Thank you for sharing! About to purchase rtk GPS for my standard robot mower. Skipped some now but will come back and watch again when I have all my equipment.
Thank you very much for the verbatim walk-through and explanations. I am building a custom mapping drone with RTK + heading using the F9P. While waiting on shipping I figured I would browse TH-cam for similar applications, yours at the nail on the head. Now off to read the manuals and data sheets for a deeper dive. By the way I watched the entire video!
Thank you for your positive feedback. I might mention that since I made this video, enhancements to Ardupilot have really simplified the setup, even with my method of bringing in the RTCM3 corrections directly from a separate telemetry receiver (in my case an Adafruit Feather M0 LoRa module). The stock ArduPilot firmware can completely set up both GPSs to work as desired. There is no need to have to do anything in Ucenter. Maybe I'll make another video sometime showing the steps now.
Thanks Kenny for taking time and effort in making the video, I did skip some - sorry but did watch about 90%! I don't have any RTK stuff but always have been interested in RTK.
Thank you very much for the verbatim walk-through and explanations. I am building a custom mapping drone with RTK + heading using the F9P. While I wait on shipping I figured I would browse TH-cam for similar applications. I think yours is all I need to jump right in and start testing, now off to read the manuals and do a little deeper dive.
Hi Kenny not sure how i missed this video, Ublox is the best in my opinion. I have found that as soon as I get to know a chip/Module, ardusimple come out with another module. I'm so happy your sticking with this platform. Kenny this is vital information even if that someone is myself in Melbourne Australia. At this point I'm sticking to the Base station Rover setup and as promised I'm hoping to get my Version 2 online today 6/11/22. Please "MAKE MORE VIDEOS" 😉
I watched the full video all the way through and don't even own the device yet. Currently in the process of reevaluating my life. :) On a more serious note - thank you for the video. Love to see you out there messing with stuff. Keep at it!
Thank you for the kind words. I have had a lot of "life" happening myself lately and not had time to work on my mower or make any additional videos. I hope to do so soon, though!
Hi Kenny. I’ve got the same Ublox Simple GPS but mine is just one unit that uses the satellites. It was very tricky to get it working with the Pixhawk Cube and had to try many different settings in Mission Planner but I managed to get it working. I must say that the accuracy was beyond my expectations and this will definitely be better for your mower. I look forward to how it works. All the best Kenny👍🏼
Great to hear! Thanks! I might mention that since I made this video, enhancements to Ardupilot have really simplified the setup, even with my method of bringing in the RTCM3 corrections directly from a separate telemetry receiver (in my case an Adafruit Feather M0 LoRa module). The stock ArduPilot firmware can completely set up both GPSs to work as desired. There is no need to have to do anything in Ucenter. Maybe I'll make another video sometime showing the steps now.
Hey Kenny, I just found an excerpt in the ZED-F9P datasheet related to 4072.1 message. "Message 4072.1 (timing information) is no longer necessary for moving base rover and as such it is no longer used by a moving base rover. To reduce the bandwidth requirements between a moving base rover and a moving base, it is recommended to disable RTCM 4072.1 output on the base"
Jason, thanks for pointing that out. I am letting ArduRover configure both GPSes since I learned that the Feather M0 LoRa can operate at 460800 baud rate that ArduRover uses for UART2 on both GPSes, so I don't have to configure anything in U-Center anymore. It would be interesting to see if the ArduRover configuration routine enables 4072.1, though.
@@KennyTrussell At 42:25 in your video section 2.2 the first sentence suggests 4072.1 was required on HPG 1.12 but no longer needed on HPG 1.13. Maybe that is the issue? I don't even own one of these yet, but am just watching out of curiosity.
Thank you for the kind words! I hope to get back to making more videos soon. One thing I want to show is how easy it is now with Ardupilot to implement Moving Baseline. A lot of the steps I went through in these videos are no longer necessary. Still, I think it helps to understand.
You and I are at similar levels, thank you so much for sharing this… I will pick up my snowblower again and make sure this works for next season Would love to see the mower in action
Hey Kenny, I watched it right the way through ... haha. Thanks for your efforts on this RTK and the various setup, I've been enjoying your videos on your mower for some time now, keep up the good work. My question is, do you really need two GPS boards (moving base) to get precision heading, or can it be done with a fixed station (either physically on site, or via corrections using a NTRIP source)? I'm assuming that prior to this point you were just using a compass on-board the mower and feeding that reading to ArduPilot?
