Ok, sounds like thats normal then! Maybe I am miss-reading the offset, is it meant to mean offset of tractor to antenna? IE virtual antenna location?
Update time!
Some good news for sure, after many problems / confusion, Dual antenna is finally up and running, and what a difference, problem turned out to be the UART connection from one F9P to the other that sends across the RTCM corrections, was at to low a baud rate, causing the entire output to drop to 3-4hz, which was far to slow for AOG to make accurate steering calculations and just wouldnāt drive. After much testing with single F9P and good success, Franz figured it out, changed the configs, and now its working 100x better! So I really have to say at this point HUGE thanks to @Franz who has spent many hours looking at the code / trying to sort out the east / west problem for me. Massively appreciate it as has been quite the nightmare getting it working!
Problem with signal interference turned out to be the USB hub AGAINā¦ Believe it or not, I actually had this problem once before with another hub, a Chinese ebay specialā¦so canned it, and bought a decent Belkin branded item, turns out it has just the same issue. There USB3 hubs though, and doing some reading online, it seems USB3 can cause all kinds of issues, so maybe thats why! Either way, have put autosteer back on UDP again now as it was, so donāt need the hub anyway!
Have got things working with both PP and stanley, Found with PP it was stable at all speeds down to around 1.5kph, but to go slower, I have to massively drop gain, and then its fine, but with stanley Im able to run one setting at all speedsā¦
Quick video I made earlier testing, doesnāt look it, but is on the side of a hill so testing roll compensation here also, which is working great!
Massive thanks to @BrianTee_Admin for all his advice / and obviously for AOG itself!
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Great read, given me inspiration to fit this to our 6930
Got all the parts ordered, and part way through making a copy of your WAS bracket (I hope you donāt mind)!
I was wondering how you work out where exactly to bolt the sensor to the bracket, and the placement of the bracket on mudgaurd bolts, was it trial and error?
Be sure to post pics of your 6930 project on here, would be good to see.
Of course not, thats why its posted on here to hopefully help others!
I put power / multimeter on the sensor to work out its use-stroke on the bench, and eyballed the center, knowing that id always have the adjustable rod to get it spot onā¦
Small update to project,
Have now got the Dual GPS working on UDP again (Thanks Franz / Matt), which means no more USB connections to tablet, just single ethernet, also freeās up the wifi on the tablet again for if i need to connect to my mobile hotspot for when I am far from home / away from my long range wifi links.
Side update, in the few weeks I have been running, I have already noted on two occasions RTK2GO.com going downā¦One didnāt really effect me as wasnāt using it, but the other was mid field, right by the road, and caused me to make a bit of a mess! Decided I wasnāt hugely keen on the prospect of this failing in the future mid job, so spun up another VM on my virtual server in my rack at home, install SNIP, and pointed my ESP based NTRIP server to that, and changed AOG to connect to there instead, so now the NTRIP all stays within my own network / isnt relying on rtk2go.com anymore. All seems to be working great, not sure why I didnāt just do that originally really!
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Hi Darren,
Is the Dual over udp ethernet code up on git anywhere?
Interesting with rtk2go, I was going to us an esp connected to a 4g router sending to rtk2go as farm broadband sketchy.
How would you proceed if you was me now, as having server on 4g could run up big data useā¦my house in village has fibre over copper, should I do like you with a pi at home receiving from esp?
Using the Esp-xbee software as a caster directly rather than sending to rtk2go would significantly reduce data usage. Only sending data if you are actually connected.
How much range do you need if you setup a base station on the farm and use ardusimpleās extra long range radios? In other words, whatās the furthest field away from a good base station location?
Yes. A static IP or something like dyndnss is required.
The long range radios work well / many miles from what i understand when you have line of sightā¦but as soon as you dont, there hopelessā¦ With the hills around here it would be impossible to cover the entire farm really, hence went down the NTRIP routeā¦which appears to work great. Using RTK2GO has worked perfectly in all other respects, its just a couple times its been down (both times less than an hour) but still messed up a job that was otherwise going well, so just thought as I could, I would try and remove that risk by running my own casterā¦
Matts code is on Gitā¦Which uses the same UDP code anyway I think, just slightly different roll / heading calculations I think.
