[Feature Request] Add "Base Assisted" Mode

[PaulZC]

As requested by @doug-foster in #737 and #723 . This request needs its own issue...

“Base Assisted” would:
Be a new System Menu Option (Base, BaseCaster, BaseAssisted, Rover, Web Config, Shutdown)
Initialize as a Rover
Remain as a Rover until RTK-FIX was achieved
Continue as a Rover for a small period of time (30 seconds?) to verify RTK-FIX had quiesced.
Restart as a Base using the newly acquired, quiesced fixed (Rover) coordinates.
Skip survey-in
Begin generating RTCM

@PaulZC 's summary - I think we can condense this to:
When selecting the new Base Assisted mode, the current (Rover) position is copied to the Fixed Base coordinates for the current profile
Fixed Base starts as normal using those updated coordinates
The user would need to manually ensure that RTK Fix was achieved and the horizontal accuracy was acceptable before selecting Base Assisted

[doug-foster]

Your summary is helpful Paul, but the use case I see for this feature is when a base/rover pair used with each survey being a new, different location. IMO, you pick where you want your control point, mark it, set the base over it, and power up. No fiddling with settings or buttons in the field. The device boots, loads a profile, starts in rover mode, connects to a correction source, establishes RTK-FIX, then changes to fixed base mode generating RTCM for the rover. No user intervention, set it, power it, that's it.

An example:
This summer we surveyed a cemetery in Iowa (https://www.findagrave.com/cemetery/1676398/saints-peter-and-paul-cemetery) for my wife's new book. If I plot the graves in QGIS using the findagrave coordinates (cell phoneGPS) it's a scrambled mess. So we did a more precise survey using the Sparkfun GPS-RTK-SMA rover I built and the Sparkfun EVK as a temporary base. It was hotter than hell, sweat dripping from my forehead, and the last thing I wanted to be doing was configure the EVK over BT (Issue 723) in full sun, or toggle the mode button and watch my .014m HAC accurate rover position disappear as the base ran a 60 second survey in and started sending RTCM to the rover. So I screenshotted the coordinates, set up the EVK as a fixed base w/o survey, and rebooted. All the while sweating like crazy, swatting mosquitos, and messing with both serial & BT configs for the EVK. The ideal situation would have been set, power, & start roving.

[PaulZC]

Thanks Doug (@doug-foster ) - that's helpful,

We have a fix for #723 / #737 - Nathan is kicking the tyres as I type. Being able to use BT to reliably switch from Rover to Base, and vice versa, will make your life a lot easier.

I must admit I'm nervous about implementing a Rover NTRIP-assisted "survey-in". It would need a reliable state machine or other logic to decide when to go from Rover to Base. It would need, as a minimum, a timer or a horizontal accuracy check. What if the NTRIP corrections don't arrive, and it never achieves Fix? What does it do then? I can envisage the steam rising from your collar as you try to figure out why it hasn't changed mode and your other Rover isn't getting its corrections.

In my mind, it's much cleaner to ask the user to select Rover, check corrections arrive, check RTK Fix is achieved, and then the user decides when to select Base Assisted with a few keystrokes on Serial Bluetooth Terminal.

I'm very happy to continue discussing this - but probably on Monday. It's almost the weekend here... ;-)

[doug-foster]

I saw the commit. Great news Paul, thanks!

Good points, I have some thoughts, but let's save those for next week. Enjoy the weekend!

[PaulZC]

I'm starting to add the code for this.

My plan is to keep it really simple. Selecting Base Assist (from the Menu, or using the button) will:
Copy the current GNSS position into the settings (overwriting fixedLat/Long/Altitude, fixedEcefX/Y/Z)
Set fixedBase to true
Change to Base mode

So, this covers going from Rover (e.g. with RTK Fix) to Fixed Base and going from Temporary Base (after Survey-In) to Fixed Base.

It's a nice add @doug-foster . Thanks again for the suggestion!

[doug-foster]

Oh boy, early Christmas present! :-)Seriously, sounds like a plan Paul. As you mentioned in an earlier comment, implementing Assisted Base as a single step setting (switching from rover to base automatically when RTK Fix is achieved) raises a bunch of questions. KISS works.DougSent from my iPhoneOn Nov 27, 2025, at 8:18 AM, Paul Clark ***@***.***> wrote:PaulZC left a comment (sparkfun/SparkFun_RTK_Everywhere_Firmware#751) I'm starting to add the code for this. My plan is to keep it really simple. Selecting Base Assist (from the Menu, or using the button) will: Copy the current GNSS position into the settings (overwriting fixedLat/Long/Altitude, fixedEcefX/Y/Z) Set fixedBase to true Change to Base mode So, this covers going from Rover (e.g. with RTK Fix) to Fixed Base and going from Temporary Base (after Survey-In) to Fixed Base. It's a nice add @doug-foster . Thanks again for the suggestion! —Reply to this email directly, view it on GitHub, or unsubscribe.You are receiving this because you were mentioned.Message ID: ***@***.***>