Hi Hemon. A fixed GPS base, either onsite or via NTRIP, is required for precise POSITION. It does not contribute to heading at all. To get precise heading, you do need the second GPS on board. However, you do not have to have 2 GPS units on the mower, but it makes life a lot easier and tracking work better. A compass is not very accurate on a large metal object with large metal objects flying around (engine parts, blades, etc.) and magnetic and/or electromagnetic fields created by solenoids and other electric circuits. So, if you use a compass (as I did for 2 years), you have to calibrate the compass by operating the mower in circular patterns while the blades are turning. Even then, it isn't perfect. I hope one day to show a comparison of using a compass versus the "GPS for Yaw" AKA "Moving Baseline" method that uses the 2nd GPS on board. I actually expect that the compass will do pretty well, but not as well as the Moving Baseline.
@@KennyTrussellFirst, yes I did watch the entire video. ;-). Question: Do fixed base (NTRIP) corrections affect the accuracy of heading estimates at all in the Rover-Moving Base config? In other words, did the heading accuracy increase from your Config 3 to your Config 4?
Hi Kenny. Excellent video. The detail you go into is what makes it stand out. I watched it til the end and then went back and reviewed many sections. I'm a retired engineer(mech) in my 80's and enjoy building remote & autonomous ground vehicles. I am currently setting up 2 rtk2b boards as Base and Rover but haven't reached success yet. I think I may have at least 1 setting that is not correct. I dl the ardusimple config files and loaded them in the base and rover boards. I was able to "survey in" the base by setting 60 sec and 1 meter and got a fix mode of "TIME". Units are outside. I have not gotten a fix on the rover board. The "no rtk" led on the base stays on. I think my first priority is finding out why the "no rtk" led stays on.... Any particular reason you used uart2 instead of uart1?
Update: I sent a note to Ardusimple and they confirmed that the "RTK FIX" led on the Base stays on all the time but the "RTK FIX" led on the Rover goes off when its receiving corrections. So now I have everything working as it should!!
Thank you for the compliment, Jerry, and it is great to hear of your experimentation and success. I use UART2 because UART1 is connected to the flight controller on my autonomous mower. Also, unless things have changed, UART2 on the F9P is somewhat crippled and not capable of being used for some of the protocols. It does work with the RTCM3 corrections, so it is a good choice for that.
Great introduction to various F9P RTK setups... total newbie on the rtk business... I’m about to implement 2 Sparkfun F9P modules as fixed base and rover application for my electric motor robot mower based on a Purple Cube... but now consider buying a third one to get GPS-Yaw... some questions... in moving-base / rover setup, can i get both position and direction from the rover module,? Ie only one GPS connected to the Ardurover controller, or shall both GPS’s be connected to the controller?
Yes. All the heading and position information to the target system (in this case Ardurover) comes from the Rover GPS. The moving base GPS needs a connection to the Rover to send RTCM3 corrections to it. These corrections allow the Rover to accurately calculate its position RELATIVE to the moving base, so that it can know its heading from the moving base. It does NOT give it accurate absolution position (Lat/Lon) This RTCM3 path can either be through a direct wired connection, as I am using, or via the flight controller. If using the latter method, the flight controller is just passing the data coming in from the moving base GPS straight out to the rover GPS. Then, to have accurate absolute position (Lat/Lon), the moving base needs corrections from a fixed terrestrial base, so it needs a way to get RTCM3 fed into it from a fixed base. That can either be directly from a telemetry module as I am doing or can come from your ground control station (Mission Planner) via the normal telemetry path between it and Ardupilot using a protocol called MAVLink Injection. In that case, Ardupilot passes the corrections to the moving base. I would say most people use that latter method. I chose not to, so that I do not have to have a PC on every moment of the mission. This seems complicated at first, but it really is quite simple. And with the upcoming changes from the Ardupilot developers, it is getting easier. Jump on board and I hope you will share some videos of your mower!
Thank you for sharing your work. I'm in the initial building stage of a small brush-hog/mower similar to your mower. It looks like your using two receivers to get heading. Why not use a magnetic compass sensor? Are you planning on setting-up an RTK base station at your location?
