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Users => Applications - Autonomous Flight => Topic started by: proctoidpaul on November 28, 2016, 04:36:53 pm

Title: Which GPS/Compass for Revo?
Post by: proctoidpaul on November 28, 2016, 04:36:53 pm
Can anyone recommend a specific GPS unit with external compass that can plug and play without modification for successful use with my Revolution board?

I've seen many units advertised that don't seem to have all the right features to work with Revo.

Thanks in advance for any tips.

Paul
Title: Re: Which GPS/Compass for Revo?
Post by: jtrout19 on November 28, 2016, 05:11:31 pm
Well that would be the original op gps unit. From what i know are not made anymore. The naza gps is fairly plug and play. You have to change connector out but thats it.
Title: Re: Which GPS/Compass for Revo?
Post by: DocHardinger on November 28, 2016, 08:40:11 pm
For me the ublox NEO M8N with mag do the job. But you need main port or Flexi-IO port for gps and flexi port for MAG. But then i got a really good position hold with mostly 17 satelites fix. And you can choose different dynamic models, useful for smoother flight in gps modes...
Title: Re: Which GPS/Compass for Revo?
Post by: proctoidpaul on November 28, 2016, 11:44:18 pm
Thanks Guys!  Please pardon my ignorance here, but other than the connector issue, do I need to worry about the fact that they are advertised for Pixhawk, Naza, etc?  For example, this one says for Pixhawk:

https://www.amazon.com/Hobbypower-NEO-M8N-Compass-Folding-Controller/dp/B00WME95LM

I'm using a full spectrum receiver, so that port is taken.  I would like to run the mini OSD if I can ever get stable enough voltage figured out, so that would only leave me one port....  I do recall reading somewhere that the receiver port can be configured to PPM + telemetry?  Would that be necessary to get all my desired features working?

The other product I found was:
https://hobbyking.com/en_us/ublox-neo-7m-gps-with-compass-and-pedestal-mount.html

.. But this is a 7M not an M8N...

If you have specific links to recommended products, that would be greatly appreciated!

Paul
Title: Re: Which GPS/Compass for Revo?
Post by: TheOtherCliff on November 29, 2016, 04:10:31 am
For GPS with mag we specifically support PixHawk (two ports), Naza (one port), OPv9 (one port).  APM (two ports) also works, but you need to set up a voltage regulator to power the mag IIRC.

IIRC 16.09 has support for re-tasking the PWM RC receiver inputs to use it with some other serial devices.  You may be able to use that for a port.
Title: Re: Which GPS/Compass for Revo?
Post by: proctoidpaul on November 29, 2016, 12:36:00 pm
For GPS with mag we specifically support PixHawk (two ports), Naza (one port), OPv9 (one port).  APM (two ports) also works, but you need to set up a voltage regulator to power the mag IIRC.

IIRC 16.09 has support for re-tasking the PWM RC receiver inputs to use it with some other serial devices.  You may be able to use that for a port.
Thanks for the clarification!


Sent from my iPad using Tapatalk
Title: Re: Which GPS/Compass for Revo?
Post by: DocHardinger on November 29, 2016, 04:46:37 pm
I bought this one

http://m.ebay.de/itm/Ublox-NEO-M8N-GPS-Built-in-Compass-Holder-for-APM-ArduPilot-Flight-Controller-/351731681219?txnId=848775120022

That works nice but is a little pricey
Title: Re: Which GPS/Compass for Revo?
Post by: proctoidpaul on November 29, 2016, 10:44:59 pm
Thanks for the link!
Title: Re: Which GPS/Compass for Revo?
Post by: tony092 on December 16, 2016, 10:23:06 am
Sorry for my question because I saw many post about GPS and I'm little bit lost. I bought a gps ublox-8m with compass but at the end it was without cable for the compass. so for this type of GPS I understand that I have to solder cable for compass that mean I will have one cable for gps using main port and one cable for compass using flex (I2C). As I would like to implement also FPV/OSD one of this port will be used for telemetry. So for GPS with compass it will remain one port of my Revo so this type of GPS with compass with two cables is not the right one. I understand that to use only one port of my Revo I have to buy NAZA GPS with compass which have one cable for both GPS + compass correct?
Title: Re: Which GPS/Compass for Revo?
Post by: Mateusz on December 16, 2016, 10:52:51 am
Sorry for my question because I saw many post about GPS and I'm little bit lost. I bought a gps ublox-8m with compass but at the end it was without cable for the compass. so for this type of GPS I understand that I have to solder cable for compass that mean I will have one cable for gps using main port and one cable for compass using flex (I2C). As I would like to implement also FPV/OSD one of this port will be used for telemetry. So for GPS with compass it will remain one port of my Revo so this type of GPS with compass with two cables is not the right one. I understand that to use only one port of my Revo I have to buy NAZA GPS with compass which have one cable for both GPS + compass correct?

