Choosing a drone can be overwhelming, with so many options available at such a varying price range. It can be hard to navigate what all the features are, what they mean, and whether they’re something you need or not. One feature that is common on most mid-range consumer drones, but not on lower-tier toy drones is GPS. Perhaps you’re wondering what GPS will do for you and whether it’s worth the extra cost to get a drone that has it.
GPS drones are equipped with a GPS module that allows them to know their location relative to a network of orbiting satellites. Connecting to signals from these satellites allows the drone to perform functions such as position hold, autonomous flight, return to home, and waypoint navigation.
Having GPS on your first drone may not be essential, especially if you’re looking for a very basic drone that you don’t mind crashing a time or two (or more!) as you’re learning. But you might find that having GPS on your drone is more affordable than you think. And the advantages that GPS offer in terms of ease of flight and more advanced smart features more than make up for the slight increase in cost.
Table of Contents
1. How it works
2. How it helps you fly
3. Why You Might Not Want or Need GPS
4. Conclusion
How It Works
GPS is the same system that we are all familiar with in road navigation systems. A global network of orbiting satellites sends signals that a GPS module picks up with a radio receiver. These signals allow the module to determine its position, speed, and time. GPS uses the concept of triangulation to determine relative position and speed, typically using three or four satellite signals, although some drone GPS modules will lock on to up to seven or eight separate satellite signals for optimal performance.
There are several different worldwide GPS systems. Within the US, the GPS network of satellites is distributed so as to ensure that at least four satellites are theoretically visible from any given point on the land surface. Russia operates the GLONASS GPS system of satellites, and Europe is in the process of developing the Galileo GPS system. China is also developing its own GPS network, the BeiDou, while India is developing the IRNSS GPS system.
Some GPS modules on drones are capable of receiving signals from any of these sources, though most are limited to a single system. Having access to a greater number of signals and systems can increase accuracy of positioning, and thus all the GPS dependent features of your drone. Especially if you plan to travel with your drone, you may want to look specifically for a GPS drone that can receive signals from other systems. Your standard GPS drone will have position location accuracy of a meter or so, while more advanced GPS drones can have accuracy of up to a centimeter.
How It Helps You Fly
GPS technology has improved enough over the past few years to make it both affordable and lightweight enough to be more or less standard in your average consumer drone. Even some of the drones that would fall in the toy category come with GPS functionality. Having GPS on your drone makes a big difference in how it performs. It plays an important role in many of the features that pilots have come to rely on. Check out the following ways GPS helps out drone pilots.
Position Hold
When the drone can lock on to a GPS signal, it is able to identify and maintain its position at a fixed location. You could also call this the ability to achieve a stable hover. If you are not feeding the drone any controls at all, with GPS it will be able to stay in place even under a moderate breeze. If it identifies that it has drifted away from its original location, it will automatically correct and return to the same spot mid-air.
The same principle applies to achieving more stable flight. A drone without GPS is much more blown off course by breezes, and the pilot has to work much harder to maintain a straight, smooth flight path. The GPS, however, helps the drone to stay on course much more smoothly and steadily by identifying where it is.
Altitude Hold
Some drones also use GPS to hold a steady altitude while in flight. This is especially important given the FAA regulation that drone aircraft must operate below 400ft Above Ground Level (AGL). Many GPS drones will have this altitude limit pre-programmed in the flight controls. However, many drones actually use onboard barometric sensors to determine altitude, or imaging sensors to determine proximity or distance from objects directly below, so altitude hold is not necessarily dependent on GPS. It depends on the drone. Either way, holding a steady height in manual flight (without GPS or other sensors) can be quite a challenge.
Return to Home
The return to home feature is one of the best friends of a beginner pilot (and more advanced as well!). The drone will remember and return to its exact take-off location, to within a foot or two. This is obviously only possible with GPS to tell the drone where it is at any given time, and where it started from.
Return to home becomes important if your battery power runs low, you’re reaching the outer range of connection to your controller or you’ve gotten disoriented at the controls and don’t know how to get your drone going back in the right direction. Some drones will have an automatic return to home function kick in if the battery gets too low or your controller signal is interrupted. Almost all GPS drones have a button that will automatically send the drone back to its take-off point.
Reporting
Many GPS drones create a flight log of each flight – how long you flew, where you flew, etc. This can be helpful just in terms of record keeping, but it is also helpful in locating and recovering a crashed drone. You can access the flight log through your controller or controller app, and determine the last known GPS location. Chances are your drone will be there, or somewhere not too far off.