Thanks for the nice comment. I have had my mower operating for about 3 years. If you look at my older videos, I think you will see that I have had an RTK base at my location for most of that time. A few months ago I had a project for the company I worked for which required an RTK base. I chose to move the base I had been using to a location suitable for that project. It uploads its corrections to an NTRIP server at rtk2go.com and then I can use it anywhere I have internet access. So, that is what I am doing currently. The base is located 26 miles away. It has given me surprisingly good accuracy and repeatability. But, I do plan to install a base again here at my location. I hope to get that done in the next few days, actually. On the question of using a magnetometer for heading, I used one for 2 years. The problem with such a sensitive device is that the flying metal of a mower, gasoline engine, or perhaps more so the electromagnetic fields produced by the ignition system or PTO soloenoid can cause incorrect readings. I recorded a demonstration of this phenomenon at th-cam.com/video/gBn3Eygo88o/w-d-xo.html. I will say, though, that I did a lot of useful mowing with that system. In fact, I can't say I saw an immediate huge difference when I implemented the GPS for Yaw (2nd GPS) feature. What really made the difference in getting good pivot turns is when the most recent changes to ArduRover fixed a bug. (Sorry for such a long response!) Good luck with your project. I would really like to know more about it. I hope to build a larger vehicle capable of more heavy duty work, one day.
@@KennyTrussell Thanks for getting back. I did look deeper in to your other videos and found your base station setup. Sorry to comment without first looking at your history. Have you covered using magnetometer (compas) and gyroscope (pitch and yaw) modules before? Have you described the servos and drivers you are using? Thanks again for sharing. PS Great looking donkey and goats.
Hi Kenny, Thanks for the really well put together video. A question if I may. Did you try running your moving base Hz at anything higher than 1Hz? My project really needs 10Hz minimum update rate.
Hi Paul, The RTCM3 communication from either a fixed base gps or a moving base gps to a moving base gps or rover gps is normally at 1 Hz. Some of the messages can be even slower, as in once each 5 seconds. I have all my RTCM3 messages at 1 Hz. The communication from the moving base gps and the rover gps into the flight controller is at 5 Hz. That is the recommended rate. The F9P is capable of sending updates at 10 Hz, but according to the ArduPilot developers, bandwidth becomes an issue at 10 Hz. Also, there is no advantage of 10 Hz over 5 Hz. See discuss.ardupilot.org/t/yuris-mower-updates/71100/121. Of course, if you application has nothing to do with ArduPilot, my comments may not help.
Hi Kenny, Thanks for replying to my question. Since watching your video I have managed to get a moving base working. I'm running both the base and rover at 5hz. I'm no expert but it looks like a moving base requires an rtcm correction message once every update. So if I want to read rover data at 5hz then the base has to deliver 5 rtcm corrections per second. That's around 400kbps data over uart. I've tried 10hz and can't get it working properly. 5hz should be fine for my robot lawnmower application. Anyway you kind of already said all that in your reply. I'm fascinated by this method of heading measurement. I was previously using rtk heading but found it was a little sketchy at the lower speeds the mower goes at. I then made a 3 axis tilt compensated compass but of course the compass has a heap of issues that at my level are hard to manage. This MB solution should be a great solution !!
Hi Kenny, I thank you for sharing that you propose because they are very interesting. I do much more modest work. I am on the basis of an F9p connected to RtkNavi with a personal Processing-Arduino application, all on a Pc W10. My Rover Rtk starts working properly between 2 WPoints. This is just the beginning of a long adventure!! I read somewhere that it was possible to perform the Rtcm correction directly on the F9p without using RtkLib. Would you have a few moments to document me on this point? Thank you for all the videos and informations that you broadcast and that allowed me to learn.
I may not fully understand your question, but I'll say that you can communicate RTCM3 from a serial port on an F9P base to a serial port on an F9P rover via any telemetry that can handle the bandwidth, which is not very hard. I am using LoRa modules from Adafruit, but you can use other serial to RF telemetry systems. You do not have to have a computer or Raspberry Pi running RTKLib if that is what you are trying to do.
Great video, I just purchased this in a starter kit form. What's the difference in performance in using Rover and Rover with corrections versus using Rover and moving base with corrections?
