Drone technology has the potential to change the way farmers scout their fields for things like disease issues and pest pressure. The technology appears to have come a long way in a relatively short time, but there’s a more basic question to ask first:
How does it work?
“If you’re a farmer who wants to use a drone, it’s like having a 200 foot ladder to survey your field,” said Ian Smith, Business Development and Marketing Manager for DroneDeploy of San Francisco, California. “Usually a farmer would take some pictures of the field, but just pictures won’t get you a lot of useful information.”
Smith added, “Instead, you need to create maps.”
The Drone Deploy software includes an app for smartphones.
“You can connect your smartphone directly to the drone with the app,” Smith said. “Our software lets you create aerial maps, 3D models, and images of your entire field. The images will be zoomable, high quality, and high resolution.”
The smartphone is hooked into the drone control unit through a USB port.
“When you open the app up, it’s connected to the drone,” Smith said. “You then draw on a base layer map and your drone’s GPS location shows up, similar to what you’d see on Google Maps to figure out where you are. Our app allows you to draw boundaries on a map that will show the drone where to go and take pictures.”
Basically, the farmer drags the corners of a box to outline the area to survey, and hits okay. A split second later, the software draws up a flight plan.
“The drone runs through a few flight checks, and then it automatically takes off straight up into the air,” Smith said. “It then starts to fly through the designated area and takes pictures. It surveys the field through waypoints on the map, getting good overlap between pictures. It then lands in the exact spot it took off from.”
He said the farmer never has to touch the drone’s joystick. The app pilots the machine automatically.
“When the drone lands,” Smith said, “you pull an SD card out of the drone. It’s similar to a card you’d find in a digital camera. You take it out of the drone and pop it in your computer, where you upload all those images to the Drone Deploy system. The system uses a photogrammetric stitching process to bring all of the pictures together into one high quality image.
“It’s basically like having your own Google map of your farm field,” Smith said.
How high the drone will fly depends upon how much area you need covered in the map.
“There’s a default altitude that we set,” Smith said, “usually 250 feet above ground. Changes depend upon how big your picture needs to be. If you have a 400-acre farm, you’d probably want to fly higher than that because you have more ground to cover.”
Flying higher to cover more ground can actually save on battery life for your drone.
“If you adjust parameters, such as height, with our app, it will update in real time how long that flight is going to take,” Smith said. “If your drone has a battery that lasts 20 minutes, and you adjust it to fly higher, it covers more ground in shorter time. The flight time then will drop in real time, so you make sure you have enough battery for each flight.”
The actual stitching process of your photos is entirely automatic.
“Even when we’re all asleep here in San Francisco (company headquarters) and someone is making a map in Australia,” Smith said, “it’s all automated. No one has to be awake at all.”
Once the images are uploaded, then it’s time for a farmer to wait.
“You go grab a cup of coffee, or whatever,” Smith said. “Depending upon the size and quality of the images you collect, in a couple hours, you’ll get an email saying your map is done. Once you click on the link, you’re right in your high quality, high resolution map that same day you took the pictures.”
He said same-day data is important for farmers, as things can literally change overnight due to events like severe weather.
Turnaround time on getting the stitching process done rarely takes more than a few hours.
“It all depends on things like how many pixels are in each image,” Smith said. “For example, a high end camera can take 60-75 seconds per image to process, so if you throw around 50 images in there, you’re probably looking at around an hour turnaround time.”
Even if the system is processing a large number of maps, you’ll still get your map back in a short time.
“With the horsepower we have in our big servers,” Smith said, “even if we’re processing 50 maps, you’ll still get your map back relatively quickly.”
High-end drones can run up to $3,000, but he said you don’t have to spend that much to get a good map, but there is a baseline recommendation.
“The lowest you may want to go if you’re getting into this today is probably $1,000,” Smith said. “However, 6 to 8 months from now, you’ll probably be able to spend $800, and a couple years from now, it’ll be lower than that.”