Turn Your Mavic 2 Pro into a Mapping Machine with these Accessories
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One of the most common questions we get asked is what type of drone to buy for mapping projects. For people who are just getting started, one of our go-to recommendations is the Mavic 2 Pro. But to unlock its full potential as a mapping drone, you need some important accessories.
A Great Little Drone
Equally important for mapping, the Mavic 2 Pro performs like a champ. It's very stable in flight, has 10 obstacle avoidance sensors on all sides, and its 20-30 minute flight time lets you map ~50 acres from 400 ft with 80% overlap. For icing on the cake, it's clever folding design makes it one of the most portable drones out there.
Note: before going further it's worth mentioning here that not all Mavics are created equal! The Mavic 2 Zoom, Mavic Air 1 & 2, and mini-Mavic are cousins of the M2P, but we do not recommended them for mapping. They all have their niches, but mapping isn't one of them. These drones either have inferior cameras, lack the capacity to fly waypoint missions (which for mapping is a deal breaker), or other performance tradeoffs related to their weight and size. If you're interested in mapping, go with the Mavic 2 Pro.
Out-of-the-box, however, you won't get very far with the M2P base package. Like most drones, the key to turning your M2P into a mapping machine lies in getting the right accessories. Of course you'll need extra batteries, but that's just the beginning.
Overcoming Limitations of the Little Controller
Drone apps like DJI GO 4, DJI Pilot, Pix4Dcapture, present lots of information on the screen at once. You don't want to be squinting at the screen during a flight looking for an indicator. And you definitely don't want to accidentally click the wrong button, which is easy to do when they're so close together.
Tip: If you plan to do mapping projects with your M2P, try to get the version that comes with a DJI Smart Controller which has an integrated tablet. It cost about $500 more, but you won't need to use your phone or a separate tablet, or fiddle with mounts and cables.
The other limitation of the controller, also related to its small size, is its limited battery life. The battery is not only constrained by the small size, but also by the fact that the controller actually provides power to whatever phone or tablet you have connected. Expect on average about 2 hours of usage on a full charge, which goes by very quickly. When the controller battery gets below around 15%, it will start beeping at you. If it gets too low and shuts off during a flight, your Mavic will have to find its way home on its own.
Fortunately, there's an accessory for that. With the right accessories, you can mount a tablet on the controller, and hook up an external battery to power the controller during flights.
Top 15 Mapping Accessories for the Mavic 2 Pro
Below are the top 15 accessories we recommend for the Mavic 2 Pro:
1. Extra batteries. In theory, a fully charged battery can fly the Mavic for ~30 minutes. In practice, you'll get a lot less than that for your mission, because the drone needs to launch, climb to altitude, and go to the first way point before it can start the mission. You also need to reserve enough for it to get back home - with a healthy safety buffer of at least 15-20%. Hence you'll probably be limited to more like 15-20 minutes of flight over the target.
Get as many extra batteries as you think you'll need. Intelligent flight batteries run about $150 each. The DJI Mavic 2 Fly More Kit includes two extra batteries as well as a number of useful accessories (below).
2. Multi-battery charger. The Mavic 2 Fly More kit includes this 4-battery charging station. The good news is that it uses the power supply that comes with your M2P, so you don't have to buy another one of those. The bad news is that this station charges batteries in series, not simultaneously. So it can still take a while to charge several batteries, but at least you don't have to monitor it.
3. Battery to USB Adapter. This little gizmo comes with the DJI Mavic Fly More kit. It clips on to the end of one of your batteries and gives you two USB ports to charge your tablet, controller, and other stuff. I prefer to use my flight batteries exclusively to fly the drone, rather than charge other devices, but its still a useful accessory.
4. Tablet. An 8-9" tablet is a good fit for the M2P controller. That gives you a much larger screen to plan your flight, but doesn't make the controller too unwieldy to hold. Larger tablets can be challenging to mount and obstruct the controller's screen and joy sticks. Pictured here is an 8" Samsung Galaxy Tab S2. An iPad mini would fit well also (tip: if you want your iPad Mini's to have GPS location services, you have to get the cellular enabled version whether or not you need the cell service). As with any mobile device, look for mid to upper-range tablets that are sturdy and can withstand some heat so it won't freeze-up on you, and don't overload it with apps.
5. Tablet holder. There are a few tablet holders for the Mavic controller, such as the one here. They all essentially fit into the phone slot and have a clamp sticking out to hold the tablet. Some of them can hold tablets as large as 12-14", but as noted above the sweet spot for this controller is the 8-9" range.
