Check the weather and field conditions of the area you intend to fly.
- Ideal conditions for data collection are sunny or overcast skies (uniform lighting conditions), within a few hours of solar noon.
- SLANTRANGE sensors are not designed to be waterproof; do not fly in the rain!
- Sensor orientation is at the mercy of aircraft orientation (assuming no gimbal is being used): in gusting conditions, fly with more overlap (25-40%) to ensure complete coverage in the midst of more variation in aircraft attitude (pitch, roll, yaw).
- If it is too dark to see your shadow, it is likely too dark to collect high quality data. At the highest level, the sensor is measuring the interaction of plants with sunlight; less sunlight means a higher signal to noise ratio and thus lower quality data. Additionally, darker conditions result in longer sensor exposure times, and thus higher potential for image blur. If flying in overcast or darker conditions, decrease flight speed to compensate, especially if flying at low altitude or collecting population data.
Program your mission using mission planning software. DO NOT fly missions by hand.
Refer to the user guide section Mission Planning and the DroneDeploy app's SLANTRANGE Flight Calculator to determine flight altitude and velocity settings that will generate data products tailored to your crops in their current growth stage. For example, if flying a corn field in a population stage with plants that are 5 inches x 2 inches the recommended flight plan looks like:
The sensor must fly forward throughout the data collection ("lawnmower" pattern). Make sure the aircraft is programmed to turn 180 degrees at the end of each flight leg in a "lawnmower pattern". Do not fly forward on one pass, crab to one side, then fly backward on the next pass.
- The standard 8 degree mount of the sensor is not optimized for flight speeds above 12 m/s. If flying faster than 12 m/s, increase the angle of the sensor mount as needed (also taking into consideration the wind conditions, other payloads on the aircraft, etc...) to keep the sensor parallel to the ground in forward flight.
- Plan flight legs to extend slightly beyond the edges of the field you are mapping so your aircraft has time to reorient to the new heading, accelerate to its prescribed speed, and level off for a straight and stable flight leg before flying over the area of interest. (The pitch and roll of the aircraft can make the images taken during the turns unusable for map generation.)
Three variables to optimize if possible, in order of importance:
- In the presence of a crosswind, fly perpendicular to the wind to maintain a consistent aircraft roll angle. Flying parallel to the wind can cause large differences in aircraft pitch or ground speed on legs flying directly into and away from the wind. If the aircraft is noticeably affected by the wind, plan your flight to compensate and do not worry about recommendations 2 and 3.
- Plan your flights with legs across the long dimension of the field. Flying across the narrow dimension of a field in short passes results in more turns, longer flight time, and thus lower area coverage.
- If imaging row crops with significant bare soil content visible between rows, fly parallel to the crop rows.
- Make sure your aircraft is programmed to fly above power lines, trees, or other obstacles at the edges of the field!
Ensure proper sensor mounting and hardware setup according to Mounting sections for the 2p/2i and 3p sensors.
- The pitch of a multirotor aircraft in forward flight is a function of air speed. The sensor should be mounted at an angle to compensate for forward pitch. Significant increases or decreases in flight speed may affect the pitch angle of the aircraft. If you fly missions at a significantly different airspeeds, adjust the mount for the different flight plans to keep the sensor oriented as close to nadir as possible.
- Use the microfiber cloth to clean any dirt from the sensor window. It is advantageous to take off and land on some sort of landing pad: i.e. a heavy canvas, plastic sheet, plywood, or otherwise to prevent dirt from blowing up onto the sensor window
- Ensure the Field and AIS sensors are mounted in accordance with the Mounting section of this guide, and connected via the AIS cable, and all wires are secured to prevent contact with propeller blades.
Boot the sensor
- The sensor will boot up as soon as power is connected. Wait for blinking green lights on the AIS, indicating images are being saved and the sensor is ready for flight (approximately 15 seconds for boot-up and GPS lock), before taking off.
- The AIS sensor must have an unobstructed view of ambient light during startup. Make sure no one is standing over the aircraft or shading the AIS sensor during the bootup cycle. Keep the aircraft stationary on level ground until the AIS indicator light blinks green. Keep the aircraft away from large metal objects which may interfere with GPS lock during bootup.
Land, shutdown, and download data
- Upon landing, press the soft shut down button on the AIS sensor, wait for the AIS LED to illuminate green, yellow, red lights simultaneously. After one second, all three lights will turn off indicating successful shutdown, then disconnect the battery from the field sensor.
- Bring the field sensor, with AIS connected, to a computer with SlantView installed and connect via Ethernet cable (1p, 2i, 2p). Reconnect power to the sensor, and once the LED on the AIS starts blinking yellow (acquiring GPS), use SlantView to connect to the sensor as described in the section Download Data from Sensor. Once connected to SlantView, the sensor will enter low power mode. In low power mode, it is okay to leave the sensor on for extended periods of time without cooling airflow.