Learning Center

Levee & Contour: no contours, import errors or odd guidance

Contours won't generate, an elevation file is refused, the lightbar seems backwards, the blade doesn't move, or your coverage is gone after reopening. Also covers contours for Contour Tiling and Contour-Guided Terracing.

  • Full Automation Kit
  • Guidance Only Kit
  • Ditch Assist Lite

In the app Home › Levee

Levee & Contour builds contour lines from an elevation surface (a field survey, a point file, a GeoTIFF or LiDAR) and steers you along them with a lightbar. It's steering guidance only on every kit: the app never moves the blade in this mode. Generating and following contours needs a control module or an activated Ditch Assist Lite receiver; the DIG module and Bluetooth GPS can survey but not generate.

Before you start

  • The tablet is connected to your control module, or to an activated Reach in Ditch Assist Lite. The simulator works for practice.
  • Know which elevation source you used: a field survey, a point file, a GeoTIFF or saved LiDAR, and whether its heights are in feet or metres.

Time: 2 minutes for the quick checks. Generating contours again takes seconds.

Quick checks first

  • Connected to the control module, or to an activated Reach in Ditch Assist Lite (the simulator also works for practice).
  • The elevation source covers the whole field and is in the units you picked (feet or metres).
  • The contour interval suits the slope: smaller for flat ground, larger for steep.
Following a contour in Levee and Contour The Levee screen seen from above, travelling up the page. 1: the lightbar across the top lights on the side you have drifted to, here the right, green near the centre, then amber, then red. 2: big red arrows on the map point back to the contour, here to the left: steer toward the arrows. 3: the active contour is orange. 4: coverage paints amber behind the implement while a run is recording. 5: after you tap Stop the run turns violet and is saved with the job. 6: the other contours are one Contour Interval apart in height, 3 inches by default; grey here, coloured by height in the app. Levee and Contour is steering guidance only: you steer and you run the blade. Following a contour Steering guidance only 1 2 3 4 5 6

The lightbar lights the side you drifted to; the arrows point back to the contour. They point opposite ways on purpose. Levee & Contour is steering guidance only: you steer and you run the blade.

  1. Lightbar. Lights on the side you've drifted to, here the right: green near the centre, then amber, then red.
  2. Arrows. Point back to the contour. Steer toward them.
  3. Active contour. Orange. Tap Select Nearest, or tap a contour on the map.
  4. Coverage, recording. Paints amber behind the implement after you tap Start.
  5. Coverage, done. Turns violet when you tap Stop, and is saved with the job.
  6. Other contours. One Contour Interval apart in height (3″ by default). The app colours them by height; grey here.

Find your symptom

Tap the line that matches what you see. It opens with the causes, most likely first. Check tells you how to spot the cause. Fix tells you what to do, one step at a time.

Generate is refused“Contour guidance is for Ditch Assist owners”

You may also see You can survey a field with a Bluetooth GNSS receiver, but following contours requires a connection to your Ditch Assist control module…. The line Generating contours needs a controller or the simulator. is a reminder that always shows in the contour settings.

No control module or activated Reach connected Most likely

Check: The Wi-Fi icon at the top is grey, or you're connected to a Bluetooth GPS or the DIG module. DIG and Bluetooth can survey, but they can't generate or follow contours.

Fix:

  1. Join the control module's Wi-Fi (DitchAssist…, password 12345678) in the tablet's Wi-Fi list.
  2. In Ditch Assist, tap Home at the top of the sidebar.
  3. Tap the Levee card.
  4. If the Connect window opens, tap the green Connect button.
  5. Generate the contours again.

Ditch Assist Lite: connect your Reach with the Emlid Reach button and activate it; an unactivated Reach opens the activation window instead (how to activate).

Generate runs but draws nothing“No contours were generated from this surface. Try a different interval or surface.”
Contour Settings window: DEM size and elevation range at the top, Contour Interval with preset buttons 1, 2, 3 (selected) and 6 inches and 1 ft, a Custom inches box, a Smoothing slider set to Medium, Estimated contours: about 40 lines, and Cancel and Generate buttons.
  1. Contour Interval buttons. The row under Contour Interval: 1″, 2″, 3″, 6″ and 1 ft. Tap one, or type your own in the Custom box under them. The Smoothing slider under that smooths rough data: drag it right.

The surface is too flat or sparse for the interval Most likely

Fix:

  1. In Contour Settings, tap a smaller interval button under Contour Interval.
  2. Check Estimated contours shows more than zero lines.
  3. Tap Generate.

Still nothing? Survey again with tighter, more even passes, or import a denser file.

Wrong source units on import

Check: The contours come out far too close together or far apart.

Fix: Import the file again and tap the right Source units button (Meters or Feet) in Contour Settings. Most GeoTIFF and point files are in metres.

Generation crashed

Check: The app says Contour generation failed: …

Fix: Pick a larger interval or more smoothing and tap Generate again. If you drew a boundary, check it covers the field.

An amber warning about too many contours“Many contours — consider a larger interval.”