6. USB cable to power the controller. Due to its small size, the controller only lasts a couple of hours on a battery charge. To make matters worse, when connected to a tablet the charger actually provides power to the mobile device, draining its battery even faster.
To avoid getting grounded as you wait for your controller to recharge, you may want to recharge it while in flight. That's where this micro-USB cable comes it. It plugs into the micro-USB port on the left side of the controller. Usually that's the port that connects to your phone, presenting a minor dilemma. If the left port is needed for power, where do you connect your phone or tablet? The answer is you connect your tablet to the full size USB port on the bottom of the controller (see below).
For the power supply cable, we recommend getting one that has an angled end (like this one), which makes it less likely to pull out during a flight.
7. Power pack. Bring an external power pack to charge your controller and tablet if needed. This may not be necessary if you're only flying for an hour or two, but if you're trying to cover a lot of area you will likely need to charge up your controller and/or tablet to make it until the end of the day.
Some people also bring a high capacity power supply or even a generator in order to charge drone batteries in the field. We have found this isn't always practical, because even with a charging system you have to wait for a battery to cool down before you can plop it in the charger, so the whole process can take a couple of hours or more. But if you're flying for several hours this could get you a couple more flights at the end of the day.
8. USB cable to connect the tablet to the controller. This cable connects the tablet to the controller, using the USB port on the bottom of the controller. Get one that matches your tablet, but it only needs to be 30cm or so. We recommend one with a u-shaped end so it doesn't pull out of the tablet during a flight (and can be taped down if needed). The one shown works well with the Samsung Galaxy Tab S2, but check the micro-USB port on your tablet before you buy to make sure the u-shape goes in the right direction.
9. Extra memory cards; memory card reader. If you'll be doing multiple flights in a row, odds are you'll want to pull images off the drone between flights. Extra memory cards will allow you to exchange cards quickly without having to wait to move the images onto a laptop between flights.
10. Extra props. Have at least one extra sets of props so you don't get grounded if a prop gets nicked or damaged on landing (not uncommon). The DJI Mavic Fly More kit includes an extra set of props.
11. The DJI Mavic 2 Fly More Kit. The Fly More Kit ($400) from DJI includes two batteries, extra props, and many of the accessories referenced on this page. Everything it comes with can fit in this well-designed bag. Although not cheap when you consider everything you get it is well worth the price tag.
13. Hotspot. An Internet connection in the field is not absolutely critical, but it sure does make planning your mission a lot easier. Hopefully you will have done all your firmware updates the day before, but you may still need an Internet connection to view background imagery in your flight planning app, get clearance from the local airport through LAANC, check weather, monitor air traffic control, etc.
You can turn your mobile phone into a hotspot, although be aware that can run down your battery pretty quickly. A standalone hotspot won't tie up you or your phone.
14. Tablet hood. There's nothing worse than not being able to see your tablet while you're trying to monitor a flight because the sun is creating glare on your screen. This is actually fairly common, because general best practice is to fly with the sun at your back so you can keep an eye on the drone without having to squint into the sun. Be sure you know how to control your screen brightness (and disable auto-brightness if your tablet has that).
The best solution is to use a super bright tablet, like the ones built in to smart controllers. If you're using a regular tablet, a hood can help tremendously. There are a few vendors who sell these in a variety of sizes and designs. Be sure to get one that will fit your tablet and has the right cutouts for your holder and cables. Making one out of cardboard is certainly possible also.
On a related note, if you wear polarized sunglasses you may very well find your tablet looks completely black even at full brightness. This is because many screens give off polarized light, which depending on the phase shift your glasses will cancel out. The solution is to tilt your tablet (or your head) 90 degrees, or take your shades off!
15. Landing pad. Landing pads not only look cool, they also help reduce the amount of dust that blows onto your drone during launch and landing. This is particularly important in mapping projects, where a bad smudge of dust on the lens can ruin your data. They can also prevent a rogue blade of grass from wrapping itself around the propeller of your Mavic, and flipping it over.
For the Mavic 2 Pro and other modern drones that feature a downward obstacle avoidance camera, a landing pad can also provide an excellent image for automatic landing. DJI calls this Precision Landing. The way it works is the drone takes a photo of its launch point shortly after launch (make sure to take it straight up for the first 20 feet), and then uses this image to fine-tune its landing. The Mavic 2 Pro is a stellar lander in my experience, routinely landing within a foot of where it started on the lauch pad.
And everything else...
In addition to all the above accessories which are pretty specific to the Mavic 2 Pro, you'll probably want some other generic accessories in your flight kit. Below are some that I like. If you have others, make a note in the comments!
This work was supported by the USDA - National Institute of Food and Agriculture (Hatch Project 1015742; Powers).