Rover alone will only give you around 2 meter accuracy. Rover with corrections from a fixed base will give you accuracy approaching 1 cm. A moving base will not really improve positional accuracy but will give accurate heading information even when the Rover is not moving.
Hi Kenny. You may not be monitoring this message board but just in case you are I have a question. I have disabled all the nmea sentences except GNGGA and monitoring 2 rtk2b boards on the rover with a python program thru the micro b USB port. One of the boards is sending only the GNGGA sentence but the other one along with the GNGGA sentence is sending about 50 or so characters with a format like "b'\xb5b\x01\\x04\se8......." and on and on and then sends the GNGGA sentence. Do you know what is sending the extra characters and how to shut them off. Only 1 of the boards is sending this. The other board is sending only the GNGGA sentence. btw I saw your video on the fire....pretty spectacular! Looking for more videos. Thanks. bye
The strange string you are seeing is the ASCII and hexidecimal representation of binary data coming across. UBX and RTCM3 send binary, not ASCII text. I would bet that you have UBX or RTCM3X messages enabled on that RTK2B. You can go to the CFG-USBOUTPROT and turn off the RTCM3X and UBX. There is one gotcha: Once you turn off UBX, then you will not be able to configure the device anymore through the USB port until you turn it back on. So, be sure you have everything else configured properly. You might find it better to use the UART1 port of the board if you can and let the USB port be avaiable for connecting ucenter, but I don't know your hardware setup. Thanks for the complement. I do hope to get more videos out soon!
No. I have never had trouble with them. I haven't loaded them very often, though. I normally manually configure what I need for the base. I wonder if the version of firmware in your F9P is not compatible with the files. I really don't know. Sorry.
Thank you for sharing! About to purchase rtk GPS for my standard robot mower. Skipped some now but will come back and watch again when I have all my equipment.
That's great Lawrence. I look forward to hearing how it all works for you. Maybe you can share a video of it working with RTK!
Thank you very much for the verbatim walk-through and explanations. I am building a custom mapping drone with RTK + heading using the F9P. While waiting on shipping I figured I would browse TH-cam for similar applications, yours at the nail on the head. Now off to read the manuals and data sheets for a deeper dive.
By the way I watched the entire video!
Thank you for your positive feedback. I might mention that since I made this video, enhancements to Ardupilot have really simplified the setup, even with my method of bringing in the RTCM3 corrections directly from a separate telemetry receiver (in my case an Adafruit Feather M0 LoRa module).
The stock ArduPilot firmware can completely set up both GPSs to work as desired. There is no need to have to do anything in Ucenter. Maybe I'll make another video sometime showing the steps now.
@@KennyTrussell Good to hear, and that would be awesome!
Thanks Kenny for taking time and effort in making the video, I did skip some - sorry but did watch about 90%!
I don't have any RTK stuff but always have been interested in RTK.
Thank you so much for your kind comments!
Thank you very much for the verbatim walk-through and explanations. I am building a custom mapping drone with RTK + heading using the F9P. While I wait on shipping I figured I would browse TH-cam for similar applications. I think yours is all I need to jump right in and start testing, now off to read the manuals and do a little deeper dive.
Hi Kenny not sure how i missed this video, Ublox is the best in my opinion. I have found that as soon as I get to know a chip/Module, ardusimple come out with another module.
I'm so happy your sticking with this platform. Kenny this is vital information even if that someone is myself in Melbourne Australia.
At this point I'm sticking to the Base station Rover setup and as promised I'm hoping to get my Version 2 online today 6/11/22.
Please "MAKE MORE VIDEOS" 😉
I hope to get back into videos soon.
I watched the full video all the way through and don't even own the device yet. Currently in the process of reevaluating my life. :) On a more serious note - thank you for the video. Love to see you out there messing with stuff. Keep at it!
Thank you for the kind words. I have had a lot of "life" happening myself lately and not had time to work on my mower or make any additional videos. I hope to do so soon, though!
Hi Kenny. I’ve got the same Ublox Simple GPS but mine is just one unit that uses the satellites.
It was very tricky to get it working with the Pixhawk Cube and had to try many different settings in Mission Planner but I managed to get it working.
I must say that the accuracy was beyond my expectations and this will definitely be better for your mower. I look forward to how it works. All the best Kenny👍🏼
Thank you for your kind comments!
