Difference between revisions of "Sensors/GPS"

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<categorytree style="float:right; clear:right; margin-left:1ex; border: 1px solid gray; padding: 0.7ex;" mode=pages>Sensors</categorytree>
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<div style="float:left; clear:left; margin-right:2ex; padding: 0.7ex;">__TOC__</div>
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<br style="clear:both;" />
 +
 
 +
=GPS Receivers=
 +
 
 +
An overview of GPS receivers used in combination with Paparazzi. The list is by far not complete. A lot more devices will work flawlessly with Paparazzi. If you have a GPS receiver you have used with Paparazzi that is not listed here, it would be great if you could add that information to this page.
 +
<br style="clear:both;" />
 +
 
 +
=[http://1bitsquared.com 1BitSquared] [http://1bitsquared.com/products/g0-gps G0 GPS]=
 +
 
 +
[[Image:G0_GPS_V1_1_Top_with_skirt.jpeg|240px|thumb|left|G0 GPS]]
 +
 
 +
[http://1bitsquared.com 1BitSquared] sells a Paparazzi UAV compatible GPS module called [[G0]]. It is designed to neatly fit on top of the [[Elle0]] autopilot. It can also be used with any other Paparazzi UAV compatible hardware. [[G0]] GPS module features a large ground plane with optional ground plane skirt, as well as RF shielding on the back of the module.
 +
 
 +
The large ground plane improves the directionality of the unit helping reject multi-path. When using the [[G0]] GPS unit on a multi-copter it results in less drift when taking off the ground, and improves GPS lock when flying from waypoint to waypoint.
 +
 
 +
The EMI shielding on the back of the unit decreases the amount of noise injected from the aircraft avionics into the GPS unit, improving the noise to signal ratio. An increased signal results in a more robust satellite lock, and more reliable fully autonomous and guided flight operations.
 +
 
 +
[[G0]] GPS module is using a U-Blox that is providing very fast speed updates that are crucial for accurate navigation within Paparazzi UAV. Additionally Paparazzi UAV supports the binary U-Blox protocol that is very efficient to parse compared to the very vaguely defined NMEA text protocol. Just enable the UCenter Module in your airframe file and Paparazzi will configure the module for best performance without the need for user interaction.
 +
 
 +
For more information go to the [[G0|G0 GPS wiki page]].
 +
 
 +
<br style="clear:both;" />
 +
 
 +
=[http://swiftnav.com/ Swiftnav] Piksi=
 +
 
 +
A very special receiver is the OpenSource (almost all...) Swiftnav Piksi GPS receiver. How to use this device with Paparazzi is described on the a specific page
 +
[[Image:Piksi_GPS_back.jpg|200px|thumb|left|Swiftnav Piksi]]
 +
<br style="clear:both;" />
 +
 
 +
=LS20031 GPS Receiver=
 +
 
 +
[[Image:ls20031.jpg|170px|thumb|left|LS20031]]
 +
Sparkfun sells the LS20031 GPS module which uses NMEA (Paparazzi support for NMEA is BETA right now.) This Locosys GPS module supports WAAS (U.S. DGPS), EGNOS (EU DGPS), and MSAS (Japanese DGPS).
 +
 
 +
More information on configuring the GPS via PMTK can be found [http://dallasmakerspace.org/wiki/LS20031_GPS here]
 +
<br style="clear:both;" />
 +
 
 +
=Globalsat BU 353=
 +
 
 +
[[Image:BU-353_gps_receiver.jpg|thumb|left|170px|BU-353 GPS receiver]]
 +
 
 +
USB US Globalsat GPS-Mouse
 +
 
 +
Typical Uses:
 +
 
 +
* Parrot AR Drone 2.0
 +
* Ground Station GPS (direct support with Linux / gpsd)
 +
 
 +
''Not appropriate for many airborne applications due to extra USB-serial circuitry and weight of housing and internal magnet''
 +
 
 +
Basic compatibility with Windows, Mac and Linux.<br/>
 +
More information at the [[GPS/BU_353]] site.
 +
<br style="clear:both;" />
  
 +
=uBlox=
  
==Overview==
 
 
[[Image:U-blox_color_warm_60.gif|100px]]
 
[[Image:U-blox_color_warm_60.gif|100px]]
 +
[http://www.u-blox.com uBlox is a Swiss technology company] that develops very good positioning modules. They are the recommended GPS modules for use with Paparazzi autopilots. Note that u-Blox produces the modules only. They do not sell complete boards to end users. These are sold by a multitude of vendors.
  
Paparazzi autopilots are designed around the popular [http://www.u-blox.com u-blox] brand of receivers.
+
Why uBlox:
 
+
*Low cost ([[Sensors/GPS#u-blox_NEO-6M|i.e. NEO6-M]])
*Features:
+
*Small size
**Small size
+
*Excellent performance (u-Blox 7 and 8 series)
**Excellent performance
+
*Up to 10Hz update rate
**4Hz position update rate
+
*5V tolerant UART
 +
*Works out of the box with Paparazzi's u-Blox [[Module/GPS_UBlox_UCenter|auto-configuration module]]
  
The '''[[Tiny]]''' features an onboard LEA series GPS receiver and patch antenna, while '''[[Classix]]''' and '''[[Previous_Autopilots|AVR-based]]''' boards require an external receiver+antenna such as the [[#Paparazzi_Stand-alone_GPS_Receivers|Paparazzi GPS]] or [[#u-Blox_SAM-LS_GPS_Smart_Antenna|SAM-LS]].  Please note that the receivers must be configured (prior to use with the autopilot) as indicated below. Both modules have proven reliable and robust.  
+
The '''[[Tiny]]''' series features an onboard LEA series GPS receiver and patch antenna, while most other boards boards require an external receiver+antenna such as the [[#Paparazzi_Stand-alone_GPS_Receivers|Paparazzi GPS]] or [[#u-Blox_SAM-LS_GPS_Smart_Antenna|SAM-LS]].  
  
 
{|align = center
 
{|align = center
 
|-
 
|-
 
|[[Image:Lea big.jpg|200px|thumb|center|u-blox LEA GPS Receiver]]
 
|[[Image:Lea big.jpg|200px|thumb|center|u-blox LEA GPS Receiver]]
|[[Image:Ublox_SAM-LS.jpg|200px|thumb|center|u-blox SAM-LS GPS receiver (w/built-in Smart Antenna)]]
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|[[Image:Ublox_SAM-LS.jpg|200px|thumb|center|u-Blox SAM-LS GPS receiver (w/built-in Smart Antenna)]]
 +
|[[Image:UBlox_LEA-6H_Sarantel_Helix_s.jpg|200px|thumb|center|u-Blox LEA-6H GPS receiver with Sarantel Helix Antenna]]
 
|}
 
|}
  
'''Note:''' The proprietary UBX protocol is used as it offers more information and efficiency than the universal NMEA protocol. The protocol is parsed in <tt>sw/airborne/gps_ubx.c</tt>. Other GPS brands would require a similar parsing file to be written for NMEA or other proprietary protocols.   
+
'''Note:''' The proprietary UBX protocol is used as it offers more information and efficiency than the universal NMEA protocol. For details take a look at the code in <tt>sw/airborne/subsystems/gps/gps_ubx.c</tt>.
  
==GPS Receivers==
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==u-Blox LEA Series Receivers==
  
===u-Blox LEA Series Receivers===
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<!-- [[Image:Lea big.jpg|200px|thumb|right|u-blox LEA]] -->
[[Image:Lea big.jpg|100px|thumb|right|u-blox LEA]]
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[[Image:Lea5htiny13.jpg|thumb|left|200px|LEA-5H installed on the Tiny]]
The '''[TWOG_v1|TWOG]''', '''[[Classix]]''' and '''[[Previous_Autopilots|AVR-based]]''' boards require an external GPS module and antenna.  The '''[[Tiny]]''' features an integrated receiver and antenna.  Either type is designed for [http://www.u-blox.com/ u-blox] 4 and 5 series GPS receivers and the proprietary UBX binary protocol.  An external battery or capacitor is typically used to enable the GPS to retain data while powered off for significantly faster signal re-aquisition.  Any of the LEA-4 and LEA-5 series receivers can be used including the less expensive LEA-4A, 4S, 5A and 5S models as the special boot configuration code required for these models is already written.
+
The '''[[Lisa]]''' series, '''[[Twog_v1|TWOG]]''', '''[[Classix]]''' and '''[[Previous_Autopilots|AVR-based]]''' boards require an external GPS module and antenna.  The '''[[Tiny]]''' features an integrated receiver and antenna.  Either type is designed for [http://www.u-blox.com/ u-blox] 4, 5 and 6 series GPS receivers and the proprietary UBX binary protocol.  An external battery or capacitor is typically used to enable the GPS to retain data while powered off for significantly faster signal re-acquisition.  Any of the LEA-4, LEA-5 and LEA-6 series receivers can be used including the less expensive LEA-4A, 4S, 5A and 5S and similar low cost 6-series models as the special boot configuration code required for these models is already written as a [[Module/GPS_UBlox_UCenter|module]].
 +
 
