Keeping up with a garden can be difficult and time-consuming, particularly if you have a large garden — even more so if you have a farm. Checking on every individual plant yourself requires a lot of labor, and a plant’s health isn’t always obvious just from looking at it with your unaided human eyes. Fortunately if you can see in the infrared spectrum, it becomes a lot easier. To do that on a large scale, you can follow Imetomi’s tutorial to create a tricopter drone to inspect your plants.
Imetomi built this to monitor the garden at his family’s weekend house — a situation most of us find ourselves in. It’s easy enough to keep up with the plants at your weekday house, but the weekend house’s garden tends to be neglected. Imetomi already had spare drone parts on hand, and so he used those to craft a tricopter that can fly over the garden. This same process could also be done with a quadcopter, or any other style of drone, but Imetomi prefers to fly tricopters. Those have different flight characteristics, longer flight times, and have the additional benefit of being easy to fold for storage.
To inspect the plants, Imetomi equipped the tricopter with a Raspberry Pi Zero W and a NoIR Raspberry Pi camera. That camera doesn’t have an infrared filter, so it can see the infrared light reflected by the plants that isn’t normally visible to us. That light corresponds to their health. An infrablue filter is used to alter the spectrum and make it more useful with the RGB color channels from a digital camera. All you really have to do is assemble your drone, attach the camera, and then record video of your garden. You can then look at the video to see color anomalies that indicate a specific plant is unhealthy. If you want to automate the process, you can use flight controller software like ArduPilot to have your drone fly along a preset path.