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Users => Applications - Autonomous Flight => Topic started by: startrek66 on August 09, 2016, 04:08:01 pm

Title: Gps for Revolution
Post by: startrek66 on August 09, 2016, 04:08:01 pm
I want to buy a GPS for revolution board. I'm not interested in the autonomous flight, I'm happy to use the GPS just to maintain the position. I do not have much knowledge, and unfortunately there are many products that are sold with compatibility to fc revolution and with very different prices, and then you create the confusion. I ask you what are the minimum requirements that must have a GPS to be mounted on fc revolution and if there is a list of GPS products that have already been successfully tested.
Thanks in advance
Title: Re: Gps for Revolution
Post by: f5soh on August 09, 2016, 04:24:13 pm
Naza GPS is a good choice, original or clone like that:
http://www.banggood.com/Ublox-M8N-GPS-Compatible-with-DJI-NAZA-Lite-V1-V2-Flight-Controller-Phantom-1-2-Vision-p-991718.html
That allow GPS and also receive external Mag data using the same serial connection.

Naza GPS is currently supported using the Next branch, 15.09 release only support external mag from original OP GPSv9.
Title: Re: Gps for Revolution
Post by: Mateusz on August 09, 2016, 04:43:30 pm
Just one comment:

It is important to consider what GPS will be used for and why it is needed. I am perfectly happy without GPS for the type of flying I am doing right now. Altitude vario and it hovers more or less in place, I can let sticks for few seconds that is enough to put goggles on and tighten the head strap before it starts drifting.


Something to think of :)
Title: Re: Gps for Revolution
Post by: startrek66 on August 09, 2016, 06:16:40 pm
Thanks for your answers.
I agree that the GPS does not solve the stability problems . Luckily for me my quadcopter  is really stable with flight mode that I use usually ( attitude , altitude hold) . The gps interests me to take pictures .

With reference to naza gps clone I noticed that only has a cable while I saw other GPS models with two cables that connect to the Main and Flexi ports . What are the differences ? Thanks

Example gps one cable

 http://m.aliexpress.com/item/32630075400.html?productId=32630075400&productSubject=UBLOX-NEO-7M-NEO-7M-GPS-w-Compass-Stand-Holder-For-CC3D-Evo-CC3D-Revolution-Flight&spm=2114.46010408.3.67.sIkj1n&tracelog=wwwdetail2mobilesitedetail

GPS with two cables

http://m.aliexpress.com/item/32703991313.html?productId=32703991313&productSubject=U-blox-NEO-7N-GPS-with-3-Axis-Electronic-Compass-for-CC3D-Revolution-Flight-Controller&spm=2114.46010408.3.19.WjLEBX&tracelog=wwwdetail2mobilesitedetail


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Title: Re: Gps for Revolution
Post by: f5soh on August 09, 2016, 07:20:59 pm
Quote
That allow GPS and also receive external Mag data using the same serial connection.

Others GPS with 2 cables uses one serial cable for GPS and another I2C connection for Mag.
So with one cable that more simple, avoid I2C issues and flexiPort/mainport is free for RC Input use like DSM/Sbus
Title: Re: Gps for Revolution
Post by: hwh on August 09, 2016, 08:42:55 pm
« Last Edit: Today at 01:26:31 pm by startrek66 »
« Reply #4 on: Today at 01:20:59 pm »
It's usually a bad idea to edit a post after it's been answered.  It would have been better to put the links in a new post. f5soh will never see that you changed your post and others may ignore it because it was answered by f5soh in it's original form.

You can certainly buy a cheap GPS without a mag sensor like your first link and try to use the revo's built in mag sensor but that almost never works right.  You might get lucky and find that it has the sensor but no cable and be able to add a cable but even then you still have all the disadvantages of an I2C external mag.

Your second link has the connector for an I2C mag and should work fine.  I don't recommend buying them for two reasons: First, they take up both the main and flexi ports which limits your options for receivers, OSDs, etc...  Secondly, the I2C ones are often hard to get running reliably.