 +
<source lang="xml">
 +
  <!-- autobaud - runtime configuration of - ROM-only modules: use ucenter-module to configure your UBlox with no cable nor windows u-center -->
 +
  <load name="gps_ubx_ucenter.xml" />
 +
</source>
  
 
*4Hz Position update rate
 
*4Hz Position update rate
 
*Supports active or passive antennas
 
*Supports active or passive antennas
 
*Supports [http://en.wikipedia.org/wiki/DGPS DGPS], [http://en.wikipedia.org/wiki/WAAS WAAS], [http://en.wikipedia.org/wiki/EGNOS EGNOS], and [http://en.wikipedia.org/wiki/MSAS MSAS]
 
*Supports [http://en.wikipedia.org/wiki/DGPS DGPS], [http://en.wikipedia.org/wiki/WAAS WAAS], [http://en.wikipedia.org/wiki/EGNOS EGNOS], and [http://en.wikipedia.org/wiki/MSAS MSAS]
*Low position [http://paparazzi.enac.fr/wiki_images/Gps_rx_noise.pdf noise] figure
+
*Low position noise figure
[[Image:TINY_1.3_MCU_BOTTOM.JPG|thumb|center|250px|LEA-4P installed on the Tiny]]
+
 
 
<br style="clear:both">
 
<br style="clear:both">
  
===Paparazzi Stand-alone GPS Receivers===
+
==Paparazzi Stand-alone uBlox GPS Receivers==
[[Image:Ppzgps13_800.jpg|100px|thumb|left|Paparazzi GPS13]]
+
 
[[Image:LEA5HExternalModulePinout.jpg|250px|thumb|right|LEA-5H Full Board Pinout]]
+
<gallery>
There are currently two (LEA-based) stand-alone, GPS receiver + antenna, prototype boards in development; the first one is based on the Sangshin 13mm patch antenna.<br>
+
Image:Ppzgps13med01.jpg|Top
The second is based on the Sarantel helix antenna.  Drawings for both are available from the [http://cvs.savannah.gnu.org/viewcvs/paparazzi/paparazzi3/hw/ CVS]
+
Image:Ppzgps13_lrg_02.jpg|Bottom
Version 1 (V1) BOM is here.. Please post any pics you might have and check this for accuracy<br>
+
</gallery>
 +
<p>Paparazzi source provides a design for an external GPS board. An external GPS board is required for other boards like Lisa, TWOG, Elle0 and Classix.
 +
Programming it is similar to the Tiny2.11 GPS configuration. If you build your own you will want to upload the latest u-blox firmware before you configure. See [[Get Hardware]] for sources of assembled boards.</p>
 +
<p>
 +
The Paparazzi design in https://github.com/paparazzi/paparazzi-hardware/tree/master/sensors/gps/gps_13. The board is very small and light as it has only the components required. It is powered from the 5v line on the "downloads" connector of a TWOG. Also note it is a 4-layer PCB that means better noise resistance. The board has pins for USB connection but requires a different cable and a solder jumper to be move from the ground (default) to 3.3v input to enable the USB port on the module.  
 +
</p>
 +
<p>
 
[http://paparazzi.enac.fr/wiki_images/Gps_13_BOM.xls V1 BOM.xls]<br>
 
[http://paparazzi.enac.fr/wiki_images/Gps_13_BOM.xls V1 BOM.xls]<br>
 
[http://paparazzi.enac.fr/wiki_images/TinygpsBOM.txt Eagle Parts List Output.txt]<br>
 
[http://paparazzi.enac.fr/wiki_images/TinygpsBOM.txt Eagle Parts List Output.txt]<br>
 +
See [[Get_Hardware|Get Hardware]] page for suppliers.
 +
</p>
 +
 +
===Wiring Diagram===
 +
 +
{|align = none
 +
|-
 +
|[[Image:TWOG to GPS.jpg|200px|thumb|center|TWOG to Standalone GPS Cable Schematic]]
 +
|[[Image:gps13v09FTDIcable.jpg|200px|thumb|center|GPS13 v0.9 Ucenter cable (ftdi)]]
 +
|[[Image:booz gps.jpg|200px|thumb|center|BoozGPS (quadrotor gps V1.1 2009/5) Ucenter cable (ftdi)]]
 +
|}
 +
 +
===uBlox to ARdrone 2===
 +
 +
[[Image:HowtoConnectUSBHelixGPSForParrotARDrone2.jpg|thumb|left|How to connect USB to uBlox Helix GPS for Parrot ARDrone2]]
 +
To connect a uBlox with Helix antenna via a USB to serial cable that you can just plug into your ARdrone 2
 +
<br style="clear:both;" />
  
If this needs fixing don't be shy, fix away.
+
==3rd Party u-blox Reference Design Boards==
 +
 
 +
<p>
 +
[[Image:LEA5HExternalModulePinout.jpg|thumb|left|LEA-5H Full Board Pinout]]
 +
The only other GPS board in use seems to be u-blox reference designs or similar to it. They have LEA-4H, LEA-5H and LEA-6H (typically) and several interfaces. Often a larger antenna as well.
 +
</p>
 +
<p>
 +
The board in the photo is a [http://www.rfdesign.co.za/pages/5645456/Products/GPS-Products/Receiver-Boards.asp RF DESIGN] LEA-5H-SMART.
 +
</p>
 +
<p>
 +
The jumpers adjacent to the TTL interface connectors need to be closed with low value resistors for paparazzi uart port use. Also a [http://nz.element14.com/jsp/search/productdetail.jsp?SKU=1514218 battery] has to be added with an appropriate charging resistor to enable RTC functionality.
 +
</p>   
  
 
<br style="clear:both;" />
 
<br style="clear:both;" />
  
===NAVILOCK NL-507ETTL===
+
==NAVILOCK NL-507ETTL==
 +
 
 
[[Image:Navilock NL-507ETTL.jpg|thumb|left|NAVILOCK NL-507TTL]]
 
[[Image:Navilock NL-507ETTL.jpg|thumb|left|NAVILOCK NL-507TTL]]
 
The NAVILOCK NL-507TTL u-blox TTL Modul 60416 features an LEA-4 series receiver and 25mm patch antenna on a 30mm x 30mm board.
 
The NAVILOCK NL-507TTL u-blox TTL Modul 60416 features an LEA-4 series receiver and 25mm patch antenna on a 30mm x 30mm board.
Line 58: Line 153:
 
<br style="clear:both;" />
 
<br style="clear:both;" />
  
===SPK GS406===
+
==SPK GS407==
[[Image:GS406.jpg|thumb|left|SPK GS406 with LEA-5]]
+
 
[http://www.sparkfun.com/commerce/product_info.php?products_id=8889 Sparkfun] sells a nice small module featuring the newer 5-series receiver and the highly rated Sarantel antenna for about $90The design is based around the active version of the Sarantel instead of the more appropriate passive model and there's some potentially tricky soldering involved to get around the ribbon cable but the price is great for this hardware.
+
[[Image:GS407.jpg|thumb|left|SPK GS407]]
<br style="clear:both;" />
+
[https://www.sparkfun.com/products/11466 This] is the model Sparkfun recommends as a replacement for the old GS406.  It's essentially the same, but uses the newer 6-series receiver, and is not using a ribbon cable as an interfaceIt  uses [http://www.sarantel.com/products/sl1206 Sarantels] SL1206 active antenna.
 +
It's recommended to buy [https://www.sparkfun.com/products/574 This extension cable] to use with it.
 +
<br style="clear:both;"/>
 +
 
 +
==u-blox NEO-6M==
  
 +
[[Image:Hk neo gps.jpg|thumb|left|Hobbyking NEO 6M back]]
 +
This is the cheapest GPS module with antenna for ~13€ at [http://www.hobbyking.com/hobbyking/store/__31135__NEO_6M_GPS_Module.html Hobbyking].
  
===u-Blox C04-5H Reference Design===
+
They come with different (sized) patch antenna, mounted on a separate PCB. The main PCB and antenna PCB are fixed with hot glue together and can be separated by hand.
[[Image:abavimage.jpg|100px|thumb|left|u-blox C04-5H]]
+
<br style="clear:both;"/>
u-Blox sells a complete module with antenna for around $200 and will also provide complete schematics, BOM, and PCB files for free if you wish to make your own.  Two versions are offered, one with an 18mm patch antenna and the other with the Sarantel P2 helical antenna.
 