The interval is small for this slope

Check: Read Estimated contours in Contour Settings. The warning starts amber and Generate still works. Over 500 estimated lines it turns red and Generate stays grey.

Contour Settings for a GeoTIFF: Source units with Meters and Feet buttons (Feet picked), a red Estimated contours: about 1312 lines, the line Many contours — consider a larger interval, and a grey Generate button.
  1. Too many lines. Red over 500: Generate is grey.
  2. Source units. Here a metre file was read as feet, which also makes far too many lines.

Fix:

  1. Check Source units (GeoTIFF and point files): pick Meters for a metre file.
  2. Tap a larger interval button under Contour Interval.
  3. Tap Generate once the count is lower. With an amber warning you can go ahead, but it may be slow and cluttered.
Contours look jagged or wiggly

Rough survey data

Fix:

  1. Open Contour Settings again (generate from the same source).
  2. Drag the Smoothing slider to the right.
  3. Tap Generate.
An elevation file is refused“Could not parse GeoTIFF file” · “Too few valid points parsed (N)”

GeoTIFF problems

Check: The app says Could not parse GeoTIFF file (not a GeoTIFF), GeoTIFF has no valid elevation data (too small or empty), or This DEM is too large to load (…; limit …). Clip or downsample the DEM to the field boundary and try again.

Fix: Use an elevation GeoTIFF (.tif) that covers the field. Clip or downsample a big one to the field on a computer first. Make sure it finished copying to the tablet.

Point file problems

Check: The app says Too few valid points parsed (N), File is empty or Could not read file: ….

Fix: In the Import Point File window, check the delimiter, the header row and the Lat / Lon / Elevation column choices against the preview. It needs at least 10 good rows.

Saved survey or LiDAR problems

Check: The app says Survey has fewer than 10 points; not enough to interpolate, Could not load survey, or Could not load saved LiDAR DEM: ….

Fix: Survey more of the field, or pick another survey. For LiDAR, go online and save the field's LiDAR DEM again in LiDAR & Mapping.

LiDAR download from inside Levee failed

Check: The app says LiDAR import failed: …. The technical part often starts with "Bad state:"; that's just how the app labels the reason. "No 3DEP / HRDEM / LiDAR coverage" means no public LiDAR here. "WCS fetch failed" means no internet or a busy server.

Fix: See LiDAR & Mapping problems. With no coverage, use Survey New Field or a GeoTIFF.

The field boundary is refused“Boundary crosses itself — undo the crossing edge and try again.”

Two sides of the outline cross

Fix:

  1. Tap Undo in the sidebar until the edge that crosses is gone.
  2. Tap the corners in order around the field, so no two edges cross.
  3. Tap Done at the top of the sidebar.
The lightbar and arrows seem backwards

That's how it reads

Fix: The lights show the side you've drifted to; the big arrows point the way back. Steer toward the arrows.

To make the lightbar more or less sensitive:

  1. Tap the lightbar across the top of the Levee map. The Guidance Sensitivity window opens.
  2. Drag Lightbar full deflection: left for a more sensitive bar, right for a calmer one.
  3. Tap Save.
Guidance Sensitivity window: three sliders, Lightbar full deflection, On-track tolerance and Edge buffer (boundary inset), with Cancel and Save buttons.
  1. Lightbar full deflection. How far off you are when the bar is fully lit.
  2. Save. Keeps the change. The setting is shared with Field Survey.
The blade doesn't move by itself

Levee & Contour is steering guidance only

Fix: Steer and run the blade yourself, on every kit. Use Ditching, Simple Grading, Forming or Leveling for automatic blade control.

Orange banner while following“RTK accuracy lost — guidance may be unreliable”

The fix dropped below RTK while you follow a contour

Fix: Guidance keeps running but may be off. Slow down or stop, and wait for RTK Fixed. See RTK keeps dropping.

Coverage or contours are gone after reopening

The session was cleared Most likely

Fix:

  1. On the Levee screen, tap Load Job in the sidebar (on the start panel it reads Load Saved Job).
  2. Tap your job in the list. The contours rebuild and the coverage paints back.

Clear All only wipes what's loaded, not saved jobs. Loading a job over unsaved work asks Discard current work?: tap Cancel and save the current job first if you want to keep it.

The job file won't load or save

Check: The app says Could not load job: … or Failed to save survey to disk.

Fix: Try another job. Check free storage and the storage permission (Files won't save).

Field Survey AB line won't set“Drive farther from A before setting B (at least ~30 m for a good line).”

Too close to A, or no GPS fix

Check: Or the app says Need a GPS fix to set A. / Need a GPS fix to set B.

Fix:

  1. Wait for a GPS fix before setting either point.
  2. After Set A, keep driving straight until you're at least 30 m (100 ft) from A.
  3. Tap Set B.

Still not fixed?

Related

Did this answer your question?

Still stuck? Talk to a product specialist. 1-833-DITCH-AS · support@ditchassist.com · Monday to Friday, 8 a.m.–5 p.m. Central.

Calling about a problem? Send your app logs first so support can see what happened.