Following the advice you were given to get a DJI/Naza style GPS is the easiest, most reliable way to add a GPS.
Title: Re: Gps for Revolution
Post by: TheOtherCliff on August 09, 2016, 08:55:26 pm
All of these require you to solder a different connector on them.

Some GPSs have both a GPS and a mag.  Get one that has both.  This "aux mag" can be placed on a pole to get it farther away from the mag fields of the high current motor ESC battery wires.  That allows it to see the Earth's mag field without so much distortion.  You still need to twist all high current (battery, PDB, ESC, motor) wire pairs/triplets.

Some GPSs that have a mag, only have one cable.  Both GPS and mag signal are sent on the one cable.  That is what you should get because it does not need 2 ports on your Revo.  You will want those Revo ports for other things, like OSD, Sbus, etc.

Some of the GPSs that have only 1 cable do not even have a mag.  Stay away from those.

Generally, all of the GPSs that have two cables have a GPS and mag.  These can be used if you already have this type of GPS.  I have one and used to fly it a lot, but they use a different mag signal that is easier to corrupt if the cable is too long, etc.

If I recommend what I think is best right now, it is an authentic DJI GPS/mag.  They are about $70 (shipped, new) on eBay.
Edit: They seem to be cheaper now, down to $43 shipped, new.  I have not bought this, so buyer beware.
http://www.ebay.com/itm/DJI-GPS-Compass-Module-for-DJI-NAZA-M-Lite-Flight-Control-System-/251862698572

Next in line, I would get a DJI GPS/mag clone from eBay for about $22 (shipped, new) if you want cheap, but test it for several days as discussed here:
https://forum.librepilot.org/index.php?topic=449.msg15319#msg15319

In last place, but it still works is a simple uBlox GPS with an I2C aux mag (two cables).
Title: Re: Gps for Revolution
Post by: startrek66 on August 10, 2016, 12:06:20 am
« Last Edit: Today at 01:26:31 pm by startrek66 »
« Reply #4 on: Today at 01:20:59 pm »
It's usually a bad idea to edit a post after it's been answered.  It would have been better to put the links in a new post. f5soh will never see that you changed your post and others may ignore it because it was answered by f5soh in it's original form.

You can certainly buy a cheap GPS without a mag sensor like your first link and try to use the revo's built in mag sensor but that almost never works right.  You might get lucky and find that it has the sensor but no cable and be able to add a cable but even then you still have all the disadvantages of an I2C external mag.

Your second link has the connector for an I2C mag and should work fine.  I don't recommend buying them for two reasons: First, they take up both the main and flexi ports which limits your options for receivers, OSDs, etc...  Secondly, the I2C ones are often hard to get running reliably.

Following the advice you were given to get a DJI/Naza style GPS is the easiest, most reliable way to add a GPS.

Of course you're right. I was changing my message while f5soh answered .
Title: Re: Gps for Revolution
Post by: startrek66 on August 10, 2016, 12:15:25 am
Many thanks for your advice , from which I understood that add a GPS to revo is not a simple thing .
So what can you say about these products ?

https://www.youtube.com/watch?v=kFY9LyihBqo&index=5&list=PLYsWjANuAm4o3s930kAW0uCTapF3bo7eE

From the video it seems easy to configure and use.
Title: Re: Gps for Revolution
Post by: hwh on August 10, 2016, 01:10:18 am
I'm not sure what you're looking for, the hardest way to hook up a GPS?  :)

The video shows buying a GPS, buying an FTDI adapter, downloading UCENTER, configuring the GPS for a cc3d instead of a revo, and then finally connecting it to the revo where it will erase the settings you just did and configure the GPS the way it needs it.  In fact, with the tiny "OP GPS" the video shows it doesn't remember any of the settings you do in UCENTER after a couple of hours without power applied anyway.  It has no flash to remember settings or mag sensor.  Those tiny GPS units also have a bad habit of melting as you can see from the attached pictures.