See [http://www.u-blox.com/products/c04_5h.html http://www.u-blox.com/products/c04_5h.html] for more info.
 
<br style="clear:both;" />
 
  
====Connecting external receivers to Classix, 1.2.1, Lite, and RoboStix boards====
+
==Navilock NL-652ETTL==
  
The u-blox receivers require 3.3v power and all current models have 5V tolerant data lines. The best way to connect to the SAM-LS is to remove the bottom case and solder the 4 wires directly to the TIM-LL module (GND (pin 1) ,VCC (pin 2),TX (Pin 5),RX (pin 4)) check the TIM-LL datasheet for pinout diagrams.[http://www.u-blox.com/products/Data_Sheets/TIM-LL_Data_Sheet(GPS.G3-MS3-04035).pdf] The Classix and Lite boards feature a 3.3V regulator to power the GPS.
+
Nice module with u-blox 6 chip and without the annoying cable that the HK NEO-6m has.
To open the casing on a SAM-LS, remove the bottom of the casing by pulling gently, then work around popping off the solder joints (they are fairly weak) by pressing a small screwdriver against each tab in turn until it pops off.  You should then be able to access the GPS chip directly.
+
[http://www.navilock.de/produkte/G_61846/merkmale.html?setLanguage=en Navilock NL-652ETTL]
  
 +
==u-Blox C04-6H Reference Design==
  
===Sourcing from u-blox===
+
[[Image:abavimage.jpg|thumb|left|u-blox C04-5H]]
 +
u-Blox sells a complete module with antenna for around $200 and will also provide complete schematics, BOM, and PCB files for free if you wish to make your own.  Two versions are offered, one with an 18mm patch antenna and the other with the Sarantel P2 helical antenna.
 +
See [http://www.ublox.com/en/evaluation-tools-a-software/reference-designs/for-gps-chips/c04-6h.html http://www.ublox.com/en/evaluation-tools-a-software/reference-designs/for-gps-chips/c04-6h.html] for more info.
 +
<br style="clear:both;" />
  
u-blox keeps tight control over the distribution of their products.  They must be obtained DIRECTLY from their own reseller offices.  These offices may not be available in your area, for example Canada does not have a reseller.  Sample quantities can be obtained from uBlox but overnight or 2 day shipping is required which drives the cost up considerably.  While it is a large hassle obtaining these devices, it is undoubtedly worth it.
+
==Drotek Boards==
 +
[http://www.drotek.com Drotek's] u-Blox GPS boards work well and are not expensive.  
  
Talking with ublox sale for two years, Confirmed, that Order is possiable Directly from ublox, by knowing what project it was for & how was it to be use.  After long reply waiting time, the answer was: - YES,  but at least 2K-3K in volume, otherwise they're not interested.  Like to share the order ?  It is 500pcs/Roll.
+
==uBlox GPS configuration==
  
===Other potential source of u-blox GPS===
+
===Using uBlox U-Center===
  
There seems to be a few alternative source of u-blox GPS out there. They are considerably cheaper then the samples u-blox offers (at least in america). We didn't buy from these sources yet. Do not take this as a recommandation, we do not know the level of service they offer, etc.
+
''Note: Before attempting manual configuration consider adding the [[Module/GPS_UBlox_UCenter|u-blox UCenter module]] to your airframe instead. If automatic configuration does not work for you please make an issue in he gitgub issue tracker or report it to the mailing list or the Gitter chat and may attempt the manual procedure below. But be aware that a wrong configuration can cause Paparazzi not acquiring any GPS lock for sometimes hard to find reasons.'' 
  
If you do order from any of them, please update this page with your feedback.
+
[[Image:Ucenter_on_linux_using_wine_v2.png|thumb|u-center configuration software]]
 +
[https://www.u-blox.com/en/product/u-center-windows U-Center] is an application intended for the configuration of u-Blox receivers.
 +
* [https://www.u-blox.com/sites/default/files/u-centersetup_v8.27.zip Download u-center directly]
  
Here's a few link worth exploring:
+
TIP: If you want to direct access to the GPS module without unplugging from your autopilot board you can [[tunnel|upload the UART tunnel firmware]] to your AP board.
*http://www.rfdesign.co.za/pages/5645456/Products/GPS-Products/Antaris-4-Modules.asp
 
*http://www.comet.srl.ro/shop/info.html?ID=6195 ( Link error )
 
*http://www.expedienttech.com/product.htm  ( Singapore )
 
*Halfbase removed by CheBuzz due to claims of fraud and non-response from the owner
 
  
==GPS configuration using U-Center==
+
====Installation on Linux====
  
[[Image:U-center_screencap.jpg|thumb|u-center configuration software]]
+
Using the latest u-Center v8.27 is needed if you want to setup the uBlox GNSS receivers of the 8 series and use all setting available. We could use u-Center perfectly with Ubuntu 16.04 and the latest version of Wine v2.0.2.
[http://www.u-blox.com/products/u_center.html U-Center] is a very comprehensive freeware program intended for the configuration and evaluation of u-blox receivers.  
 
* [http://www.u-blox.com/products/u_center.html Download u-center]
 
  
* Note: You must [[Compiling#USB_flashing|install the UART tunnel]] to enable direct access to the built-in GPS on the [[Tiny|Tiny]].
+
Cut and paste this one-liner in you terminal to install just that:
* Note: You can run u-center on Linux by installing "wine" ([http://www.winehq.org/site/download-deb Installation of Wine]) and setting up com1 as /dev/ttyUSB0 See Info on wine for "dosdevices" setup. Just download the u-setup.exe and run it with wine, follow prompts. This has been tested with Ubuntu7.10 and Ubuntu 8.04 so far.
 
* Note: You will need a driver for your FTDI cable if you run u-center on Windows, which can be found  [http://www.ftdichip.com/Drivers/D2XX.htm here].
 
The u-blox and Tiny UARTs both operate at 3.3V TTL levels and are 5V TTL tolerant.  You must use a level shifter such as the common MAX232 to connect these devices to a standard PC serial port.  The easiest and most recommended method is to connect to a USB port instead of serial with the $20 [http://www.ftdichip.com/Products/EvaluationKits/TTL-232R.htm FTDI USB-TTL converter cable] available from Digikey, Mouser, or direct from FTDI.  Other similar converters are available from [http://www.pololu.com/products/pololu/0391/ pololu] / [http://www.sparkfun.com/commerce/product_info.php?products_id=199 sparkfun].  A stand-alone GPS such as the SAM-LS will require clean 3.3V/50mA power and a common ground with the TTL converter.
 
  
* U-blox occasionally releases firmware updates. Log on to the u-blox website using ''paparazzi'' for username & password to view or download the latest firmware imagesThere have 'never' been any updates released for the Antaris-4 series used in the Tiny.
+
<nowiki>
 +
sudo dpkg --add-architecture i386 && \
 +
  sudo apt-add-repository 'https://dl.winehq.org/wine-builds/ubuntu/' && \
 +
wget https://dl.winehq.org/wine-builds/Release.key && \
 +
sudo apt-key add Release.key && \
 +
sudo apt update && \
 +
sudo apt install winehq-stable
 +
mkdir -p ~/.wine/dosdevices &&\
 +
ln -s /dev/ttyUSB0 ~/.wine/dosdevices/COM1 && \
 +
ln -s /dev/ttyUSB0 ~/.wine/dosdevices/com1 && \
 +
ln -s /dev/ttyUSB1 ~/.wine/dosdevices/COM2 && \
 +
ln -s /dev/ttyUSB1 ~/.wine/dosdevices/com2
 +
  </nowiki>
 +
NOTE
 +
''Depending on your connection method and your udev configuration your serial device may have a different path. Just look it up using <code>dmesg</code> or <code>tail -f /var/log/syslog</code> after plugging in.''
  
Start U-center and choose your com port from the pull down list under the connect button near the top left corner of the window. Choose your baudrate from the pull down box to the right of the connect button or select the auto-baud button to the right of that. U-blox default is 9600 baud.  This must be changed to 19200 or higher to accomodate the 4Hz update rate.
+
Start U-center and choose your com port from the pull down list under the connect button near the top left corner of the window. Choose your baudrate from the pull down box to the right of the connect button or select the auto-baud button to the right of that. U-blox default is 9600 baud.  This must be set to 57600 or higher to accommodate a 10Hz update rate. It needs to match whatever your module is configured with.
<br>[[Image:U-center_buttons.jpg|connect, baud, and autobaud buttons]]
+
<br>[[Image:Ucenter_choose_baudrate.png|connect, baud, and autobaud buttons]]
 
<br style="clear:both">
 
<br style="clear:both">
  
 
===Uploading the Configuration File===
 
===Uploading the Configuration File===
 +
 
Download the appropriate configuration file below and use u-center to load in onto your receiver. Under the ''Tools'' menu, choose ''GPS configuration''.  Be sure the box 'Store configuration into BBR/Flash' is checked and hit the button ''File>>GPS''.  A few errors and retries are normal, but a significant number of errors may indicate a poor connection and the software will notify you if it is unable to send all the data successfully.
 
