Join Jim Heid for an in-depth discussion in this video Calibration, part of DJI Mavic Pro: Tips, Tricks, & Techniques.
- Now let's talk about the world of calibration. There are a few components in the drone that you're able to calibrate. We've already looked at one, the Gimbal. Let's look at another one that's even more important, compass calibration. As we saw earlier in this course, the Mavic's compass helps the drone get its bearings and keep its bearings. Knowing that, it's easy to see why an accurate compass calibration is pretty important. But calibrating the compass isn't something you need to do all the time, and when you do, it's critical to do it right. Let's talk about both halves of that equation.
It used to be that experienced pilots recommended calibrating the compass every time you got to a different flying location. Some pilots still do that, but DJI doesn't recommend it for the Mavic. Generally, you should calibrate the compass only what DJI GO tells you to. That's my approach. So that's the when. Here's the where, why and how. The where is hugely important. It's best to calibrate the compass in an open grassy area, away from any sources of magnetic interference. Cars, power lines, and as I mentioned early on in this course, not when you're standing on pavement, which could have metal mesh in it.
Keep any metal at least 10 feet away from the drone when you calibrate. That includes your watch, your phone, and the Mavic's remote controller. The calibration process basically causes the drone to measure the magnetic fingerprint of the area. If you calibrate in an area of magnetic interference, the drone might report that the calibration was successful, but what it isn't telling you is that it was inaccurate. And that is a sure fire way for something to go wrong once you fly. Okay, so that's the where. You've probably seen the how in DJI's videos, or on YouTube, but let's cover it here too.
Go into the Aircraft Status settings, and in the Compass area, tap Calibrate. Confirm that by tapping OK, and then step away from the controller and your phone and do the famous calibration routine. Rotate the drone horizontally, then turn the drone vertically so the camera is facing the ground and rotate it again. Do both rotations as smoothly as you can. It's this rotation process that enables the drone to take that magnetic fingerprint. It's easy to do, but that doesn't mean you should do it all the time.
Some pilots will disagree with me, but I say follow DJI's rules, and do it when the drone tells you to. Another component that can need occasional calibration is the inertial measurement unit. The IMU, that part of the drone that has the accelerometers, the gyros and barometer. You might need to re-calibrate it after a nasty crash or a lot of jostling. Or if you notice the drone flying askew instead of straight. Some people also re-calibrate the IMU after updating the drone's firmware, but I never have.
And the reason I'm not quick to calibrate the IMU is again, because calibrating doesn't necessarily equal accurate calibrating. My Mavic was calibrated at the factory, and it flies beautifully. Should that change, then I'll calibrate the IMU. Heres' a look at the basic process. Power up your remote controller and the DJI GO app. Then fold up the drone and put it on a completely level surface. That's critical. Then power it up. By the way, don't trust a leveling app in your iPhone or tablet.
Because those apps rely on the accelerometers on the phone or tablet. And who says those are precisely calibrated? After the drone is connected and warmed up, go into the Main Controller settings, that's the little drone icon, then go to Advanced settings and sensors. Then tap the calibrate IMU button. Now here's where we're going to get off the bus, but if we were to continue our ride, we tap start calibration and the DJI GO app will have you hold the drone in several different positions. On its side, upside down, and standing on what I guess is its head.
Do that as gingerly and precisely as you can, and you're done. One more IMU calibration tip. It's best to do an IMU calibration on a drone that hasn't flown for at least a few hours. This will help the drone start up faster. Remember early on it this course when we talked about the IMU warming up after start-up? That's what it's doing. Warming up to the same temperature that it was at when it was calibrated. To get those faster warm-up times, some people recommend storing the drone in a cool basement or putting it in front of a air conditioner for a while before calibrating the IMU.
Don't put it in the refrigerator, yes people have done that. What's most important, is that you don't calibratedthe IMU in a drone that's warm from a recent flight. There's one other system in the Mavic that can be calibrated. Though again, can doesn't mean should. I'm talking about the Mavic's vision system. Its collision avoidance cameras. If the DJI GO app reports a problem, re-calibrating the vision system might be in order. To do this, you need to use the DJI Assistant software which runs on Macs and Windows PCs.
So you need to download this from DJI's website, and honestly, the versions I've used are not the most robust. A look on the Mavic's pilots forums shows that it can be tricky to get running. The Assistant software is an important tool for getting deep into some aspects of the Mavic's operation, and we can only hope that it'll get more polished over time. Anyway, once you have it installed, connect your Mavic to your computer using a USB cable with a micro USB connector at one end. You can use the cable that comes with the Mavic's battery charger.
When you launch the Assistant and turn on the drone, you'll see the model appear on the main screen. Click it and several different options appear. Click calibrate and a little three screen tutorial appears that previews what you are doing. Again this is as far as we're taking this training 'cause my vision sensors are working just fine thank you. But basically, you're aiming the drone at a screen full of patterns and circles, and the drone's doing lot of number crunching to calibrate its sensors. There are a few other things that you can do with DJI's Assistant software.
You can use it to down-grade your firmware to an earlier version, if you're having problems after an update. And maybe most significantly, you can use the Assistant software to access the flight logs that the drone records when in flight. This is a kind of blackbox system that the drone has. And when a crash occurs, that data can be analyzed to try to figure out where things went wrong. Now covering these details would be a course all by itself, so I'll instead refer you to a great website called airdata.com. It's a data analysis service for drones.
You can try it for free and subscribe to it if you want. And it has some great tutorials on accessing flight logs.
- Safety checks
- App settings
- Startup, takeoff, and landing
- In-flight data displays
- DJI GO tips
- Flight modes
- Streaming live
- Adjusting focus
- Exposure and white balance
- Still photography and panoramas
- Shutter speed
- Aerial video
- Using the gimbal
- Using the remote controller