How is all that easier than buying the GPS we recommend and just connecting it to the revo?
Title: Re: Gps for Revolution
Post by: Wagsy on August 10, 2016, 06:51:07 am
Yep. setting up a DJI GPS is the simplest way.
Buy GPS, cut wires, add to a REVO plug, set board to use INS13/GPS, calibrate-set to external mag and fly.
Title: Re: Gps for Revolution
Post by: startrek66 on August 10, 2016, 08:54:05 am
Ok. I search a good price and buy it or a dji gps clone. I ask help you for my choice. Thanks

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Title: Re: Gps for Revolution
Post by: TheOtherCliff on August 10, 2016, 10:57:47 am
I just ordered one of these apparently authentic DJI GPS for $43 shipped.  It looks exactly like my other authentic DJI, including all markings, screw placement, screw head type, etc.  It seems to be the real thing that the seller has sold for $80 in the past (according to the item sales history).

I will let you know if it is and if it passes my tests as well as my other authentic DJI GPS.

http://www.ebay.com/itm/DJI-GPS-Compass-Module-for-DJI-NAZA-M-Lite-Flight-Control-System-/251862698572
Title: Re: Gps for Revolution
Post by: startrek66 on August 11, 2016, 05:15:54 pm
Found three models of gps. What is a good choice?
Thanks

http://m.banggood.com/Mini-Ublox-Neo-6M-GPS-For-CC3D-Revolution-Flight-Controller-wBuilt-in-Compass-p-1022655.html

 http://m.banggood.com/Mini-Ublox-7M-GPS-Module-for-CC3D-Naze32-Flip32-SP-F3-Flight-Controller-p-1042849.html

 http://m.banggood.com/Mini-Ublox-M8N-GPS-Module-NEO-M8N-GPS-for-APM-2_52_62_8-CC3D-SP-Racing-F3-Naze32-Flip32-PX4-p-1035454.html

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Title: Re: Gps for Revolution
Post by: startrek66 on August 11, 2016, 05:16:56 pm
I just ordered one of these apparently authentic DJI GPS for $43 shipped.  It looks exactly like my other authentic DJI, including all markings, screw placement, screw head type, etc.  It seems to be the real thing that the seller has sold for $80 in the past (according to the item sales history).

I will let you know if it is and if it passes my tests as well as my other authentic DJI GPS.

http://www.ebay.com/itm/DJI-GPS-Compass-Module-for-DJI-NAZA-M-Lite-Flight-Control-System-/251862698572
How you test the gps?

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Title: Re: Gps for Revolution
Post by: f5soh on August 11, 2016, 05:48:02 pm
Found three models of gps. What is a good choice?
Thanks

All three are crap. No I2c wires, sometimes no mag chip inside and after added the i2c wires most of them are defective.

Why not just follow advice we give you and buy a Naza Gps, original or clone ?
Title: Re: Gps for Revolution
Post by: startrek66 on August 11, 2016, 09:42:08 pm
Like this?

http://m.banggood.com/Ublox-M8N-GPS-Compatible-with-DJI-NAZA-Lite-V1-V2-Flight-Controller-Phantom-1-2-Vision-p-991718.html



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Title: Re: Gps for Revolution
Post by: f5soh on August 11, 2016, 09:45:26 pm
yes, or similar.
I posted the same link in my first post here.
Title: Re: Gps for Revolution
Post by: startrek66 on August 11, 2016, 09:48:03 pm
Ok very well.  I found only this with ref tu compatibility dji. Thanks

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Title: Re: Gps for Revolution
Post by: Wagsy on August 12, 2016, 12:07:36 am
Yes just simply get the NAZA one.
Put the NAZA GPS up high out of the way, make sure that once you have a good cal, that it does not turn or move from that position or else your mag will be out again.
Mine is on a little foldaway stand, works really well, boots up fast and always arms, I'm impressed.
Title: Re: Gps for Revolution
Post by: TheOtherCliff on August 13, 2016, 06:45:39 pm
I just ordered one of these apparently authentic DJI GPS for $43 shipped.  It looks exactly like my other authentic DJI, including all markings, screw placement, screw head type, etc.  It seems to be the real thing that the seller has sold for $80 in the past (according to the item sales history).