It saved me hours of experimentation. Thanks!
Great to hear! Thanks!
I might mention that since I made this video, enhancements to Ardupilot have really simplified the setup, even with my method of bringing in the RTCM3 corrections directly from a separate telemetry receiver (in my case an Adafruit Feather M0 LoRa module).
The stock ArduPilot firmware can completely set up both GPSs to work as desired. There is no need to have to do anything in Ucenter. Maybe I'll make another video sometime showing the steps now.
I looked all through and repeated it, yes it is very useful for me for starting my project thanks.
Thank you. What type of project are you starting?
Hey Kenny, I just found an excerpt in the ZED-F9P datasheet related to 4072.1 message. "Message 4072.1 (timing information) is no longer necessary for moving base rover and
as such it is no longer used by a moving base rover. To reduce the bandwidth requirements
between a moving base rover and a moving base, it is recommended to disable RTCM 4072.1
output on the base"
Jason, thanks for pointing that out. I am letting ArduRover configure both GPSes since I learned that the Feather M0 LoRa can operate at 460800 baud rate that ArduRover uses for UART2 on both GPSes, so I don't have to configure anything in U-Center anymore. It would be interesting to see if the ArduRover configuration routine enables 4072.1, though.
@@KennyTrussell At 42:25 in your video section 2.2 the first sentence suggests 4072.1 was required on HPG 1.12 but no longer needed on HPG 1.13. Maybe that is the issue? I don't even own one of these yet, but am just watching out of curiosity.
This is all so informative to me Kenny. Thanks so much for taking the time to make this video.
Thank you for the kind words! I hope to get back to making more videos soon. One thing I want to show is how easy it is now with Ardupilot to implement Moving Baseline. A lot of the steps I went through in these videos are no longer necessary. Still, I think it helps to understand.
You and I are at similar levels, thank you so much for sharing this… I will pick up my snowblower again and make sure this works for next season
Would love to see the mower in action
Thanks for the kind words. I look forward to seeing your machine. And I will happily demonstrate my mower anytime.
Hey Kenny, I watched it right the way through ... haha. Thanks for your efforts on this RTK and the various setup, I've been enjoying your videos on your mower for some time now, keep up the good work. My question is, do you really need two GPS boards (moving base) to get precision heading, or can it be done with a fixed station (either physically on site, or via corrections using a NTRIP source)? I'm assuming that prior to this point you were just using a compass on-board the mower and feeding that reading to ArduPilot?
Hi Hemon. A fixed GPS base, either onsite or via NTRIP, is required for precise POSITION. It does not contribute to heading at all. To get precise heading, you do need the second GPS on board.
However, you do not have to have 2 GPS units on the mower, but it makes life a lot easier and tracking work better. A compass is not very accurate on a large metal object with large metal objects flying around (engine parts, blades, etc.) and magnetic and/or electromagnetic fields created by solenoids and other electric circuits. So, if you use a compass (as I did for 2 years), you have to calibrate the compass by operating the mower in circular patterns while the blades are turning. Even then, it isn't perfect. I hope one day to show a comparison of using a compass versus the "GPS for Yaw" AKA "Moving Baseline" method that uses the 2nd GPS on board. I actually expect that the compass will do pretty well, but not as well as the Moving Baseline.
@@KennyTrussellFirst, yes I did watch the entire video. ;-). Question: Do fixed base (NTRIP) corrections affect the accuracy of heading estimates at all in the Rover-Moving Base config? In other words, did the heading accuracy increase from your Config 3 to your Config 4?
Hi Kenny. Excellent video. The detail you go into is what makes it stand out. I watched it til the end and then went back and reviewed many sections. I'm a retired engineer(mech) in my 80's and enjoy building remote & autonomous ground vehicles. I am currently setting up 2 rtk2b boards as Base and Rover but haven't reached success yet. I think I may have at least 1 setting that is not correct. I dl the ardusimple config files and loaded them in the base and rover boards. I was able to "survey in" the base by setting 60 sec and 1 meter and got a fix mode of "TIME". Units are outside. I have not gotten a fix on the rover board. The "no rtk" led on the base stays on. I think my first priority is finding out why the "no rtk" led stays on.... Any particular reason you used uart2 instead of uart1?