Download the appropriate configuration file below and use u-center to load in onto your receiver. Under the ''Tools'' menu, choose ''GPS configuration''.  Be sure the box 'Store configuration into BBR/Flash' is checked and hit the button ''File>>GPS''.  A few errors and retries are normal, but a significant number of errors may indicate a poor connection and the software will notify you if it is unable to send all the data successfully.
 
* [[Media:Tiny_LEA-4P-v6.zip|LEA-4P]]
 
* [[Media:Tiny_LEA-4P-v6.zip|LEA-4P]]
 
* [[Media:Tim-LL-V5.zip|TIM-LL]]
 
* [[Media:Tim-LL-V5.zip|TIM-LL]]
* [http://paparazzi.enac.fr/wiki_images/Tiny_LEA-5H-v5.zip LEA-5H (For Use w/ Firmware V5 ONLY!)]
+
* [[Media:Tiny_LEA-5H-v5.zip|LEA-5H (For Use w/ Firmware V5 ONLY!)]]
 +
* [[Media:Hk_NEO-6M.zip‎| Hobbyking NEO-6M]] [http://www.hobbyking.com/hobbyking/store/__31135__neo_6m_gps_module.html this module]
 +
* [[Media:Drotek_NEO_M8_38400.txt.zip |Drotek NEO-M8 at Baud 38400]]
 +
 
 +
===Automatic Configuration at Startup===
 +
 
 +
You can also use the [[Module/GPS_UBlox_UCenter|u-blox UCenter module]] which will take over the task of initializing the GPS for you when you power your autopilot.
  
 
===Manual Configuration===
 
===Manual Configuration===
 +
 
If you prefer to setup your receiver manually or have a model not listed above, here are instructions to configure your receiver in u-center.
 
If you prefer to setup your receiver manually or have a model not listed above, here are instructions to configure your receiver in u-center.
 
Open the message window (menu View->messages view) to start the configuration process by changing the following settings:
 
Open the message window (menu View->messages view) to start the configuration process by changing the following settings:
Line 123: Line 241:
 
====LEA-4P====
 
====LEA-4P====
  
1. Right Click on the '''NMEA''' Icon and choose '''disable child'''
+
# Right Click on the '''NMEA''' Icon and choose '''disable child'''
2. Choose UBX->CFG->NAV2(Navigation 2) - set it to use '''Airborne 4G''' (tells the Kalman filter to expect significant changes in direction)
+
# Choose UBX->CFG->NAV2(Navigation 2) - set it to use '''Airborne 4G''' (tells the Kalman filter to expect significant changes in direction)
3. UBX->CFG->PRT - set '''USART1''' to '''38400bps''' (must match the value in your [[Airframe_Configuration#Hardware_definitions_-_Makefile|Airframe file]])
+
# UBX->CFG->PRT - set '''USART1''' to '''38400bps''' (must match the value in your [[Airframe_Configuration#GPS|Airframe file]])
4. Change the baudrate of U-Center to 38400bps if the connection is lost at this point
+
# Change the baudrate of U-Center to 38400bps if the connection is lost at this point
5. UBX->CFG->RXM(Receiver Manager) - change '''GPS Mode''' to '''3 - Auto''' (Enabling faster bootup only if signal levels are very good)
+
# UBX->CFG->RXM(Receiver Manager) - change '''GPS Mode''' to '''3 - Auto''' (Enabling faster bootup only if signal levels are very good)
6. UBX->CFG->RATE(Rates) - change the '''Measurement Period''' to '''250ms''' (4 Hz position updates)
+
# UBX->CFG->RATE(Rates) - change the '''Measurement Period''' to '''250ms''' (4 Hz position updates)
7. UBX->CFG->SBAS : '''Disable''' (SBAS appears to cause occasional severe altitude calcuation errors)
+
# UBX->CFG->SBAS : '''Disable''' (SBAS appears to cause occasional severe altitude calcuation errors)
8. UBX->NAV (not UBX->CFG->NAV): double click on '''POSUTM, SOL, STATUS, SVINFO, VELNED.''' They should change from grey to black
+
# UBX->NAV (not UBX->CFG->NAV): double click on '''POSUTM, SOL, STATUS, SVINFO, VELNED.''' They should change from grey to black
9. UBX->CFG->CFG : '''save current config''', click '''"send"''' in the lower left corner to permanently save these settings to the receiver  
+
# UBX->CFG->CFG : '''save current config''', click '''"send"''' in the lower left corner to permanently save these settings to the receiver  
  
 
====LEA-5H====
 
====LEA-5H====
  
1. Right Click on the '''NMEA''' Text on top of the tree and choose '''disable child messages'''
+
# Right Click on the '''NMEA''' Text on top of the tree and choose '''disable child messages'''
2. Choose UBX->CFG->NAV5(Navigation 5) - set it to use '''Airborne 8 <4G'''. This tells the Kalman filter to expect significant changes in direction.  
+
# Choose UBX->CFG->NAV5(Navigation 5) - set it to use '''Airborne 8 <4G'''. This tells the Kalman filter to expect significant changes in direction. <p>    Note that this setting is only good for faster moving airplanes. For a fixed position hovering heli, 'pedestrian' setting is better</p>
    Note that this setting is only good for faster moving airplanes. For a fixed position hovering heli, 'pedestrian' setting is better
+
# UBX->CFG->PRT - set '''USART1''' to '''38400bps''' (must match the value in your [[Airframe_Configuration#GPS|Airframe file]])
3. UBX->CFG->PRT - set '''USART1''' to '''38400bps''' (must match the value in your [[Airframe_Configuration#Hardware_definitions_-_Makefile|Airframe file]])
+
# Change the baudrate of U-Center to 38400bps if the connection is lost at this point
4. Change the baudrate of U-Center to 38400bps if the connection is lost at this point
+
# UBX->CFG->RATE(Rates) - change the '''Measurement Period''' to '''250ms''' This gives a 4 Hz position update since 4 x 250ms is one second.
5. UBX->CFG->RATE(Rates) - change the '''Measurement Period''' to '''250ms''' This gives a 4 Hz position update since 4 x 250ms is one second.
+
# UBX->CFG->SBAS : '''Disable''' (SBAS appears to cause occasional severe altitude calculation errors)
6. UBX->CFG->SBAS : '''Disable''' (SBAS appears to cause occasional severe altitude calcuation errors)
+
# UBX->NAV (not UBX->CFG->NAV): double click on '''POSLLH, SOL, STATUS, SVINFO, VELNED.''' They should change from grey to black
7. UBX->NAV (not UBX->CFG->NAV): double click on '''POSLLH, SOL, STATUS, SVINFO, VELNED.''' They should change from grey to black
+
# UBX->CFG->CFG : '''save current config''', click '''"send"''' in the lower left corner to permanently save these settings to the receiver
(add the flag -DGPS_USE_LATLONG in your [[Airframe_Configuration#Hardware_definitions_-_Makefile|Airframe file]]) also make sure you set tiny_2_1_1.h if you have the latest boards Tiny/TinyWOG)
 
8. UBX->CFG->CFG : '''save current config''', click '''"send"''' in the lower left corner to permanently save these settings to the receiver  
 
  
 
* Cycle the power and verify that the new configuration was saved
 
* Cycle the power and verify that the new configuration was saved
 
* To reset the receiver to the factory defaults go to ''UBX->CFG->CFG'', select 'Revert to default configuration', and click ''Send'' at the bottom left corner.  To permanently save these values choose 'Save current configuration' and click ''Send''.
 
* To reset the receiver to the factory defaults go to ''UBX->CFG->CFG'', select 'Revert to default configuration', and click ''Send'' at the bottom left corner.  To permanently save these values choose 'Save current configuration' and click ''Send''.
 
* To backup the configuration to a file on your PC: under the tools menu, choose GPS configuration, then click GPS>>file.  This file can be re-loaded in a similar manner to configure additional identical receivers.  Be sure the box 'Store configuration into BBR/Flash' is checked when reloading a configuration file to make the changes permanent.
 
* To backup the configuration to a file on your PC: under the tools menu, choose GPS configuration, then click GPS>>file.  This file can be re-loaded in a similar manner to configure additional identical receivers.  Be sure the box 'Store configuration into BBR/Flash' is checked when reloading a configuration file to make the changes permanent.
* To update the firmware on a LEA-5H get u-center >= 5.03, revert the GPS receiver to the default configuration, get an appropriate image from u-blox (fitting your receivers serial number), find the flash identification flash.txt file in the u-center install directory and be prepared to wait a long time.
+
* To update the firmware on a LEA-5H get u-center >= 5.03, revert the GPS receiver to the default configuration, get an appropriate image from u-Blox (fitting your receivers serial number), find the flash identification flash.txt file in the u-center install directory and be prepared to wait a long time.
  