I will let you know if it is and if it passes my tests as well as my other authentic DJI GPS.

http://www.ebay.com/itm/DJI-GPS-Compass-Module-for-DJI-NAZA-M-Lite-Flight-Control-System-/251862698572
How you test the gps?

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I wrote the DJI GPS part of the firmware and before that I wrote test programs that dump out all data and report all errors.

The easiest way you can test is to configure a flight controller to use it, plug these things into a permanent power supply (AC to DC maybe) and let it run without stopping for several days.  If GPS and mag are still working after several days, they have passed the test.  If not, you should find out how long it runs before breakdown (my cheap GPS breaks down about every 24 hours or so) and decide if it is worth the risk.  I have Attitude mode on my flight mode switch so I can recover if GPS stops working.
Title: Re: Gps for Revolution
Post by: startrek66 on August 14, 2016, 10:45:51 am
I just ordered one of these apparently authentic DJI GPS for $43 shipped.  It looks exactly like my other authentic DJI, including all markings, screw placement, screw head type, etc.  It seems to be the real thing that the seller has sold for $80 in the past (according to the item sales history).

I will let you know if it is and if it passes my tests as well as my other authentic DJI GPS.

http://www.ebay.com/itm/DJI-GPS-Compass-Module-for-DJI-NAZA-M-Lite-Flight-Control-System-/251862698572
How you test the gps?

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I wrote the DJI GPS part of the firmware and before that I wrote test programs that dump out all data and report all errors.

The easiest way you can test is to configure a flight controller to use it, plug these things into a permanent power supply (AC to DC maybe) and let it run without stopping for several days.  If GPS and mag are still working after several days, they have passed the test.  If not, you should find out how long it runs before breakdown (my cheap GPS breaks down about every 24 hours or so) and decide if it is worth the risk.  I have Attitude mode on my flight mode switch so I can recover if GPS stops working.
You supply tension from usb connection?


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Title: Re: Gps for Revolution
Post by: f5soh on August 14, 2016, 03:18:06 pm
GPS need external +5V to be powered.

Usb only power board, not external devices connected to Receiver/Main/Flexi ports
Title: Re: Gps for Revolution
Post by: startrek66 on August 17, 2016, 12:07:47 pm
GPS need external +5V to be powered.

Usb only power board, not external devices connected to Receiver/Main/Flexi ports
Thank you for reply.
I followed your advice and ordered a naza gps clone but also a neo - 7n GPS ( really low price )

http://www.ebay.it/itm/252497567144

I change the connector with two jst-sh 4 pin.

To configure the GPS can use the 15.9 version of the gcs or I have to change version ?

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Title: Re: Gps for Revolution
Post by: f5soh on August 17, 2016, 01:16:22 pm
I think you can found the answer in my first post in this thread:

Quote
Naza GPS is currently supported using the Next branch, 15.09 release only support external mag from original OP GPSv9.
Title: Re: Gps for Revolution
Post by: startrek66 on August 17, 2016, 02:31:32 pm
I think you can found the answer in my first post in this thread:

Quote
Naza GPS is currently supported using the Next branch, 15.09 release only support external mag from original OP GPSv9.
Thanks for the reply . I'm not expert in software programming so I think I'll wait a new final version of gcs .


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Title: Re: Gps for Revolution
Post by: f5soh on August 17, 2016, 02:42:59 pm
https://forum.librepilot.org/index.php?topic=1910.0
Title: Re: Gps for Revolution
Post by: startrek66 on August 17, 2016, 02:50:23 pm
https://forum.librepilot.org/index.php?topic=1910.0
In this community you are all very cooperative . Thanks again.

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Title: Re: Gps for Revolution
Post by: TheOtherCliff on August 23, 2016, 09:36:44 pm
$43 (shipped) DJI/Naza Lite GPS

http://www.ebay.com/itm/251862698572

I received mine today.  It's an authentic DJI Naza Lite.  I haven't tested it yet.

