How continuous LiDAR volume measurement changes a processHow continuous LiDAR volume measurement changes a processHow continuous LiDAR volume measurement changes a process

Most bulk-handling sites measure their stockpile weekly or monthly. A surveyor walks the pile with a total station or a drone, loads the data into a software package, generates a volume, types it into SAP. Three days later the figure is in the system. In the meantime the pile has seen another hundred truck movements.

This is not wrong. It is just a photograph.

What happens when the photograph becomes a film. A fixed OWL EYE® STOCKPILE installation scans the same pile every few minutes, day and night. Data rate is 240 000 points/s per sensor, accuracy is ±1 % after on-site calibration. What used to be a weekly data point becomes a continuous curve.

Three concrete changes show up in the field over and over — and are also discussed in Verfahrenstechnik 12/2023.

1. The control loop closes. As long as the inventory is only measured weekly, it is not a controllable process variable. Once the measurement has minute-level granularity, it can act on the input: throttle the feed conveyor when the pile crosses a defined level; bring a shift forward when a safety stock is breached. At a south-German cement plant we watched the operator start adjusting kiln-feed RPM directly off the stockpile reading after our STOCKPILE went live above a clinker store — previously it ran on a fixed setpoint.

2. Belt-scale drift becomes visible. A belt scale drifts. That is not a defect, that is physics — belt wear, temperature behaviour, material buildup on the idler. If you only inventory every few weeks, you see the drift only once it is already several percent. A continuous volume measurement in parallel with the belt gives you a plausibility setpoint: if the belt scale reports 4 % more over seven days than the LiDAR pile gain shows, it is the scale that needs attention, not the LiDAR.

3. Dispatch stops arguing with operations. Sounds banal, but it is the most common feedback in the first quarter after commissioning. When ERP, dispatch and operations all see the same number on the screen, the phone calls vanish — the ones where someone "goes to take a look at what is actually out there".

Before / after — one shift's reconciliation.

Metric	Weekly inventory	Continuous LiDAR
Measurement latency	3–7 days	5–10 minutes
Typical inventory gap	3–5 %	0.5–1 %
Labour per inventory	4–6 h	0 h (automatic)
Data availability for dispatch	weekly	live in ERP
Reaction to feed swing	shift change	minutes

What the switch does not do. A continuous measurement does not replace bookkeeping, does not replace lab analytics, does not replace the annual certified inventory for the auditor (for that we offer a separate Bulk Inventory service). What it replaces is guessing between inventory dates.

Effort vs. effect. A STOCKPILE installation on a medium-sized pile takes one to two weeks of installation work, plus half a day of calibration. From day one of production it delivers data continuously. ROI depends on material value, on inventory cost and on the frequency of dispatch arguments — most of our customers see payback inside a single fiscal year.

A photograph tells you where something was. A film tells you where it is going.

More at /stockpile/ and /volume-flow/.

Most bulk-handling sites measure their stockpile weekly or monthly. A surveyor walks the pile with a total station or a drone, loads the data into a software package, generates a volume, types it into SAP. Three days later the figure is in the system. In the meantime the pile has seen another hundred truck movements.

This is not wrong. It is just a photograph.

What happens when the photograph becomes a film. A fixed OWL EYE® STOCKPILE installation scans the same pile every few minutes, day and night. Data rate is 240 000 points/s per sensor, accuracy is ±1 % after on-site calibration. What used to be a weekly data point becomes a continuous curve.

Three concrete changes show up in the field over and over — and are also discussed in Verfahrenstechnik 12/2023.

1. The control loop closes. As long as the inventory is only measured weekly, it is not a controllable process variable. Once the measurement has minute-level granularity, it can act on the input: throttle the feed conveyor when the pile crosses a defined level; bring a shift forward when a safety stock is breached. At a south-German cement plant we watched the operator start adjusting kiln-feed RPM directly off the stockpile reading after our STOCKPILE went live above a clinker store — previously it ran on a fixed setpoint.