There are various options for what you want to achieve
P.S Revo does not exist. It's either CC3D (Copter Control 3D) or Revolution. When chinese call it Revo they probably mean Revo, but they chain up names for easy hits with google. What they call RevoMini is another derivative that has some wired pin-out and table from the link does not apply.

Title: Re: Which GPS/Compass for Revo?
Post by: TheOtherCliff on December 16, 2016, 08:01:05 pm
You can also buy a converter that converts the PixHawk into a DJI-Naza.  That is how they make a clone DJI-Naza now days.  I would buy the authentic DJI-Naza GPS ($39 shipped).
Title: Re: Which GPS/Compass for Revo?
Post by: tony092 on December 17, 2016, 12:37:29 pm
Thanks Mateusz & TheOtherCliff for your support. Yes I think I will buy a NAZA GPS
Title: Re: Which GPS/Compass for Revo?
Post by: startrek66 on January 03, 2017, 01:15:05 am
For GPS with mag we specifically support PixHawk (two ports), Naza (one port), OPv9 (one port).  APM (two ports) also works, but you need to set up a voltage regulator to power the mag IIRC.

IIRC 16.09 has support for re-tasking the PWM RC receiver inputs to use it with some other serial devices.  You may be able to use that for a port.

I have bought this product, mark on ublox component Neo-7M-0-000, but I have not yet connected because I have to solder the jst connectors, one for gps and one for mag, total 6 wires. I want to know how recognize if will need to use a voltage regulator on mag and where to find it.
http://www.ebay.co.uk/itm/331869111579?clk_rvr_id=1148027300958&rmvSB=true&ul_ref=http%253A%252F%252Frover.ebay.com%252Frover%252F1%252F710-53481-19255-0%252F1%253Ficep_ff3%253D2%2526pub%253D5574735181%2526toolid%253D10001%2526campid%253D5336086427%2526icep_item%253D331869111579%2526ipn%253Dpsmain%2526icep_vectorid%253D229508%2526kwid%253D902099%2526mtid%253D824%2526kw%253Dlg%2526srcrot%253D710-53481-19255-0%2526rvr_id%253D1148027300958&ul_noapp=true
Title: Re: Which GPS/Compass for Revo?
Post by: TheOtherCliff on January 03, 2017, 05:10:41 am
It's PixHawk.  The mag should get power from the GPS power leads.  The mag power should not need to be connected like on APM so you will have 4 wires (-,+,TxD,RxD) going to the GPS serial connection and just two wires going to the mag I2C connection (SCL, SDA).
Title: Re: Which GPS/Compass for Revo?
Post by: startrek66 on January 03, 2017, 01:43:10 pm
Though I have heard a gps + Mag for apm should have 8 wires in total?
Title: Re: Which GPS/Compass for Revo?
Post by: TheOtherCliff on January 05, 2017, 06:54:51 am
Read previous post.  :)
Mag gets power and ground from the GPS wires.
Title: Re: Which GPS/Compass for Revo?
Post by: joani on January 07, 2017, 03:01:41 am
 Una pregunta amigo, cuando hace esos movimientos en la pantalla después de calibrar todo ?, y uno lo quiere hacer volar cuando se va para todos lados y uno con el radio trata de equilibrarlos , son los mismo movimientos que se ven en el  gcs?quiero decir que el drone no se queda quieto porque la altitud  oscila continuamente en el gsc ?si  el mismo estuviera estático como en los modos complementarios , esto no sucedería? . Yo trate  de equilibrarlos con la rotación virtual y la orientacion  del mag pero mejoro y ahora otra ves esta loco: solo que ahora si pongo estabilizado y gps asistido , no me arma motores , si lo quito si los arma
Title: Re: Which GPS/Compass for Revo?
Post by: TheOtherCliff on January 07, 2017, 09:08:40 am
Sorry.  I am having difficulty understanding the Google translation.

Also, I think you mean Attitude, not Altitude.