 
#NOTE: If you have a Tiny with LEA-5H module you must use u-center and manually setup the parameters as shown above (at least switch to 38400 baud manually before transferring the configuration file).
 
#NOTE: If you have a Tiny with LEA-5H module you must use u-center and manually setup the parameters as shown above (at least switch to 38400 baud manually before transferring the configuration file).
#NOTE: POSUTM is not available on LEA-5H. Instead, use POSLLH. Additionally, add the flag -DGPS_USE_LATLONG in the makefile section of the airframe xml file.
+
#NOTE: POSUTM is not available on LEA-5H. Instead, use POSLLH.
  
===Reset to Default Settings===
+
====LEA-6H====
The GPS module can be reset to its original default settings by pulling BOOT_INT high(3.3V) during a power cycle ([http://www.u-blox.com/customersupport/gps.g4/ANTARIS4_Modules_SIM(GPS.G4-MS4-05007).pdf Antaris Manual, p. 122]). It may be required after a wrong firmware upgrade or a bad configuration change.
 
  
===DGPS (Differential GPS)===
+
We use the same configuration as for version 5
Differential GPS is any method of improving GPS accuracy by comparing the GPS-indicated position of a nearby location to the known value and transmitting any error to the mobile unit.  DGPS was originally created as a means of bypassing the deliberately introduced inaccuracies in civilian GPS signals.  The original method used low frequency ground radios to relay correction data to the mobile unit and is still used today at airports, shipping ports, and even individual farms.  Satellite Based Augmentation System (SBAS) is a modern form of DGPS where the ground stations relay correction data to a GEO-Stationary satellite, which then relays it to the mobile unit on standard GPS frequencies eliminating the need for a separate radio reciever.  SBAS is currently available in 3 regions, [http://www.environmental-studies.de/Precision_Farming/EGNOS_WAAS__E/3E.html WAAS, EGNOS, and MSAS] though only WAAS is officially operational.  U-blox receivers support all common varieties of DGPS [http://www.u-blox.com/customersupport/gps.g3/ENGOS_Issues(GPS.G3-CS-04009).pdf read the u-blox SBAS application note].
 
* It is important to note that DGPS methods only improve the ''accuracy'' of the position calculation, not the ''precision''.  Since Paparazzi navigation is typically performed relative to the power-on location, any static error that could be corrected with DGPS is irrelevant.
 
  
====WAAS issues====
+
# Right Click on the '''NMEA''' Text on top of the tree and choose '''disable child messages'''
WAAS has been officially operational and "suitable for safety-of-life applications" since 2003. The default setting of all u-blox receivers ignores WAAS correction data and only uses the WAAS satellites for regular navigation like any other satellite. U-blox recommends further limiting this setting to exclude any stray EGNOS/MSAS satellites in North America, and completely disabling all SBAS functions for use outside North America.  In 2006 one formerly reliable Paparazzi aircraft began having great GPS problems and displaying very erratic altitude calculations, disabling WAAS immediately resolved the issue and this phenomenon was recreated several times for verification. Turns out a new WAAS satellite was being added to the system and the others were being moved that week for better distribution. Our advice is to completely disable WAAS.
+
# Choose UBX->CFG->NAV5(Navigation 5) - set it to use '''Airborne 8 <4G'''. This tells the Kalman filter to expect significant changes in direction. <p> Note that this setting is only good for faster moving airplanes. For a fixed position hovering heli, 'pedestrian' setting is better </p>
 +
# UBX->CFG->PRT - set '''USART1''' to '''38400bps''' (must match the value in your [[Airframe_Configuration#GPS|Airframe file]])
 +
# Change the baudrate of U-Center to 38400bps if the connection is lost at this point
 +
# UBX->CFG->RATE(Rates) - change the '''Measurement Period''' to '''250ms''' This gives a 4 Hz position update since 4 x 250ms is one second.
 +
# UBX->CFG->SBAS : '''Disable''' (SBAS appears to cause occasional severe altitude calculation errors)
 +
# UBX->NAV (not UBX->CFG->NAV): double click on '''POSLLH, SOL, STATUS, SVINFO, VELNED.''' They should change from grey to black
 +
# UBX->CFG->CFG : '''save current config''', click '''"send"''' in the lower left corner to permanently save these settings to the receiver.<p>    Make sure you activate '''"2 - I2C-EEPROM"''' if using a ROM-based NEO chipset with external EEPROM (like [http://www.hobbyking.com/hobbyking/store/__31135__neo_6m_gps_module.html HK 31135])</p>
  
====EGNOS issues====
+
* Cycle the power and verify that the new configuration was saved
EGNOS is officially in "testing mode" and no claims of reliability are madeThe [http://www.u-blox.com/customersupport/faq_antaris u-blox FAQ] states the following:
+
* To reset the receiver to the factory defaults go to ''UBX->CFG->CFG'', select 'Revert to default configuration', and click ''Send'' at the bottom left cornerTo permanently save these values choose 'Save current configuration' and click ''Send''.
* "Do you see issues with EGNOS?"
+
* To backup the configuration to a file on your PC: under the tools menu, choose GPS configuration, then click GPS>>file. This file can be re-loaded in a similar manner to configure additional identical receivers. Be sure the box 'Store configuration into BBR/Flash' is checked when reloading a configuration file to make the changes permanent.
*:"Yes. Although the data transmitted by the EGNOS satellites are usually good and valuable (e.g. during the solar storms in autumn 2003), they can sometimes be very unreliable, for example when system tests are performed. As an example, u-blox has noticed erroneous range information (up to three hundred kilometers) on various EGNOS satellite over the last few months [2006]."
+
* To update the firmware on a LEA-6H get u-center >= 6.21, revert the GPS receiver to the default configuration, get an appropriate firmaware file from u-Blox, find the flash identification flash.txt file in the u-center install directory and be prepared to wait a long time.(seriously)
  
===Further Reading===
+
====NEO-M8====
  
The u-blox [http://www.u-blox.com/customersupport/antaris4_doc.html System Integration Manual] covers a lot of GPS theory as well as product specific topics.
+
* UBX - CFG - PRT: disable NMEA output (only UBX protocol)
 +
{|align = center
 +
|-
 +
[[Image:u-center-prt.png|thumb|left|U-Center-PRT]]
 +
|}
 +
<br style="clear:both;" />
  
== Antenna options for the Tiny and Paparazzi GPS units ==
+
* UBX - CFG - MSG: activate PVT, SOL, SVINFO messages for UART1
 +
{|align = center
 +
|-
 +
[[Image:u-center-msg.png|thumb|left|U-Center-MSG]]
 +
|}
 +
<br style="clear:both;" />
  
The '''[[Tiny|Tiny 1.1]]''' features a 28mm square ground plane intended to be centered below the [[#Sangshin_13mm_Patch|Sangshin 13mm patch antenna]].  Much better performance has been seen with the 18mm antennas and an augmented ground plane.  The ground plane is a critical part of the antenna affecting not only the gain and polarization characteristics but also the center frequency of the system.  Users are advised to expand the ground plane to approximately 36mm square, centered on the ceramic portion of the antenna (not the pin).  This can be done with copper foil soldered to the vias of the existing ground plane.
+
==uBlox Tips==
[[image:gps_antenna_comparison.jpg|thumb|500px|left|SAM-LS 25mm / Emtac 20mm / Emtac 18mm / Sangshin 18mm / Sangshin 13mm / Sarantel P2]]
 
<br style="clear:both">
 
  
=== Sangshin 18mm Patch ===
+
===Reset to Default Settings===
[[image:Sangshin_18mm.jpg|thumb|Sangshin 18mm x 4mm 1580Mhz]]
 
The Sangshin KSA-ST1580MS18 antenna has proven to offer the best performance of the currently available options.  These are available from any Sanshin distributor such as [http://www.rfmw.com rfmw] ([http://www.rfmw.com/PortalProductDetail.aspx?ProdId=232436&fmt=1 here]) and cost approximately $6.50/ea. in small quantities.
 
  
<br style="clear:both">
+
The GPS module can be reset to its original default settings by pulling BOOT_INT high(3.3V) during a power cycle ([http://www.u-blox.com/customersupport/gps.g4/ANTARIS4_Modules_SIM(GPS.G4-MS4-05007).pdf Antaris Manual, p. 122]). It may be required after a wrong firmware upgrade or a bad configuration change.
  
