Author Topic: Moteino and Drones (sUAS, UAV, whatever)  (Read 3702 times)

syrinxtech

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Re: Moteino and Drones (sUAS, UAV, whatever)
« Reply #15 on: November 16, 2016, 04:54:37 AM »
@TomWS, to be honest, I don't know.  I'm using the following Adafruit product:

Adafruit Ultimate GPS Breakout - 66 channel w/10 Hz updates - Version 3 - PRODUCT ID: 746

In the Technical Details section, it says this:

"DGPS/WAAS/EGNOS supported"

I'll look through the examples and the provided libraries....hopefully they will have support for this option.


TomWS

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Re: Moteino and Drones (sUAS, UAV, whatever)
« Reply #16 on: November 16, 2016, 07:48:39 AM »
@TomWS, to be honest, I don't know.  I'm using the following Adafruit product:

Adafruit Ultimate GPS Breakout - 66 channel w/10 Hz updates - Version 3 - PRODUCT ID: 746

In the Technical Details section, it says this:

"DGPS/WAAS/EGNOS supported"

I'll look through the examples and the provided libraries....hopefully they will have support for this option.
I'm familiar with the device, it's a good GPS unit and, I believe, the DGPS (including WAAS if available) is enabled by default.

Looking at your coverage photo again, it may be that all points were within 15 feet of the correct position and that's probably reasonable.  Sorry to distract you on this.

Tom

syrinxtech

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Re: Moteino and Drones (sUAS, UAV, whatever)
« Reply #17 on: November 16, 2016, 09:17:53 AM »
No, not at all distracted.  I love learning new things, and especially more about things that I thought I already knew.

In fact I've spent all morning learning NMEA sentences and how to set and query various options.  I'm learning a lot by going under the covers instead of using the Adafruit-provided libraries.

I was able to turn on DGPS and WAAS.  I'm also playing with interpreting the various ACK messages to make sure what I think is happening is really happening.

I'm gathering another set of data as we speak so I'll be able to see if turning things on helped from a variability perspective.

TomWS

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Re: Moteino and Drones (sUAS, UAV, whatever)
« Reply #18 on: November 16, 2016, 12:08:49 PM »
No, not at all distracted.  I love learning new things, and especially more about things that I thought I already knew.

In fact I've spent all morning learning NMEA sentences and how to set and query various options.  I'm learning a lot by going under the covers instead of using the Adafruit-provided libraries.

I was able to turn on DGPS and WAAS.  I'm also playing with interpreting the various ACK messages to make sure what I think is happening is really happening.

I'm gathering another set of data as we speak so I'll be able to see if turning things on helped from a variability perspective.
There is one sentence, I forget which one at the moment, that returns quality of position measurement.  I've achieved <1.0 (<2 is desirable) easily with this receiver with an external powered antenna (GPS unit was located in my house).  The main reason I use this receiver is to get a solid 1PPS signal I use for RTC calibration.

Tom

syrinxtech

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Re: Moteino and Drones (sUAS, UAV, whatever)
« Reply #19 on: November 16, 2016, 01:24:43 PM »
I think you're referring to HDOP (Horizontal Dilution of Precision).  You've got a really good signal when it's < 1.0.

I'm sitting here at my kitchen table getting 0.75.


syrinxtech

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Re: Moteino and Drones (sUAS, UAV, whatever)
« Reply #20 on: November 16, 2016, 10:10:37 PM »
Well, spent the afternoon trying out a new GPS library.  I had been using the Adafruit libraries and now I've experimented with the TinyGPS and TinyGPS++ libraries.  They offer a much simpler interface without all the bells and whistles.  I was able to get a pretty decent concentration of points with a lot less "drift".  I'm seriously thinking of switching libraries going forward but there is always more testing to do.

syrinxtech

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Re: Moteino and Drones (sUAS, UAV, whatever)
« Reply #21 on: November 18, 2016, 06:50:04 AM »
Here's a sample of 24,180 readings with no data manipulation using TinyGPS++ with a little tweaking.

syrinxtech

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Re: Moteino and Drones (sUAS, UAV, whatever)
« Reply #22 on: February 07, 2017, 10:24:04 AM »
Perhaps you could add a xenon flash lamp in case you lose it at night  :)

Cool work!

Tom

Tom,

Added two high intensity LEDs (one on each side of the board) that flash back and forth like the lights at a train stop.  Also added a buzzer that emits a very annoying sound.

Yes, one of the first things I do after initializing the GPS is enable WAAS.  It definitely makes a difference in my area.

I've used the device and driven more than 30 minutes through the country and then plotted the points using gpsvisualizer.  The plot is perfect, following every road, traffic light, etc.