RTK gps on a budget (Quectel LC29HEA)

Thank you very much! This is definitely necessary.

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Gentlemen. Not trying to hijack the thread… I too am building a rover mower and on a budget. A newbee. I can get RTK NTRIP for free. Trying to get a list of hardware and firmware. This topic is hugely interesting and important to me. But having some trouble following the details since I’m new. Hate to ask, but could someone net it out? I take it that the LC29HEA module is the right one? I see the helix antenna as well. Would it work with the Speedybee F405 Flight Pack?

We will see if and how (complicated or easy) the LC29HEA modules can be imported into Ardupilot (including correction signals from NTRIP providers) compared to the existing u-blox F9P based systems. After integration, the performance will have to be compared with an u-blox system. As a u-blox F9P user, I am just as curious. My LC29HEA hardware is still on its way and delivery has been announced for the end of May.

Thanks in advance to @Oli1 for his support.

Rolf

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I’m hugely interested in the LC29HEA integration effort, including firmware for 5mhz. I really hope that people smarter than me can figure out how it integrates, esp with the public NTRIP data. I still don’t have a FP yet, either. Thinking of Matek H743 or Pixhawk 6C. Anyone have any opinions (I know its early) if either of these would be easier to integrate with the LC29HEA?

Neither autopilot is more difficult to integrate (unless you can’t solder). They both have adequate serial ports and identical processors.

The problem is that no one to my knowledge has successfully used this GPS to date. Watch this topic for updates.

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We have at least 4 people with orders incoming, in three or four weeks we’ll hopefully know more :slight_smile:

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Oli, what are the selections in the LC29HEA aliexpress link that you shared? The second selection is $46. The first and third are $32 and the last is $54 with antenna. Is the last option the same as the second, but with an antenna too? Its hard to sort out on aliexpress–there’s little detail.

I just checked again, and it’s no longer the second selection so I’ve deleted that part… you would want to go with the EC29HEA. HDA and HBA have only 1Hz update rate, same for HBS, plus it’s standard precision only.

Hate to be a PITN newbee, but when I just checked your link ( https://www.aliexpress.us/item/3256806517861023.html?gatewayAdapt=deu2usa4itemAdapt ), it looks like 1st option is E29HDA, 2nd is a picture and says EC29HEA, and 3rd says EC29HBS, 4th is EC29HBA with antenna. So the right option is still the second option, with the picture and label EC29HEA for $46.06? I’m doing a rover running at 3mph. Do I still need the faster 5hz rate? No chance the newest H7 flight packs can handle 10hz? Since 46 is so much better than 300 (or more), I might order it and take a risk that you all can figure out how to integrate it…

That’s not a function of the processor. 5Hz max.

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@dkemxr I think it can handle 10Hz, or at least 7Hz

The AliExpress listing is inconsistent. When I click it the EA version is the first for me when I’m logged in but the second when I’m not. In any case, EA is the right option. This:
image

I don’t know if you need 5Hz, at 3mph you would have a position update every 1.35m at 1Hz, vs every 0.27m at 5Hz. If it works at 10Hz with Ardupilot is anyone’s guess. To be fair, if it works at all is anyone’s guess as well, but we know from experience that 10Hz tends to make problems. We’ll have an answer soon enough, or so I hope.

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Wow. Thanks. That puts it in perspective. 1.35m is pretty far. .27m is much better. I’ve also found aliexpress pretty inconsistent. I appreciate the clarification. I wish all of us good luck in making it work.

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10Hz has been problematic in previous circumstances. Not sure about 7Hz, 5Hz seems to be generally stable.

For a mower (his use case) it probably makes no difference at all…

I’ve seen at least one report of 7Hz working. I remain skeptical that it’s actually useful.

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After many attempts, I managed to get the LC29Hea working.
The problem was arducopter 4.4.0. only on version 4.6.0 I managed to connect. I also noticed that there is a mistake in the module documentation, the default baud rate is 460800, not 115200.

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Awesome! Give us some details, general impressions, what GPS firmware version, update rate, RTK capabilities (if you’ve tested them…), maybe your params file, mayyybe a couple of flight logs. No pressure though :smiley:

Has anyone done a flight test with the LC29HEA? I have and having problems in Loiter mode it is not stable and moves around a lot. But Drone works fine with a Ublox M9N GPS.
here is a screen shot of Lat. & Lng. from the flight.


could use some help.
Thanks
Dennis

Post a link to the log file.

What Dave said, also what GPS firmware do you have flashed?