=== EMTAC 18mm Patch ===
+
===Invalid argument===
[[image:Emtac_18mm.jpg|thumb|Emtac 18mm x 4mm 1580Mhz]]
 
Offering identical performance to the Sangshin in a less attractive package is the Emtac 18mm antenna.  The part number for the standard 1580MHz 18x18x4mm is ANA1580T18D40 and is not listed on their website.  Other frequencies are available on a special order basis and the 1584Mhz has proven to outperform all other frequencies when used with a 36mm ground plane and no radome.  The use of a radome (any material covering the antenna) or a larger ground plane should theoretically favor even higher frequencies.
 
  
'''Availability'''
+
Problem:  I keep getting this error with my nice shiny Tiny v2.1 with a LEA-5H: Invalid_argument ("Latlong.of_utm")
 +
Solution: Select the correct [[Subsystem/gps|GPS subsystem]].
  
* [http://www.transplantgps.com/modules.html TransplantGPS] in MN, USA.  The 1580Mhz models are usually available at a cost of $3.55ea but there may be a minimum order requirement of ~$50 USD.
+
===WAAS issues===
* [http://www.onefastdaddy.com/catalog/product_info.php?products_id=43 PPZUAV] ~$10.00 USD (no min. order requirement)
 
<br style="clear:both">
 
  
=== Sangshin 13mm Patch ===
+
WAAS has been officially operational and "suitable for safety-of-life applications" since 2003.  The default setting of all u-blox receivers ignores WAAS correction data and only uses the WAAS satellites for regular navigation like any other satellite.  U-blox recommends further limiting this setting to exclude any stray EGNOS/MSAS satellites in North America, and completely disabling all SBAS functions for use outside North America.  In 2006 one formerly reliable Paparazzi aircraft began having great GPS problems and displaying very erratic altitude calculations, disabling WAAS immediately resolved the issue and this phenomenon was recreated several times for verification. Turns out a new WAAS satellite was being added to the system and the others were being moved that week for better distribution. Our advice is to first test if SBAS works well in your region.
  
[[image:Sangshin_13mm_onboard.jpg|thumb|Sangshin 13mm x 4mm 1580Mhz]]
+
The default used by the [[Module/GPS_UBlox_UCenter|u-blox UCenter module]] keeps SBAS enabled.  
Part of interest: '''[http://www.sangshinec.com/eng/patch_spec.htm KSA-ST1580MS13]'''
 
  
The Tiny 0.99 (not 0.9) and 1.1 were designed around this antenna but users are advised to install 18mm units for better performance.
+
===Assist Now===
 +
u-Blox modules that have a flash memory can keep the almanac correction data for up to 35 days into the future. That will give you a 3d GPS fix within seconds. [https://www.u-blox.com/en/assistnow-lock-your-position-instantly AssitNow] Offline data can be uploaded to the module while it is connected to the u-center application. To use this feature you need to provide a u-Blox account credentials that you can receive from the [https://www.u-blox.com/en/assistnow-service-registration-form u-Blox registration site].  
  
Size: 13 x 13 mm<br/>
+
===Antenna options for the Tiny and Paparazzi GPS units===
Center Frequency: 1580 MHz<br/>
+
See [[GPS/Antenna]].
Bandwidth: 5 MHz<br/>
 
@Fo: -15 dB<br/>
 
GAIN (dBi): 0 dBi<br/>
 
Ground Plane: 50 x 50 mm<br/>
 
  
'''Available From'''
+
=Tips=
  
[http://www.systroninc.com/ Systronic INC.] - Alberta, Canada
+
There is a huge amount of good information on the Internet about GPS specifics that gives some good insight into GPS. This Paparazzi wiki is not intended to repeat already available information, some is added here.
<br style="clear:both">
 
  
=== Emtac 20mm Patch ===
+
==EGNOS==
  
[[image:Salvaged_20mm_onboard.jpg|thumb|Emtac 20mm x 4mm]]
+
EGNOS augments the GPS satellite navigation system and makes it suitable for safety critical UAS applications. EGNOS became operational on 1 October 2009. ESA claims that it can determine position to within 2 meters compared with about 20 meters for GPS alone. Note that the service is currently provided only in western Europe. For further information take a look on the [http://www.esa.int/esaNA/egnos.html ESA EGNOS website].
The Tiny 0.9 was designed around this 1583Mhz antenna and performed extremely well. Emtac has replaced this with an 18mm model that they claim offers even better performance.
 
  
* Obsolete
+
For the latest update about functionality of EGNOS please check the website: [http://www.gsa.europa.eu European GNSS Supervisory Authority]"
<br style="clear:both">
 
  
=== Sarantel GeoHelix-P2 ===
+
==DGPS (Differential GPS)==
  
[[image:Geohelix-p2.jpg|thumb|Sarantel Geohelix P-2 1575Mhz]]
+
Differential GPS is any method of improving GPS accuracy by comparing the GPS-indicated position of a nearby location to the known value and transmitting any error to the mobile unit.  DGPS was originally created as a means of bypassing the deliberately introduced inaccuracies in civilian GPS signals.  The original method used low frequency ground radios to relay correction data to the mobile unit and is still used today at airports, shipping ports, and even individual farms.  Satellite Based Augmentation System (SBAS) is a modern form of DGPS where the ground stations relay correction data to a GEO-Stationary satellite, which then relays it to the mobile unit on standard GPS frequencies eliminating the need for a separate radio receiverSBAS is currently available in 3 regions, [http://www.esa.int/esaNA/ESAF530VMOC_egnos_1.html WAAS, EGNOS, and MSAS regions]. U-blox receivers support all common varieties of DGPS [http://www.u-blox.com/customersupport/gps.g3/ENGOS_Issues(GPS.G3-CS-04009).pdf read the u-blox SBAS application note].
 
+
* It is important to note that DGPS methods only improve the ''accuracy'' of the position calculation, not the ''precision''Since Paparazzi navigation is typically performed relative to the power-on location, any static error that could be corrected with DGPS is irrelevant.
This antenna is popular among UAV designers due to it's natural rejection of other radio frequencies such as those originating from the modem or video system as well as it's improved rejection of signals reflected from the ground.  U-blox recommends this antenna and features it in their [http://www.u-blox.com/news/sarantel.html reference design]. Frequency and polarization are not dependent upon ground plane geometry so this antenna is sold only in the true GPS frequency of 1575Mhz.
 
The geometry makes this antenna very inconvenient to mount, especially in an airplaneSome very non-scientific testing has been done with one of these antennas connected to a Tiny with a short length of 50 Ohm coax above a 120mm square of ungrounded aluminum foil and performance was adequate.  The helical design should theoretically outperform a patch in the air, but not on the ground, so any organized comparison will be difficult.  Possibly the most important aspect of this antenna is it's natural RFI filtering, which should be evaluated further.
 
  
* [http://www.sarantel.com/products/geohelix-p2 GeoHelix-P2] Passive GPS Antenna [[http://www.sarantel.com/downloads/specifications/geohelix-p2.pdf datasheet]]
+
[[Category:Hardware]] [[Category:Sensors]] [[Category:User_Documentation]]
 
 
 
 
'''Availability'''
 
 
 
* Sarantel @ cost of approx $18 USD each (active versions available for ~$40)
 
<br style="clear:both">
 
* [http://www.onefastdaddy.com/catalog/product_info.php?products_id=40&osCsid=709e839698120c5cd324072b77d67cc1 PPZUAV]
 

Latest revision as of 07:29, 5 July 2020


GPS Receivers

An overview of GPS receivers used in combination with Paparazzi. The list is by far not complete. A lot more devices will work flawlessly with Paparazzi. If you have a GPS receiver you have used with Paparazzi that is not listed here, it would be great if you could add that information to this page.

1BitSquared G0 GPS

G0 GPS

1BitSquared sells a Paparazzi UAV compatible GPS module called G0. It is designed to neatly fit on top of the Elle0 autopilot. It can also be used with any other Paparazzi UAV compatible hardware. G0 GPS module features a large ground plane with optional ground plane skirt, as well as RF shielding on the back of the module.

The large ground plane improves the directionality of the unit helping reject multi-path. When using the G0 GPS unit on a multi-copter it results in less drift when taking off the ground, and improves GPS lock when flying from waypoint to waypoint.

The EMI shielding on the back of the unit decreases the amount of noise injected from the aircraft avionics into the GPS unit, improving the noise to signal ratio. An increased signal results in a more robust satellite lock, and more reliable fully autonomous and guided flight operations.

G0 GPS module is using a U-Blox that is providing very fast speed updates that are crucial for accurate navigation within Paparazzi UAV. Additionally Paparazzi UAV supports the binary U-Blox protocol that is very efficient to parse compared to the very vaguely defined NMEA text protocol. Just enable the UCenter Module in your airframe file and Paparazzi will configure the module for best performance without the need for user interaction.

For more information go to the G0 GPS wiki page.