Small amounts of movement in the PFD (Flight Data screen) are normal.  Up to say 5 degrees of movement is OK.  PFD showing it flipping and flopping upside down is not OK.
Title: Re: Which GPS/Compass for Revo?
Post by: joani on January 07, 2017, 12:17:44 pm
okey amigo , me pasa lo mismo ejejje.no hay problemas , pues si es actitud , me equivoque.Pero sucede que yo lo había dejado bien , se acuerda? y lo tuve sin probar una semana , ahora lo quise volar y como que descalibro nuevamente y sin modificar nada .
Yo  lo tengo  en 180;90;180 ,así lo había dejado y funcionaba en gps13 siempre, pero nunca llegue a probarlos  los modos autónomos  .Los probaba como andaba un rato de noche en  mi casa es estabilizado con gps asistido , pero los sábado lo llevo a un lugar descampado-resulta que empece a tocar la orientación virtual de attitude. si estaba tirado para adelante 5 grados , le tiraba para atrás el cabeceo  5 grados, pero lo probé y no me convenció, asi que lo deje como estaba , 0;0;0 :pero ahora es como que se descompuso nuevamente
Title: Re: Which GPS/Compass for Revo?
Post by: TheOtherCliff on January 07, 2017, 06:12:03 pm
180,90,180 es una configuración muy extraña para el magnetómetro.

Si todo ("controlador de vuelo" y "GPS con mag") está montado normalmente (las flechas apuntan hacia adelante) entonces:
- Si usted tiene un GPS con I2C mag, conectado a FlexiPort (generalmente PixHawk o APM) debe utilizar 180,0,180 (o 0,180,0)
- Si usted tiene DJI o GPSv9 tipos de GPS, entonces usted debe utilizar 0,0,0

Si se configuran incorrectamente, el PFD se pondrá al revés en la página "Datos de vuelo" ("Flight Data") (una vez que ATTI y STAB pasen a verde).
Title: Re: Which GPS/Compass for Revo?
Post by: nkout on January 19, 2017, 11:16:19 am
I am also thinking of gps/mag. I am only looking sellers shipping to Greece. Among the following GPSs, which one do you suggest?

https://drotek.com/shop/en/drotek-parts/512-ublox-neo-m8-gps-hmc5983-compass.html

http://www.ebay.com/itm/Original-DJI-GPS-Module-for-Naza-M-V2-Multirotor-Autopilot-Flight-Control-/172294421532?hash=item281d8c3c1c:g:kSsAAOSwqfNXowk0

http://www.ebay.com/itm/DJI-GPS-Compass-Module-for-DJI-NAZA-M-Lite-Flight-Control-System-/251862698572?hash=item3aa42fca4c:g:hPEAAOSwofxUbb15

Is the drotek gps compatible with revo?
Is there any advantage of naza v2 compared to v1, making sense for the extra price?

Nikos
Title: Re: Which GPS/Compass for Revo?
Post by: TheOtherCliff on January 19, 2017, 12:40:16 pm
The first one is OK but it needs two ports (MainPort for GPS and FlexiPort for mag).  That means one less port when you want to do GPS and mag and OSD all at the same time.  Maybe you cannot do all at once if you use this GPS.  This GPS is a PixHawk style which LP does support.  It has the more recent Ublox Neo8 GPS inside it.  It can see many kinds of GPS type satellites, not just USA GPS satellites.  You will get more satellites if you use this.  It also seems to have a worse "jumping" problem when there are large flat things like metal roofs (even when it is outside) to reflect the signals and confuse it.  This kind of mag (I2C) sometimes (infrequently) has compatibility problems with Revo ports and needs shorter cable or external pullup resistors.

The second one is too expensive if you ask me.  :)  I have bought and tested the Naza Lite version, not this V2.  I would not get this one for price and maybe incompatibility?

The third one is also OK but be aware that this real DJI Naza brand GPS uses an older version of GPS component.  This real DJI Naza brand uses Ublox Neo6 GPS and only sees USA GPS satellites, but these orbit the whole earth, so that usually isn't a very large problem.  Maybe some Russian or Chinese users can post whether USA GPS works well for them.  I have heard complaints about USA GPS when far away from USA, but don't know if they are true.
Title: Re: Which GPS/Compass for Revo?
Post by: nkout on January 19, 2017, 12:53:52 pm
Thanks a lot for the clear answer.

I will think a little bit about it....

I already have a neo6m gps working with my revo (but never tested in flight, only at ground), so i will check if revo's internal mag can work with my setup. I have a 45cm quad. I will try to twist all power cables for less interference.