You need "next" or the upcoming release to use it, and you must solder a different connector on it.
Title: Re: Gps for Revolution
Post by: startrek66 on August 24, 2016, 08:41:07 pm
$43 (shipped) DJI/Naza Lite GPS

http://www.ebay.com/itm/251862698572

I received mine today.  It's an authentic DJI Naza Lite.  I haven't tested it yet.

You need "next" or the upcoming release to use it, and you must solder a different connector on it.
Great! Thanks

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Title: Re: Gps for Revolution
Post by: startrek66 on September 14, 2016, 12:03:36 am
I received neo - 7m gps and the wire welds are not at all well done unfortunately .
I would like confirmation if the compass is integrated in it .
There are the six wires GND, VCC, TXD, RXD, SCL, SDA.
I see a chip L8832036 signed , could be the compass ?
Regards
Title: Re: Gps for Revolution
Post by: hwh on September 14, 2016, 01:41:44 am
Yes, that is the mag chip.  It should work fine with a revo.  Unlike the Naza ones it will take up both the main and flexi ports.  Since it doesn't have a flash memory chip it won't work with a cc3d.

The first 4 wires (gps and power) go to the main port and the last two (mag) go to the flexi port.  The wiring is in the wiki at https://librepilot.atlassian.net/wiki/display/LPDOC/GPS+setup#GPSsetup-GPSwiring and your gps is the one on the left.
Title: Re: Gps for Revolution
Post by: startrek66 on September 14, 2016, 11:11:14 pm
Ok, thank's for information.
I suppose that flash memory chip is the missing chip U2 on the board near Neo 7M?
Title: Re: Gps for Revolution
Post by: hwh on September 14, 2016, 11:15:25 pm
Yes, that's the one.  It doesn't matter unless you want to use it with a cc3d.  The revo and sparky2 normally (you can disable it) reconfigure the gps with the optimum settings for them every time they boot up.
Title: Re: Gps for Revolution
Post by: startrek66 on September 15, 2016, 08:10:31 am
For now I do not care to use it in flight , but how can I check if the GPS is working properly and receives the satellites?

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Title: Re: Gps for Revolution
Post by: Mateusz on September 15, 2016, 11:19:29 am
For now I do not care to use it in flight , but how can I check if the GPS is working properly and receives the satellites?

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In GCS you can see number of satellites and whether it gets a stable 3D lock/fix. If you're losing 3D fix, then you need to wait till it finds more sats.
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Title: Re: Gps for Revolution
Post by: startrek66 on September 15, 2016, 11:36:32 am
I can use GCS 15.09? Connect only main port?
I remove
Title: Re: Gps for Revolution
Post by: Mateusz on September 15, 2016, 11:46:57 am
I can use GCS 15.09? Connect only main port?
I remove

15.09 supports only one GPS+AuxMag unit which is OP Platinum GPSv9 (not produced anymore). It also supports Ublox protocol GPS units, but that's just GPS alone and not very useful if you indention is to use navigation.
16.09-RC1 supports external magnetometer so you can connect Ublox GPS and HMCxxxx mag, it also supports GPS+AuxMag (over I2C) and DJI GPS (unit also contains AuxMag and I recommend this one).
For 16.09-RC see https://forum.librepilot.org/index.php?topic=2266.0

To just test GPS unit alone, you can just connect main-port with 15.09 and it will show sats on Revo. Remember GPS and Mag are two different devices that both are needed for navigation, and it just happens some GPS units have Mag integrated.
Title: Re: Gps for Revolution
Post by: startrek66 on September 21, 2016, 08:33:35 pm