Swiftnav Piksi

A very special receiver is the OpenSource (almost all...) Swiftnav Piksi GPS receiver. How to use this device with Paparazzi is described on the a specific page

Swiftnav Piksi


LS20031 GPS Receiver

LS20031

Sparkfun sells the LS20031 GPS module which uses NMEA (Paparazzi support for NMEA is BETA right now.) This Locosys GPS module supports WAAS (U.S. DGPS), EGNOS (EU DGPS), and MSAS (Japanese DGPS).

More information on configuring the GPS via PMTK can be found here

Globalsat BU 353

BU-353 GPS receiver

USB US Globalsat GPS-Mouse

Typical Uses:

  • Parrot AR Drone 2.0
  • Ground Station GPS (direct support with Linux / gpsd)

Not appropriate for many airborne applications due to extra USB-serial circuitry and weight of housing and internal magnet

Basic compatibility with Windows, Mac and Linux.
More information at the GPS/BU_353 site.

uBlox

U-blox color warm 60.gif uBlox is a Swiss technology company that develops very good positioning modules. They are the recommended GPS modules for use with Paparazzi autopilots. Note that u-Blox produces the modules only. They do not sell complete boards to end users. These are sold by a multitude of vendors.

Why uBlox:

  • Low cost (i.e. NEO6-M)
  • Small size
  • Excellent performance (u-Blox 7 and 8 series)
  • Up to 10Hz update rate
  • 5V tolerant UART
  • Works out of the box with Paparazzi's u-Blox auto-configuration module

The Tiny series features an onboard LEA series GPS receiver and patch antenna, while most other boards boards require an external receiver+antenna such as the Paparazzi GPS or SAM-LS.

u-blox LEA GPS Receiver
u-Blox SAM-LS GPS receiver (w/built-in Smart Antenna)
u-Blox LEA-6H GPS receiver with Sarantel Helix Antenna

Note: The proprietary UBX protocol is used as it offers more information and efficiency than the universal NMEA protocol. For details take a look at the code in sw/airborne/subsystems/gps/gps_ubx.c.

u-Blox LEA Series Receivers

LEA-5H installed on the Tiny

The Lisa series, TWOG, Classix and AVR-based boards require an external GPS module and antenna. The Tiny features an integrated receiver and antenna. Either type is designed for u-blox 4, 5 and 6 series GPS receivers and the proprietary UBX binary protocol. An external battery or capacitor is typically used to enable the GPS to retain data while powered off for significantly faster signal re-acquisition. Any of the LEA-4, LEA-5 and LEA-6 series receivers can be used including the less expensive LEA-4A, 4S, 5A and 5S and similar low cost 6-series models as the special boot configuration code required for these models is already written as a module.

  <!-- autobaud - runtime configuration of - ROM-only modules: use ucenter-module to configure your UBlox with no cable nor windows u-center -->
  <load name="gps_ubx_ucenter.xml" />
  • 4Hz Position update rate
  • Supports active or passive antennas
  • Supports DGPS, WAAS, EGNOS, and MSAS
  • Low position noise figure


Paparazzi Stand-alone uBlox GPS Receivers

Paparazzi source provides a design for an external GPS board. An external GPS board is required for other boards like Lisa, TWOG, Elle0 and Classix. Programming it is similar to the Tiny2.11 GPS configuration. If you build your own you will want to upload the latest u-blox firmware before you configure. See Get Hardware for sources of assembled boards.

The Paparazzi design in https://github.com/paparazzi/paparazzi-hardware/tree/master/sensors/gps/gps_13. The board is very small and light as it has only the components required. It is powered from the 5v line on the "downloads" connector of a TWOG. Also note it is a 4-layer PCB that means better noise resistance. The board has pins for USB connection but requires a different cable and a solder jumper to be move from the ground (default) to 3.3v input to enable the USB port on the module.

V1 BOM.xls
Eagle Parts List Output.txt
See Get Hardware page for suppliers.

Wiring Diagram

TWOG to Standalone GPS Cable Schematic
GPS13 v0.9 Ucenter cable (ftdi)
BoozGPS (quadrotor gps V1.1 2009/5) Ucenter cable (ftdi)

uBlox to ARdrone 2

How to connect USB to uBlox Helix GPS for Parrot ARDrone2

To connect a uBlox with Helix antenna via a USB to serial cable that you can just plug into your ARdrone 2

3rd Party u-blox Reference Design Boards

LEA-5H Full Board Pinout

The only other GPS board in use seems to be u-blox reference designs or similar to it. They have LEA-4H, LEA-5H and LEA-6H (typically) and several interfaces. Often a larger antenna as well.

The board in the photo is a RF DESIGN LEA-5H-SMART.

The jumpers adjacent to the TTL interface connectors need to be closed with low value resistors for paparazzi uart port use. Also a battery has to be added with an appropriate charging resistor to enable RTC functionality.


NAVILOCK NL-507ETTL

NAVILOCK NL-507TTL

The NAVILOCK NL-507TTL u-blox TTL Modul 60416 features an LEA-4 series receiver and 25mm patch antenna on a 30mm x 30mm board.


SPK GS407

SPK GS407

This is the model Sparkfun recommends as a replacement for the old GS406. It's essentially the same, but uses the newer 6-series receiver, and is not using a ribbon cable as an interface. It uses Sarantels SL1206 active antenna. It's recommended to buy This extension cable to use with it.

u-blox NEO-6M

Hobbyking NEO 6M back

This is the cheapest GPS module with antenna for ~13€ at Hobbyking.

They come with different (sized) patch antenna, mounted on a separate PCB. The main PCB and antenna PCB are fixed with hot glue together and can be separated by hand.

Navilock NL-652ETTL

Nice module with u-blox 6 chip and without the annoying cable that the HK NEO-6m has. Navilock NL-652ETTL

u-Blox C04-6H Reference Design

u-blox C04-5H

u-Blox sells a complete module with antenna for around $200 and will also provide complete schematics, BOM, and PCB files for free if you wish to make your own. Two versions are offered, one with an 18mm patch antenna and the other with the Sarantel P2 helical antenna. See http://www.ublox.com/en/evaluation-tools-a-software/reference-designs/for-gps-chips/c04-6h.html for more info.

Drotek Boards

Drotek's u-Blox GPS boards work well and are not expensive.

uBlox GPS configuration

Using uBlox U-Center

Note: Before attempting manual configuration consider adding the u-blox UCenter module to your airframe instead. If automatic configuration does not work for you please make an issue in he gitgub issue tracker or report it to the mailing list or the Gitter chat and may attempt the manual procedure below. But be aware that a wrong configuration can cause Paparazzi not acquiring any GPS lock for sometimes hard to find reasons.

u-center configuration software

U-Center is an application intended for the configuration of u-Blox receivers.

TIP: If you want to direct access to the GPS module without unplugging from your autopilot board you can upload the UART tunnel firmware to your AP board.

Installation on Linux

Using the latest u-Center v8.27 is needed if you want to setup the uBlox GNSS receivers of the 8 series and use all setting available. We could use u-Center perfectly with Ubuntu 16.04 and the latest version of Wine v2.0.2.

Cut and paste this one-liner in you terminal to install just that:

 sudo dpkg --add-architecture i386 && \
 sudo apt-add-repository 'https://dl.winehq.org/wine-builds/ubuntu/' && \
 wget https://dl.winehq.org/wine-builds/Release.key && \
 sudo apt-key add Release.key && \
 sudo apt update && \
 sudo apt install winehq-stable
 mkdir -p ~/.wine/dosdevices &&\
 ln -s /dev/ttyUSB0 ~/.wine/dosdevices/COM1 && \
 ln -s /dev/ttyUSB0 ~/.wine/dosdevices/com1 && \
 ln -s /dev/ttyUSB1 ~/.wine/dosdevices/COM2 && \
 ln -s /dev/ttyUSB1 ~/.wine/dosdevices/com2
 

NOTE Depending on your connection method and your udev configuration your serial device may have a different path. Just look it up using dmesg or tail -f /var/log/syslog after plugging in.

Start U-center and choose your com port from the pull down list under the connect button near the top left corner of the window. Choose your baudrate from the pull down box to the right of the connect button or select the auto-baud button to the right of that. U-blox default is 9600 baud. This must be set to 57600 or higher to accommodate a 10Hz update rate. It needs to match whatever your module is configured with.
connect, baud, and autobaud buttons

Uploading the Configuration File

Download the appropriate configuration file below and use u-center to load in onto your receiver. Under the Tools menu, choose GPS configuration. Be sure the box 'Store configuration into BBR/Flash' is checked and hit the button File>>GPS. A few errors and retries are normal, but a significant number of errors may indicate a poor connection and the software will notify you if it is unable to send all the data successfully.

