranges (>300 m) — LiDAR signal-to-noise drops; Radar maintains useful return at km-scale. For everything else — clean indoor storage buildings, multi-zone piles, billing-grade accuracy, conveyor cross-sections, truck-load shapes — LiDAR's resolution wins by an order of magnitude.

Question 2

Stockpile measurement vs stockpile monitoring — what's the difference?

Accepted Answer

Stockpile measurement is a single capture event with a numeric result — volume in m³, tonnage in t, signed report. It answers the question: "How much is in this pile right now?" Manual surveys, drone flights and terrestrial laser scans are all measurements. They are point-in-time snapshots. Stockpile monitoring is a continuous stream of measurements over time, with trend, FIFO aging, dead-inventory detection and alarms. It answers: "How did this pile evolve over the shift, the week, the year — and what should we do next?" Periodic measurement is enough for audits, year-end stocktaking or due diligence. Continuous monitoring is required for operational decisions: dispatch planning, reclaim sequencing, throughput reconciliation against weighbridge tickets, alarm on overfill or unexpected reclaim. OWL EYE® STOCKPILE delivers both on the same platform: each individual scan is a fully signed measurement with ±1% accuracy, and the time-series of those scans — archived as 3D block models — is the monitoring layer. Customers run it 24/7 in live mode or on a schedule (per shift, per hour). For one-off survey-grade audits we additionally offer Bulk Inventory with a terrestrial Riegl scanner.

Question 3

Doesn't dust kill LiDAR? How do you handle dusty environments?

Accepted Answer

Dust degrades LiDAR but rarely kills it. Three layers of mitigation: (1) Multi-echo signal processing — modern industrial LiDAR returns multiple echoes per pulse and the algorithm picks the right one (the dust echo gets filtered out). (2) Optical-window cleaning — once-a-year visual inspection in normal industrial settings, every 6 months in dustier ones. (3) Compressed-air auto-cleaning — optional pulse on the window every 30 min, available on all OWL EYE® platforms for very dusty installations (cement, salt, fertilizer). In our experience: LiDAR works fine in 90 % of "dusty" industrial environments. The 10 % where it doesn't are the cases where Radar legitimately wins.

Question 4

What about ultrasonic sensors? They're cheaper.

Accepted Answer

Ultrasonic is fine for single-point fill-level in small vessels (under ~10 m, calm material, no temperature gradients). It fails on every dimension that matters for industrial bulk-material monitoring: range maxes out around 10-15 m, accuracy is ±5-10 % on uneven surfaces, dust and vapour scatter the sound waves, and there's no surface-shape information at all — just one average distance. Cost is the only LiDAR-vs-ultrasonic argument. For one small dosing hopper at €500 it's the right call. For anything stockpile-scale, the price difference is dwarfed by the inventory error you accumulate over a year.

Question 5

How does LiDAR compare to a belt scale?

Accepted Answer

Different jobs. A belt scale measures mass flow at one specific belt — accurate to 0.5-1 % when calibrated, but only at that point and only for the moving material. LiDAR measures volume in any geometry: stockpiles, bunkers, trucks, plus the cross-section of moving belts. In practice they complement each other. The belt scale is your reference for material on a single belt. LiDAR gives you stockpile inventories, bunker fill, truck-load profiles, multi-belt overview, and FIFO tracking — none of which a belt scale can do. Sachtleben uses both: LiDAR for everything stationary or geometric, belt scales as a periodic re-calibration reference for the LiDAR mass output.

Question 6

How does LiDAR compare to a drone survey for stockpiles?

Accepted Answer

Different jobs. A drone survey produces a photogrammetric point cloud from a single flight — accurate to 1–3 % with a surveyed network of ground control points and 3–5 % without, but only at that moment, only when weather and airspace cooperate, and only with a certified pilot on site. Stationary LiDAR like OWL EYE® STOCKPILE measures continuously, 24/7, in rain, dust, snow, fog and at night — no pilot, no airspace permit, no weather window. Each scan updates per-pile volume in the dashboard within minutes, so the operations team and finance work from the same live number. In practice: drones make sense for one-off as-built surveys or vast remote sites without infrastructure. For any yard where the volume number drives daily dispatch, reconciliation or contract release, continuous LiDAR is the right call. See LiDAR vs drone for stockpile monitoring for the full side-by-side.