Waypoint Navigation
If you would like to preplan a flight path or mission for your drone, this can be done by directing it to navigate to specific GPS coordinates along the path, called waypoints. A GPS drone can use autopilot function to travel along the path that you have predetermined. Autonomous flight instructions at the waypoints can also direct the drone to hover for a set amount of time at each location.
You might do this if you want to get pictures of a specific area. For an aerial photographer, if the drone is set on a predetermined course and flies it without any need for input from the controller, the pilot can focus on working the camera for the shot you want. The autonomous flight is likely going to be smoother than any manual control can achieve, and will therefore also deliver smoother, clearer camera images.
Many commercial sectors heavily rely upon waypoint navigation in drone technology. GPS is absolutely essential for the use of drones in mapping, inspection, construction, agriculture, and more.
Mapping?
This is not a flight assist feature, but as a side note, if you are hoping to use images with any 3D mapping or photogrammetry software, GPS on drones is essential for the geo-tagging of images to create the maps.
Why You Might Not Want or Need GPS
GPS is not a perfect solution for smooth controlled flight in all situations. There are some factors to consider of how GPS can either cause frustration or harm, or just not be practical or helpful. In those situations you might prefer a drone that does not have GPS, or has the option to turn it off. This could either be achieved by going low-end (think, cheap drone), or else going really high end and relying on other types of location determining methods. Take a few of the following for instance.
Battery Drain
GPS in a drone drains the battery faster. There’s no way around it. If you have a small drone with a small battery, the extra weight and extra technology needed to operate the GPS module will bring down the battery life. However, for all intents and purposes, drones these days that are not equipped with GPS are going to have a relatively shorter battery life compared to a standard consumer drone, just because they are cheaper and have smaller batteries anyway.
Higher Cost
Drones with GPS are going to cost a bit more than drones without it. Partly it’s the GPS module, but mostly it’s all the other technology that has to go in to make use of the satellite signals – the hovering stability, the return to home, all the other intelligent features need programming, and that equals higher cost.
Potential Complications
The GPS dependent functions on the drone rely on the signals they are able to receive. Sometimes there can be a delay in the signal, or the GPS module can switch between signals mid-flight and confuse the drone about its actual location, possibly leading to a crash or flyaway. However rare these cases might be, if it happens to you, it’s sure to be extremely frustrating.
Another complication is that many GPS drones will look for simultaneous connection to three satellites, or may not even report as being ready to fly until seven signals are detected. While this is presumably to achieve optimal flight, you just might be in a location that can’t pick up that many satellites, and you’re left grounded. So would it be better to fly without any GPS, or to not get off the ground at all because you can’t get enough signals? A frustrating choice.
GPS-denied Scenarios
There are certain situations where GPS is simply not available, but drones are needed that will have high levels of location precision and accuracy. Most of these scenarios involve commercial or professional applications of drones, and they can get around the lack of GPS with other sophisticated sensors and programming. Some of these situations include:
- Indoor inspections – If a drone is flying inside a warehouse, or inside an asset such as oil tanks or industrial boilers, chances are small that it will be able to find GPS signals with any degree of reliability.
- Mining – GPS signals can’t get underground, so again, drones are not going to be able to rely on GPS for location.
- Bridge or Building Inspections – Large metal objects can obstruct the GPS signal, causing problems for the drone’s ability to operate reliably.
- Critical Infrastructure or High Security Locations – There is some concern for the security of GPS signals, and for that reason some government agencies are hesitant to utilize GPS for drone operations near places such as military bases or power plants.
In these types of cases, high-end professional drones utilize a variety of methods to achieve stable flight, hover in place, and “know” its relative location in space. The most common method is obstacle avoidance sensors that provide the drone with reference points, giving it the ability to hold itself steady in relation to them. Another approach is a system called SLAM (Simultaneous Location and Mapping) by which drones make use of sensors to create real time maps of their surroundings and navigate by them.
Conclusion
If you’re ready to spring for a GPS drone and all the benefits that GPS technology can offer, there’s still a big decision to be made, such as how much do you want to spend, what kind of intelligent features are you interested in, and what quality of camera are you looking for. Below are several of the best consumer GPS drones. For our most recent recommendation on the best GPS drone, visit our buying guide.