Automatic Configuration at Startup

You can also use the u-blox UCenter module which will take over the task of initializing the GPS for you when you power your autopilot.

Manual Configuration

If you prefer to setup your receiver manually or have a model not listed above, here are instructions to configure your receiver in u-center. Open the message window (menu View->messages view) to start the configuration process by changing the following settings:

LEA-4P

  1. Right Click on the NMEA Icon and choose disable child
  2. Choose UBX->CFG->NAV2(Navigation 2) - set it to use Airborne 4G (tells the Kalman filter to expect significant changes in direction)
  3. UBX->CFG->PRT - set USART1 to 38400bps (must match the value in your Airframe file)
  4. Change the baudrate of U-Center to 38400bps if the connection is lost at this point
  5. UBX->CFG->RXM(Receiver Manager) - change GPS Mode to 3 - Auto (Enabling faster bootup only if signal levels are very good)
  6. UBX->CFG->RATE(Rates) - change the Measurement Period to 250ms (4 Hz position updates)
  7. UBX->CFG->SBAS : Disable (SBAS appears to cause occasional severe altitude calcuation errors)
  8. UBX->NAV (not UBX->CFG->NAV): double click on POSUTM, SOL, STATUS, SVINFO, VELNED. They should change from grey to black
  9. UBX->CFG->CFG : save current config, click "send" in the lower left corner to permanently save these settings to the receiver

LEA-5H

  1. Right Click on the NMEA Text on top of the tree and choose disable child messages
  2. Choose UBX->CFG->NAV5(Navigation 5) - set it to use Airborne 8 <4G. This tells the Kalman filter to expect significant changes in direction.

    Note that this setting is only good for faster moving airplanes. For a fixed position hovering heli, 'pedestrian' setting is better

  3. UBX->CFG->PRT - set USART1 to 38400bps (must match the value in your Airframe file)
  4. Change the baudrate of U-Center to 38400bps if the connection is lost at this point
  5. UBX->CFG->RATE(Rates) - change the Measurement Period to 250ms This gives a 4 Hz position update since 4 x 250ms is one second.
  6. UBX->CFG->SBAS : Disable (SBAS appears to cause occasional severe altitude calculation errors)
  7. UBX->NAV (not UBX->CFG->NAV): double click on POSLLH, SOL, STATUS, SVINFO, VELNED. They should change from grey to black
  8. UBX->CFG->CFG : save current config, click "send" in the lower left corner to permanently save these settings to the receiver
  • Cycle the power and verify that the new configuration was saved
  • To reset the receiver to the factory defaults go to UBX->CFG->CFG, select 'Revert to default configuration', and click Send at the bottom left corner. To permanently save these values choose 'Save current configuration' and click Send.
  • To backup the configuration to a file on your PC: under the tools menu, choose GPS configuration, then click GPS>>file. This file can be re-loaded in a similar manner to configure additional identical receivers. Be sure the box 'Store configuration into BBR/Flash' is checked when reloading a configuration file to make the changes permanent.
  • To update the firmware on a LEA-5H get u-center >= 5.03, revert the GPS receiver to the default configuration, get an appropriate image from u-Blox (fitting your receivers serial number), find the flash identification flash.txt file in the u-center install directory and be prepared to wait a long time.
  1. NOTE: If you have a Tiny with LEA-5H module you must use u-center and manually setup the parameters as shown above (at least switch to 38400 baud manually before transferring the configuration file).
  2. NOTE: POSUTM is not available on LEA-5H. Instead, use POSLLH.

LEA-6H

We use the same configuration as for version 5

  1. Right Click on the NMEA Text on top of the tree and choose disable child messages
  2. Choose UBX->CFG->NAV5(Navigation 5) - set it to use Airborne 8 <4G. This tells the Kalman filter to expect significant changes in direction.

    Note that this setting is only good for faster moving airplanes. For a fixed position hovering heli, 'pedestrian' setting is better

  3. UBX->CFG->PRT - set USART1 to 38400bps (must match the value in your Airframe file)
  4. Change the baudrate of U-Center to 38400bps if the connection is lost at this point
  5. UBX->CFG->RATE(Rates) - change the Measurement Period to 250ms This gives a 4 Hz position update since 4 x 250ms is one second.
  6. UBX->CFG->SBAS : Disable (SBAS appears to cause occasional severe altitude calculation errors)
  7. UBX->NAV (not UBX->CFG->NAV): double click on POSLLH, SOL, STATUS, SVINFO, VELNED. They should change from grey to black
  8. UBX->CFG->CFG : save current config, click "send" in the lower left corner to permanently save these settings to the receiver.

    Make sure you activate "2 - I2C-EEPROM" if using a ROM-based NEO chipset with external EEPROM (like HK 31135)

  • Cycle the power and verify that the new configuration was saved
  • To reset the receiver to the factory defaults go to UBX->CFG->CFG, select 'Revert to default configuration', and click Send at the bottom left corner. To permanently save these values choose 'Save current configuration' and click Send.
  • To backup the configuration to a file on your PC: under the tools menu, choose GPS configuration, then click GPS>>file. This file can be re-loaded in a similar manner to configure additional identical receivers. Be sure the box 'Store configuration into BBR/Flash' is checked when reloading a configuration file to make the changes permanent.
  • To update the firmware on a LEA-6H get u-center >= 6.21, revert the GPS receiver to the default configuration, get an appropriate firmaware file from u-Blox, find the flash identification flash.txt file in the u-center install directory and be prepared to wait a long time.(seriously)

NEO-M8

  • UBX - CFG - PRT: disable NMEA output (only UBX protocol)
U-Center-PRT


  • UBX - CFG - MSG: activate PVT, SOL, SVINFO messages for UART1
U-Center-MSG


uBlox Tips

Reset to Default Settings

The GPS module can be reset to its original default settings by pulling BOOT_INT high(3.3V) during a power cycle (Antaris Manual, p. 122). It may be required after a wrong firmware upgrade or a bad configuration change.

Invalid argument

Problem: I keep getting this error with my nice shiny Tiny v2.1 with a LEA-5H: Invalid_argument ("Latlong.of_utm") Solution: Select the correct GPS subsystem.

WAAS issues

WAAS has been officially operational and "suitable for safety-of-life applications" since 2003. The default setting of all u-blox receivers ignores WAAS correction data and only uses the WAAS satellites for regular navigation like any other satellite. U-blox recommends further limiting this setting to exclude any stray EGNOS/MSAS satellites in North America, and completely disabling all SBAS functions for use outside North America. In 2006 one formerly reliable Paparazzi aircraft began having great GPS problems and displaying very erratic altitude calculations, disabling WAAS immediately resolved the issue and this phenomenon was recreated several times for verification. Turns out a new WAAS satellite was being added to the system and the others were being moved that week for better distribution. Our advice is to first test if SBAS works well in your region.

The default used by the u-blox UCenter module keeps SBAS enabled.

Assist Now

u-Blox modules that have a flash memory can keep the almanac correction data for up to 35 days into the future. That will give you a 3d GPS fix within seconds. AssitNow Offline data can be uploaded to the module while it is connected to the u-center application. To use this feature you need to provide a u-Blox account credentials that you can receive from the u-Blox registration site.

Antenna options for the Tiny and Paparazzi GPS units

See GPS/Antenna.

Tips

There is a huge amount of good information on the Internet about GPS specifics that gives some good insight into GPS. This Paparazzi wiki is not intended to repeat already available information, some is added here.

EGNOS

EGNOS augments the GPS satellite navigation system and makes it suitable for safety critical UAS applications. EGNOS became operational on 1 October 2009. ESA claims that it can determine position to within 2 meters compared with about 20 meters for GPS alone. Note that the service is currently provided only in western Europe. For further information take a look on the ESA EGNOS website.

For the latest update about functionality of EGNOS please check the website: European GNSS Supervisory Authority"

DGPS (Differential GPS)

Differential GPS is any method of improving GPS accuracy by comparing the GPS-indicated position of a nearby location to the known value and transmitting any error to the mobile unit. DGPS was originally created as a means of bypassing the deliberately introduced inaccuracies in civilian GPS signals. The original method used low frequency ground radios to relay correction data to the mobile unit and is still used today at airports, shipping ports, and even individual farms. Satellite Based Augmentation System (SBAS) is a modern form of DGPS where the ground stations relay correction data to a GEO-Stationary satellite, which then relays it to the mobile unit on standard GPS frequencies eliminating the need for a separate radio receiver. SBAS is currently available in 3 regions, WAAS, EGNOS, and MSAS regions. U-blox receivers support all common varieties of DGPS read the u-blox SBAS application note.

  • It is important to note that DGPS methods only improve the accuracy of the position calculation, not the precision. Since Paparazzi navigation is typically performed relative to the power-on location, any static error that could be corrected with DGPS is irrelevant.