Question 7

Why not just stick with manual surveying or drone flights?

Accepted Answer

Frequency and cost. A manual survey or drone flight gives you a snapshot — accurate (we offer it as a service ourselves), but valid only for the moment of capture. The next morning, after a shift of intake and reclaim, your inventory is wrong again. Permanent LiDAR gives you the same accuracy continuously, every 5 minutes if you want, around the clock. For a typical mid-size industrial site that runs 200+ shifts per year, the cost of permanent LiDAR amortises against ~10-20 manual surveys avoided. Plus you get FIFO tracking, alarms, and shift-by-shift reporting that periodic surveys can't deliver at any cost.

Question 8

How does LiDAR compare to a weighbridge for truck dispatch?

Accepted Answer

For dispatch, the comparison is one-sided. A weighbridge produces one mass number per truck after a 30–60 s stop-tare-ticket cycle, and tells dispatch nothing about how the truck is loaded. A LiDAR drive-through gantry produces a full 3D load shape in 8 s: volume, per-zone fill, centre of gravity and an under-/over-fill flag — all delivered while the truck is still under the gantry. In practice this means LiDAR catches problems the weighbridge cannot see at all: a truck whose volume is correct but whose density is wrong (mixed material), a tipper loaded heavily on one side, a partial fill that the contract penalises. Dispatch decides at the gantry exit, not after the truck has already left the yard. The full side-by-side data table is on the LiDAR vs weighbridge page.

Question 9

What is the throughput advantage of LiDAR vs a weighbridge?

Accepted Answer

A single weighbridge with a stop-tare-ticket cycle of 30–60 s clears ~60 trucks per hour at peak — and that is a clean theoretical peak; real operations with a queue and ticketing fall well below it. A two-lane OWL EYE® Truck Terminal gantry, drive-through at 5 km/h with an 8 s scan, sustains 200+ trucks per hour. The throughput gap matters most during shift-change peaks at quarries and recycling yards, where a queueing weighbridge becomes the bottleneck for the entire site. The LiDAR gantry removes that bottleneck without adding personnel — drive-through means the driver does not leave the cab, no operator ticket, no scale-house manning. The full throughput line is in the LiDAR vs weighbridge data table.

Dimension	Weighbridge	OWL EYE® LiDAR Truck Terminal
Measurement principle	gravimetric — load cells under steel deck	volumetric — 3D-LiDAR drive-through scan
Output	mass (kg / t)	volume (m³), mass (t) via density, full load shape
Accuracy	0.1–0.5 % mass (certified)	±1 % volume, ±2–3 % mass after density calibration
Cycle time per truck	30–60 s (stop, tare, ticket)	8 s (drive-through at 5 km/h)
Peak throughput	~60 trucks/h, one lane	200+ trucks/h, two-lane gantry
Civil works	pit, drainage, concrete slab, ramps	prepared flat surface only
Installation time	4–8 weeks incl. slab cure	5–10 working days
Wear & maintenance	load-cell drift, deck corrosion, annual recalibration	no moving parts, yearly window clean, optional air pulse
Legal-for-trade	yes — MID / OIML certified	no — operational metric, not custody transfer
Load-shape data	none	full 3D point cloud per truck
Under-/over-fill flag	indirect — only after weighing & reference	live — at gantry exit, before yard release
Multi-material handling	one density assumption per ticket	per-material density lookup automatic
Interfaces	analog, RS485, proprietary protocols	REST · OPC UA · SAP, ERP-ready
Decommissioning	pit remains, slab to remove	gantry unbolts, surface stays usable

The numbers you ask for in an RFQ. Die Zahlen, die im RFQ abgefragt werden. Liczby, o które pytacie Państwo w zapytaniu ofertowym. I numeri che chiede in una RdO. Les chiffres que vous demandez dans un appel d'offres. Los números que pide en un RFQ. Os números que você pede em um RFQ.

Throughput: 3× a weighbridge

Accuracy: ±1 % volume

Footprint: no pit

Comparison

Comparing weighbridges and LiDAR on an RFQ?