I can connect the cable without perform a wizard?
Title: Re: Gps for Revolution
Post by: hwh on September 21, 2016, 08:54:45 pm
Yes, just go to the config tab and set the settings for the port(s) you plug it into.
Title: Re: Gps for Revolution
Post by: startrek66 on September 21, 2016, 11:19:38 pm
Yes, just go to the config tab and set the settings for the port(s) you plug it into.
Thanks.
It's just power the revo through the USB cable from the PC or do I connect the battery lipo?
Title: Re: Gps for Revolution
Post by: hwh on September 22, 2016, 05:39:15 am
USB powers only the flight controller itself, nothing plugged into it gets powered by USB.  To power a GPS (or a receiver) you have to connect the battery.
Title: Re: Gps for Revolution
Post by: startrek66 on September 22, 2016, 08:10:28 am
Ok very well
Title: Re: Gps for Revolution
Post by: startrek66 on September 23, 2016, 08:58:21 pm
USB powers only the flight controller itself, nothing plugged into it gets powered by USB.  To power a GPS (or a receiver) you have to connect the battery.
You know if revo board ports are protect by connection with devices with defects? I'll explain. A device with defects can damage the revo?
Title: Re: Gps for Revolution
Post by: hwh on September 24, 2016, 01:27:54 am
The original project's revolution had protection on the input ports.  On the various Chinese clones the protection chips are sometimes there, sometimes not.  Even on the ones with the protection chips it's still possible to damage the revo but they make it less likely.

That said, a bad GPS is unlikely to damage the revo.  For the most part it would have to put more than 5 volts onto a revo pin and I've never seen a GPS module that had more than 5 volts on it.
Title: Re: Gps for Revolution
Post by: startrek66 on September 24, 2016, 09:35:29 am
Thank you for your answer. I had a doubt, since I had to redo the wire welding on the GPS module because the Chinese quality is not good. Anyway I did the test by connecting the GPS module to the Main port with gcs 15:09 I have verified that the GPS works. From my balcony without having openings above I have received the minimum 7 satellites to get the green light. Now these satellite locations are stored on the GPS module or revo?
Title: Re: Gps for Revolution
Post by: hwh on September 24, 2016, 05:12:02 pm
I'm glad it's working finally.   :)

The actual sat locations aren't stored anywhere, their orbits are way below geosynchronous orbit (and in weird directions) so they're constantly moving anyway.   Some GPS store the ephemeris (essentially a list of sats and orbital info for them) for a while using power from either a tiny battery or supercap on them.  That makes getting a lock the second time during a day faster since the GPS doesn't have to download the ephemeris each time.
Title: Re: Gps for Revolution
Post by: startrek66 on September 24, 2016, 07:15:46 pm
Thanks.
In fact, the GPS module is a small lithium battery. I read in the Ublox NEO-7M data sheet which is designed to receive both satellites the GPS network, but also the Russians glonass. This choice as it happens?
Title: Re: Gps for Revolution
Post by: f5soh on September 24, 2016, 10:02:39 pm
Neo7 can receive russian OR regular Gps, not both at same time if i remember.

Those settings can be adjusted using the GPSSettings uavo in UavoBrowser
Title: Re: Gps for Revolution
Post by: troll on October 08, 2016, 09:19:15 am
Hello!

I'm looking GPS for autonomous flying. After investigating I'd found this:
http://www.ebay.com/itm/Ublox-NEO-M8N-GPS-Compass-for-CC3D-Revolution-Revo-Nano-Flight-Control-BoardYYc-/222271612736?hash=item33c06ba740:g:oQcAAOSwmfhX4OLX
It seems to be with MAG inside also contain proper JST connector for Revo board.

Could you please recommend or not this module?

As I understand I should use 16.09 GCS, correct?
Title: Re: Gps for Revolution
Post by: startrek66 on October 08, 2016, 10:04:41 am
Hi , for my experience only 4 wires gps module compatible with revolution must be a Naza compatible!  Verify with seller if the module is Naza clone.
Title: Re: Gps for Revolution
Post by: hwh on October 08, 2016, 06:47:35 pm
...It seems to be with MAG inside also contain proper JST connector for Revo board.

Could you please recommend or not this module?

As I understand I should use 16.09 GCS, correct?
It would need two connectors to have a mag in it that's working.  If it does have a mag chip inside you'd have to add another cable and connector to get the mag to work.  And that would take up both the main and flexi ports.

As startrek66 said, the only ones with one cable that combines the gps and mag are the clones (and original) DJI Naza GPS.  That's the one most of us recommend.  The old OP GPS v9 (Platinum) did too but it's not made anymore.