How It Works

The System at a Glance

Step-by-Step: From Installation to Yield Map

1. Mount the optical sensor on your clean grain elevator The sensor unit attaches to the elevator housing using the supplied mounting brackets. It fits any combine with a standard elevator — no cutting, drilling, or modification to the machine. The sensor sits across the grain flow path, measuring how much grain is passing.

   Time: ~45 minutes

2. Fit the GPS antenna Mount the GPS antenna on the cab roof or another position with a clear view of the sky. Connect it to the sensor unit with the supplied cable. The antenna gives each yield reading its precise location.

   Time: ~15 minutes

3. Connect power Wire the sensor unit to your combine's 12V power supply using the included harness. The unit powers on automatically when the combine starts.

   Time: ~15 minutes

4. Pair the cab app Download the free Green Growth app on your phone or tablet. Open it in the cab and pair with the sensor unit over Bluetooth — takes under a minute. The app immediately shows a live dashboard: current yield rate, moisture reading, GPS speed, and a map of the current run.

   Time: <5 minutes

5. Harvest normally — no calibration runs needed Drive the combine as you normally would. The sensor records grain flow and GPS position continuously throughout the run. Because the sensor is optical rather than impact plate, you do not need to stop for load wagon calibration passes. The system stays accurate throughout the day.

   During harvest

6. Upload and generate your yield map At the end of the run, sync the harvest data from the app to the Green Growth cloud platform. The platform automatically processes the raw data: it removes header turns, speed change artefacts, and overlapping passes, then generates a clean, georeferenced yield map. Export it as a Shapefile or ISOXML file and open it in any farm management software.

   After harvest: ~5 minutes to sync and generate

What the Sensor Actually Measures

The optical sensor is mounted across the clean grain elevator — the conveyor that carries threshed grain from the combine's separation system up to the grain tank. As grain flows up the elevator, it passes through the sensor's measurement zone.

An infrared light source projects a beam across the elevator. A receiver on the opposite side measures how much of the beam is interrupted by grain passing through. More grain interrupting the beam means a higher flow rate.

This is fundamentally different from an impact plate system, which measures the force of grain striking a metal deflector. Because optical measurement is contactless, it is not affected by grain moisture, plate wear, or changes in crop conditions — which means no recalibration is required during or between harvests.

Every second, the sensor outputs: grain flow rate, GPS position (from the antenna), machine speed, and — on most models — grain moisture via an integrated moisture sensor. These inputs combine to calculate yield per hectare at each GPS coordinate.

System Specifications

• Compatible combinesAny brand, any model — all major manufacturers and older machines
• Sensor technologyOptical (infrared)
• Calibration requiredNo manual recalibration
• Installation time~2 hours, DIY
• Cab appFree — iOS and Android
• ConnectivityBluetooth (sensor to app)
• Data formatsShapefile, ISOXML
• Data ownershipFarmer — full export, no lock-in
• Supported cropsAll cereals; dedicated kit for potato harvesters

The Yield Mapping Software

Raw yield data from a combine run is noisy. Header raises, turning headlands, speed changes at field boundaries, and GPS lag all produce artefacts that make the raw map inaccurate if not filtered. The Green Growth cloud platform handles all of this automatically.

After syncing, the platform:

• Removes headland turns and header-up passes
• Filters speed change artefacts at field edges
• Corrects for GPS lag (the delay between grain entering the header and reaching the sensor)
• Interpolates the cleaned data into a continuous yield surface
• Generates productivity zones based on yield history across multiple seasons

The output is a clean, georeferenced yield map in standard GIS formats. You can use it in John Deere Operations Center, CLAAS telematics, Trimble, or any other ISOXML- or Shapefile-compatible platform.

Frequently Asked Questions