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I need a GPS module to include in my quad-copter for providing GPS based navigation. I found there are many GPS modules available, and there are different kind of information available in their specs.

I'm not sure which module will suit for my need. (Probably it'll need to have a very high accuracy, eh ?)

Please help me with selecting a proper module? I'm currently interested in Skylab GPS Module MT3329 SKM53. It's just $24.48 in eBay. (budget is also an issue :D ).

Will that suit for my need? Or any (better) alternative? (hoping to go with Arduino, if that matters)

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closed as off topic by Leon Heller, Dave Tweed, Brian Carlton, Olin Lathrop, Kaz Dec 17 '12 at 16:37

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  • \$\begingroup\$ How fast and far can a quad copter travel? \$\endgroup\$ – Garrett Fogerlie Dec 11 '12 at 8:09
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    \$\begingroup\$ Don't know whether the above module will suit. But if you use it you'll have to use a separate compass module too.. \$\endgroup\$ – David Dec 11 '12 at 8:17
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    \$\begingroup\$ Well first you'll need to actually decide how accurate module you need. Is it going to be the only navigation device? How accurate the position needs to be? In general, civilian GPS isn't going to be very accurate. Another important thing is update rate. That module has update rate of 1 Hz and to me that looks a bit on the slow side. Also since you plan to move the quadcopter around 1 km, you're going to need higher speed than 1 m/s. That won't even be able to resist usual wind. With higher speed, you'll need higher update rate. Also +1 for the compass idea. \$\endgroup\$ – AndrejaKo Dec 11 '12 at 8:21
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    \$\begingroup\$ @Anubis Unfortunately, I can't recommend you a good module since I didn't do any serious research on the subject. :( Keep in mind that there's the mass factor as well which needs to be taken into account. Another point is the current. Many modules I've seen use around 50 mA for operation, which is quite a bit more than the linked module. As for speed, well if you can keep the copter stationary outside with 1 m/s speed, then you're lucky. Weather is much more problematic in my region. Also the speed will make an impact on the update rate of the GPS module if external factors aren't a problem. \$\endgroup\$ – AndrejaKo Dec 11 '12 at 8:41
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    \$\begingroup\$ You might like to ask this on The Robotics Site. \$\endgroup\$ – Rocketmagnet Dec 11 '12 at 14:45
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Using GPS based navigation alone is unlikely to yield the precision and control rate sufficient for navigating a quadricopter. This is not merely due to limitations in the quality or precision of GPS modules, but the inherent and by-design low precision data as available on civilian GPS signals from the satellites.

Besides, if the quadricopter were to lose "visibility" to the satellites for any period, such as when flying under trees, inside buildings, or under heavily overcast clouds, the navigation system goes for a toss.

What you need to be considering is an Inertial Measurement Unit (IMU) module, perhaps one with "11 Degrees of Freedom". While the DOF term is largely misused marketing buzz, the so-called 11-DOF IMUs typically will include a GPS, as well as magnetic compass and gyroscope for navigation, and perhaps also a barometer for altitude sensing. Prices are not very friendly though.

In order to keep costs down, the alternative is to use a basic (6-DOF) IMU and a separate GPS module, both connected to your Arduino, with code to process and utilize this sensor data for navigation. A quick web search would yield many blogs and tutorials to help you put this all together.

Sites like SparkFun, SeeedStudio and AdaFruit offer IMU and GPS modules that work with Arduino.

Some additional research is suggested before actually starting to order the parts.

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  • \$\begingroup\$ Hmm... it doesn't seem like a IMU would provide the kind of relevant data besides what is already needed if using a "perfect" GPS like technology. How would this work? Altitude, direction facing, and tilt would all work, but I think the OP is more talking about latitude/longitude. If you had both of those accurate then you could just remember what to do at those specific coordinates. Edit: Would an Indoor Positioning System (IPS) work (doesn't have to be indoors)? I don't know how easy it is to make one... :/ \$\endgroup\$ – Anonymous Penguin Oct 19 '13 at 20:08

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