2. Belt-scale drift becomes visible. A belt scale drifts. That is not a defect, that is physics — belt wear, temperature behaviour, material buildup on the idler. If you only inventory every few weeks, you see the drift only once it is already several percent. A continuous volume measurement in parallel with the belt gives you a plausibility setpoint: if the belt scale reports 4 % more over seven days than the LiDAR pile gain shows, it is the scale that needs attention, not the LiDAR.

3. Dispatch stops arguing with operations. Sounds banal, but it is the most common feedback in the first quarter after commissioning. When ERP, dispatch and operations all see the same number on the screen, the phone calls vanish — the ones where someone "goes to take a look at what is actually out there".

Before / after — one shift's reconciliation.

Metric	Weekly inventory	Continuous LiDAR
Measurement latency	3–7 days	5–10 minutes
Typical inventory gap	3–5 %	0.5–1 %
Labour per inventory	4–6 h	0 h (automatic)
Data availability for dispatch	weekly	live in ERP
Reaction to feed swing	shift change	minutes

What the switch does not do. A continuous measurement does not replace bookkeeping, does not replace lab analytics, does not replace the annual certified inventory for the auditor (for that we offer a separate Bulk Inventory service). What it replaces is guessing between inventory dates.

Effort vs. effect. A STOCKPILE installation on a medium-sized pile takes one to two weeks of installation work, plus half a day of calibration. From day one of production it delivers data continuously. ROI depends on material value, on inventory cost and on the frequency of dispatch arguments — most of our customers see payback inside a single fiscal year.

A photograph tells you where something was. A film tells you where it is going.

More at /stockpile/ and /volume-flow/.

Most bulk-handling sites measure their stockpile weekly or monthly. A surveyor walks the pile with a total station or a drone, loads the data into a software package, generates a volume, types it into SAP. Three days later the figure is in the system. In the meantime the pile has seen another hundred truck movements.

This is not wrong. It is just a photograph.

What happens when the photograph becomes a film. A fixed OWL EYE® STOCKPILE installation scans the same pile every few minutes, day and night. Data rate is 240 000 points/s per sensor, accuracy is ±1 % after on-site calibration. What used to be a weekly data point becomes a continuous curve.

Three concrete changes show up in the field over and over — and are also discussed in Verfahrenstechnik 12/2023.

1. The control loop closes. As long as the inventory is only measured weekly, it is not a controllable process variable. Once the measurement has minute-level granularity, it can act on the input: throttle the feed conveyor when the pile crosses a defined level; bring a shift forward when a safety stock is breached. At a south-German cement plant we watched the operator start adjusting kiln-feed RPM directly off the stockpile reading after our STOCKPILE went live above a clinker store — previously it ran on a fixed setpoint.

2. Belt-scale drift becomes visible. A belt scale drifts. That is not a defect, that is physics — belt wear, temperature behaviour, material buildup on the idler. If you only inventory every few weeks, you see the drift only once it is already several percent. A continuous volume measurement in parallel with the belt gives you a plausibility setpoint: if the belt scale reports 4 % more over seven days than the LiDAR pile gain shows, it is the scale that needs attention, not the LiDAR.

3. Dispatch stops arguing with operations. Sounds banal, but it is the most common feedback in the first quarter after commissioning. When ERP, dispatch and operations all see the same number on the screen, the phone calls vanish — the ones where someone "goes to take a look at what is actually out there".

Before / after — one shift's reconciliation.

Metric	Weekly inventory	Continuous LiDAR
Measurement latency	3–7 days	5–10 minutes
Typical inventory gap	3–5 %	0.5–1 %
Labour per inventory	4–6 h	0 h (automatic)
Data availability for dispatch	weekly	live in ERP
Reaction to feed swing	shift change	minutes

What the switch does not do. A continuous measurement does not replace bookkeeping, does not replace lab analytics, does not replace the annual certified inventory for the auditor (for that we offer a separate Bulk Inventory service). What it replaces is guessing between inventory dates.

Effort vs. effect. A STOCKPILE installation on a medium-sized pile takes one to two weeks of installation work, plus half a day of calibration. From day one of production it delivers data continuously. ROI depends on material value, on inventory cost and on the frequency of dispatch arguments — most of our customers see payback inside a single fiscal year.

A photograph tells you where something was. A film tells you where it is going.

More at /stockpile/ and /volume-flow/.