Update: I sent a note to Ardusimple and they confirmed that the "RTK FIX" led on the Base stays on all the time but the "RTK FIX" led on the Rover goes off when its receiving corrections. So now I have everything working as it should!!
Thank you for the compliment, Jerry, and it is great to hear of your experimentation and success. I use UART2 because UART1 is connected to the flight controller on my autonomous mower. Also, unless things have changed, UART2 on the F9P is somewhat crippled and not capable of being used for some of the protocols. It does work with the RTCM3 corrections, so it is a good choice for that.
Great introduction to various F9P RTK setups... total newbie on the rtk business... I’m about to implement 2 Sparkfun F9P modules as fixed base and rover application for my electric motor robot mower based on a Purple Cube... but now consider buying a third one to get GPS-Yaw... some questions... in moving-base / rover setup, can i get both position and direction from the rover module,? Ie only one GPS connected to the Ardurover controller, or shall both GPS’s be connected to the controller?
Yes. All the heading and position information to the target system (in this case Ardurover) comes from the Rover GPS.
The moving base GPS needs a connection to the Rover to send RTCM3 corrections to it. These corrections allow the Rover to accurately calculate its position RELATIVE to the moving base, so that it can know its heading from the moving base. It does NOT give it accurate absolution position (Lat/Lon) This RTCM3 path can either be through a direct wired connection, as I am using, or via the flight controller. If using the latter method, the flight controller is just passing the data coming in from the moving base GPS straight out to the rover GPS.
Then, to have accurate absolute position (Lat/Lon), the moving base needs corrections from a fixed terrestrial base, so it needs a way to get RTCM3 fed into it from a fixed base. That can either be directly from a telemetry module as I am doing or can come from your ground control station (Mission Planner) via the normal telemetry path between it and Ardupilot using a protocol called MAVLink Injection. In that case, Ardupilot passes the corrections to the moving base. I would say most people use that latter method. I chose not to, so that I do not have to have a PC on every moment of the mission.
This seems complicated at first, but it really is quite simple. And with the upcoming changes from the Ardupilot developers, it is getting easier.
Jump on board and I hope you will share some videos of your mower!
Thank you for sharing your work.
I'm in the initial building stage of a small brush-hog/mower similar to your mower.
It looks like your using two receivers to get heading. Why not use a magnetic compass sensor?
Are you planning on setting-up an RTK base station at your location?
Thanks for the nice comment. I have had my mower operating for about 3 years. If you look at my older videos, I think you will see that I have had an RTK base at my location for most of that time. A few months ago I had a project for the company I worked for which required an RTK base. I chose to move the base I had been using to a location suitable for that project. It uploads its corrections to an NTRIP server at rtk2go.com and then I can use it anywhere I have internet access. So, that is what I am doing currently. The base is located 26 miles away. It has given me surprisingly good accuracy and repeatability. But, I do plan to install a base again here at my location. I hope to get that done in the next few days, actually.
On the question of using a magnetometer for heading, I used one for 2 years. The problem with such a sensitive device is that the flying metal of a mower, gasoline engine, or perhaps more so the electromagnetic fields produced by the ignition system or PTO soloenoid can cause incorrect readings. I recorded a demonstration of this phenomenon at th-cam.com/video/gBn3Eygo88o/w-d-xo.html.
I will say, though, that I did a lot of useful mowing with that system. In fact, I can't say I saw an immediate huge difference when I implemented the GPS for Yaw (2nd GPS) feature. What really made the difference in getting good pivot turns is when the most recent changes to ArduRover fixed a bug. (Sorry for such a long response!)
Good luck with your project. I would really like to know more about it.
I hope to build a larger vehicle capable of more heavy duty work, one day.
@@KennyTrussell Thanks for getting back.
I did look deeper in to your other videos and found your base station setup. Sorry to comment without first looking at your history.
Have you covered using magnetometer (compas) and gyroscope (pitch and yaw) modules before?
Have you described the servos and drivers you are using?
Thanks again for sharing.
PS Great looking donkey and goats.
Hi Kenny,
Thanks for the really well put together video.
A question if I may. Did you try running your moving base Hz at anything higher than 1Hz?
My project really needs 10Hz minimum update rate.
