(All parameters based upon Agribotix’s own hardware specs)

 

General Conditions

LIGHT

• Best if overhead, bright, and uniform.

• If there is cloud cover, it must be consistent and provide uniform light filtration. 

• Cloud shadows reduce NIR reflectance and can invalidate this as a measure of crop health.

• Surveys done early on the morning or late in the day may not work for anything more than regular RGB imagery. The low sun angle will                     cast shadows from trees or relatively higher crop areas. This can invalidate NIR reflectance as a measure of crop health.

TIME OF DAY

• Too early or late in the day and the sun angle is so low that it casts shadows.

• At midday, there is the possibility of solar reflectance. This can happen with crops that have large, shiny leaves or fields that are flooded or soggy. The field becomes a mirror with an especially bright spot from the sun in each photo. In the final orthomosaic, this can create spots or stripes that are not indicative of crop health.

WEATHER

• No precipitation

• No/minimal wind

• No cloud cover is best. If there is cloud cover, it must be consistent and provide uniform light filtration.

 

Field Health, Standard

Wind speed: under 20 mph (32 kph)

Ground speed: 14 m/s

Altitude: 100 m 

Pattern: Lawnmower patter. 'Survey (Grid)' in Mission Planner.

Survey Grid Angle: if windy, perpendicular to wind direction. If no wind, oriented for least switchbacks.

Photo Interval (if not controlled by autopilot): 2 seconds

Photo Sidelap: 80%

Photo Overlap: 80% (achieved w/ camera interval of 2 seconds when traveling at 14m/s and 100m altitude)

Survey Grid Area: 20 meters beyond edge of the target survey area

 

Field Health, Dense Canopy

See this blog post for additional details.

All parameters same as Standard except…

Photo Interval (if not controlled by autopilot): increase camera interval rate to 1 second. If experiencing stitching failure, increase rate to 1/2 second.

 

Stand Cound (Beta)

See this blog post for additional details.

Wind Speed: Under 20 mph (32kph)

Ground Speed: 8 m/s

Altitude: 20m

Pattern: Lawnmower pattern. 'Survey (Grid)' in Mission Planner.

Survey Grid Angle: 

 

If flying with a gimbal:

• If light or no wind, fly perpendicular to the direction of rows (optimize count accuracy).

• If strong wind, fly perpendicular to wind direction (optimize flight efficiency).

If flying with NO gimbal:

• If no wind, fly perpendicular to the direction of rows (optimize count accuracy).

• If any wind, fly perpendicular to wind direction (maintain consistent camera angle and optimize flight efficiency).

Camera ISO: 400

Photo Interval (if not controlled by autopilot): 2 seconds

Photo Sidelap: 10%

Photo Overlap: 10%

Survey Grid Area: 10 meters in from edge of field. DO NOT include the perimeter of the field in the survey. Only survey the planted area of the field. Inclusion of the perimeter and area beyond may invalidate survey results.