And if any issues, I will order a new gps with mag.

Thanks in any case!

Nikos
Title: Re: Which GPS/Compass for Revo?
Post by: TheOtherCliff on January 19, 2017, 12:55:35 pm
It sticks in my mind that the GPS V2 can additionally work when plugged into the V2 bluetooth hub?
Title: Re: Which GPS/Compass for Revo?
Post by: TheOtherCliff on January 19, 2017, 12:59:24 pm
Power distribution board can be a problem if it is not designed to minimize magnetic fields.  I suspect that the best ones usually are designed with + on top and - on bottom (or the other way), so that one sheet is one and the other sheet is the other.
Title: Re: Which GPS/Compass for Revo?
Post by: nkout on January 19, 2017, 01:04:02 pm
Regarding power interference to mag, can a solution be putting revo away from frame using a GPS folding mount?
Title: Re: Which GPS/Compass for Revo?
Post by: TheOtherCliff on January 19, 2017, 07:39:30 pm
Power interference is the main source of mag interference.  PDB (power distribution board) is only one place to be careful.  Of course the thick high current wires are the other main places.  I mention the PDB because you can twist wires, but the only way to fix the PDB is to buy a different brand.

Yes, you could move the Revo up much higher instead of mounting a GPS/mag up high.  I don't know of anyone that has tried it though.  Lots of longer wires to Revo are a pain, but these wires are low current and basically don't matter when compared to the high current wires.  Just make sure to keep them away from the Revo, because a careless small wire that is close to the mag sensor would have an affect since it is so close.  Once it is mounted and powered up with a flight battery, you can test it by watching mag scope in GCS while wiggling small wires (keep Revo motionless).

Also move power wires down lower where reasonable.

If Revo is mounted on a pole be careful of resonance like a plucked guitar string; motor vibration at certain RPMs can drive resonance.  Also move high current wires down as low as possible and twist them all, including battery cable.

The distance from nearest power wires to GPS/mag on my good flying F330 (2212 motors, 3s2500 lipo) quad is 18cm.  For larger motors or larger battery = more current, I would try to make it farther.

Final test is to watch GCS mag scopes while you run individual and all motors with multicopter firmly held down and motionless (must have props on).  I am going to try this with a quad by screwing it down to wooden deck today.  Maybe tying it down will be motionelss enough.
Title: Re: Which GPS/Compass for Revo?
Post by: HighAltitude on January 21, 2017, 03:45:16 pm
I've tried several options to get a reliable GPS/Mag signal. My initial strategy was to try to get by as cheaply as possible.
I twisted the power wires between the battery and the lower frame/PD board and the ESC's and motors insofar as their length allowed, mounted the Revo board on an auxiliary upper deck above the upper frame board on 25 mm spacers, and recalibrated all the sensors several times, but still couldn't get a reliable Mag signal from the onboard Mag sensor. 
I've also tried a couple of  mini OP GPS and uBLOXNEO-M8N modules, which worked OK for a GPS fix, but didn't solve the Mag problem.     
Since I have reliable PWM connections between my Orange receivers and my Revo boards, I haven't wanted to deal with trying to get a PPM connection set up to free up more Flexi-IO port connections for other uses.  This leaves only the Main and Flex port available for GPS, Mag, and OSD I/O, which precludes adding extra connections between the modules and the FC board. In addition, I'm not confident enough in my soldering skill to add connections to the M8N modules without damaging them.  Additionally, I try to minimize the rats nest of wiring that is otherwise inevitable with extra connections. 
So, I bit the bullet and bought genuine DJI NAZA GPS/Mag units for both my quads.  They weren't egregiously expensive and plug and play into the Main port after substituting 4 pin JST for the DJI connector, which was an easier soldering job than working with the teensy weensy solder pads on the circuit board.  They've calibrated easily and I now have reliable GPS flight modes.
It's been interesting and educational to try out the various options, but, in retrospect, would have been cheaper and simpler to get NAZA units from the beginning.
Title: Re: Which GPS/Compass for Revo?
Post by: vk4tec on April 04, 2017, 05:32:55 pm
Did you have to make the uBLOXNEO-M8N modules not NMEA ?

Andrew
Title: Re: Which GPS/Compass for Revo?
Post by: TheOtherCliff on April 04, 2017, 07:41:15 pm
He is using a Revo FC.  Revo does a GPS configuration automatically.