Hi Paul,
The RTCM3 communication from either a fixed base gps or a moving base gps to a moving base gps or rover gps is normally at 1 Hz. Some of the messages can be even slower, as in once each 5 seconds. I have all my RTCM3 messages at 1 Hz. The communication from the moving base gps and the rover gps into the flight controller is at 5 Hz. That is the recommended rate. The F9P is capable of sending updates at 10 Hz, but according to the ArduPilot developers, bandwidth becomes an issue at 10 Hz. Also, there is no advantage of 10 Hz over 5 Hz. See discuss.ardupilot.org/t/yuris-mower-updates/71100/121.
Of course, if you application has nothing to do with ArduPilot, my comments may not help.
Hi Kenny,
Thanks for replying to my question.
Since watching your video I have managed to get a moving base working. I'm running both the base and rover at 5hz.
I'm no expert but it looks like a moving base requires an rtcm correction message once every update. So if I want to read rover data at 5hz then the base has to deliver 5 rtcm corrections per second. That's around 400kbps data over uart.
I've tried 10hz and can't get it working properly. 5hz should be fine for my robot lawnmower application.
Anyway you kind of already said all that in your reply.
I'm fascinated by this method of heading measurement.
I was previously using rtk heading but found it was a little sketchy at the lower speeds the mower goes at.
I then made a 3 axis tilt compensated compass but of course the compass has a heap of issues that at my level are hard to manage.
This MB solution should be a great solution !!
Hi Kenny, I thank you for sharing that you propose because they are very interesting.
I do much more modest work. I am on the basis of an F9p connected to RtkNavi with a personal Processing-Arduino application, all on a Pc W10. My Rover Rtk starts working properly between 2 WPoints. This is just the beginning of a long adventure!!
I read somewhere that it was possible to perform the Rtcm correction directly on the F9p without using RtkLib. Would you have a few moments to document me on this point?
Thank you for all the videos and informations that you broadcast and that allowed me to learn.
I may not fully understand your question, but I'll say that you can communicate RTCM3 from a serial port on an F9P base to a serial port on an F9P rover via any telemetry that can handle the bandwidth, which is not very hard. I am using LoRa modules from Adafruit, but you can use other serial to RF telemetry systems. You do not have to have a computer or Raspberry Pi running RTKLib if that is what you are trying to do.
Great video, I just purchased this in a starter kit form. What's the difference in performance in using Rover and Rover with corrections versus using Rover and moving base with corrections?
Rover alone will only give you around 2 meter accuracy.
Rover with corrections from a fixed base will give you accuracy approaching 1 cm.
A moving base will not really improve positional accuracy but will give accurate heading information even when the Rover is not moving.
Hi Kenny. You may not be monitoring this message board but just in case you are I have a question. I have disabled all the nmea sentences except GNGGA and monitoring 2 rtk2b boards on the rover with a python program thru the micro b USB port. One of the boards is sending only the GNGGA sentence but the other one along with the GNGGA sentence is sending about 50 or so characters with a format like "b'\xb5b\x01\\x04\se8......." and on and on and then sends the GNGGA sentence. Do you know what is sending the extra characters and how to shut them off. Only 1 of the boards is sending this. The other board is sending only the GNGGA sentence.
btw I saw your video on the fire....pretty spectacular! Looking for more videos. Thanks. bye
The strange string you are seeing is the ASCII and hexidecimal representation of binary data coming across. UBX and RTCM3 send binary, not ASCII text. I would bet that you have UBX or RTCM3X messages enabled on that RTK2B. You can go to the CFG-USBOUTPROT and turn off the RTCM3X and UBX. There is one gotcha: Once you turn off UBX, then you will not be able to configure the device anymore through the USB port until you turn it back on. So, be sure you have everything else configured properly. You might find it better to use the UART1 port of the board if you can and let the USB port be avaiable for connecting ucenter, but I don't know your hardware setup.
Thanks for the complement. I do hope to get more videos out soon!
Hello, can you tell me why the F9P Base config C99 configuration files are not loading?
No. I have never had trouble with them. I haven't loaded them very often, though. I normally manually configure what I need for the base.
I wonder if the version of firmware in your F9P is not compatible with the files. I really don't know. Sorry.
Hi Kenny, Could you please upload the file RTCM3 to Uart2 config file?
I'm sorry to be so long before replying. Do you still need this?
@@KennyTrussell Hi ,no I don't need it now.But maybe someone else might need it.