Reliable connection would deffo be critical, but 4G seems an expensive way to do itā¦If you home is near the farm, and has reliable broadband, I would set it up thereā¦
Didnāt think Mattās code had Ethernet in it, just WiFi & USB?
Was actually looking to use the 4g for other things also, like grain drier monitoring and security cameraās!
Agree with you on LR radios needing line of siteā¦hillās and woods here tooā¦although back in the day when cb radio was the farm communication it worked, but we had a great big antenna on the farm house roof and big whip antenna on tractors/combine!
CB radio also works on a completely different frequency and the radio wave propagates differently, works even without line-of-sight connection.
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Updateā¦
Been in the field alot this week, and overall, so so happy. Variety of jobs, and getting perfectly straight lines on the whole.
Only really two main issues at the moment.
1 - Am still finding in high draft / hill situations, AOG doesnāt command enough steering angle to maintain its position on line, it will pull it back on the line so far, and then just stop, Its like in a PID loop, with no I, so cant build gain and pull back on the lineā¦ as said 75% of the time its not a problem, but if you have any implements with side draft, or soil allowing the tractor to drift alot, it isnāt able to, working around it at the moment shifting the line uphill, which works as long as the hill is constant, but obviously if it changes during the run, will give a bend.
Spent alot of time messing with PID settings etc thinking I had it set wrong, but from what I can see, the arduino loop, of which is what you control with the PID settings in the autosteer section, are all for the loop that controls the outputā¦IE matches the real wheel angle, with the requested wheel angle from AOG? Which it is doing perfectly, and extremely smoothly now with latest version of AOG, there is never a situation where its drifting off line, and the actual steering angle isnt meeting the request, the problem is always that AOG just isnt asking for any further angle, despite it drifting further and further from the lineā¦ @BrianTee_Admin anything in the future possible to try and combat this behaviour?
2 - The only other problem which came apparent over the last few days relates to NTRIP, for the last week I have been working on one side of my farm which is largely covered by my long range wifi link to the tractor, and / or has good 4g cell coverage, so ntrip corrections have been 100% spot on, and its been driving superblyā¦
However this last few days I have been on the other side of a valley, where I donāt have my long range wifi (yet), so solely relying on 4g cell data, which on the whole is great, however nearly every field seems to have a tiny area / blackspot where it doesnāt work. Realistically these areas probably never add up to the tractor being out of data for more than 20-30 seconds, if thatā¦but its enough that AOG looses connection and starts to wait / attempt re connectingā¦ This is where I am running into some problems.
Loosing the ntrip corrections for 20-30 seconds in general shouldnt be an issue, as the F9P hangs onto the last known correction for i think 240 seconds anyway, which is always enough time to get data back / carry on. But for some reason, I am finding AOG keeps locking up momentarily / hanging up for a few seconds when its in the āwaitā or reconnecting stageā¦the numbers on the display will stop updating, and autosteer stops working, then a few seconds later it just clicks back into life and carries on. As said, never does this when connected / will run for hours faultlesslyā¦its just always in that moment of reconnection it seems to do itā¦which creates some issues as tractor will just move off line until it responds again.
Have just setup RTKLIB STRSVR and a virtual serial port, which acts as an NTRIP client and fowards to UDP (the F9P), so have disabled the AOG ntrip client, and will run with this over the next few days, to see if that removes that issue. if so, not really a hassle to just run that as the ntrip client, although it is useful to have it in AOG, as means you can keep an eye on its status easily from single windowā¦ Anyone else finding this ever happens? Maybe something specific to my setup / UDP comms?
Picture of the corrections working via rtklib:
Iām not really sure, but it could be something to do with getting the host ip/details in the background (unless this only runs at program startup?). iāve had issues with an older version where a 3g modem dropping out would briefly disconnect the windows network it was generating - and AgOpenGPS did not like that, even though rtklib/the gps had no issue with the internal ports/addresses they were using.
Are you using a router between your modem, and the AgOpenGPS computer?
No, it just connects directly to wifi tether on my mobile phoneā¦although technically my phone in that situation is acting as a routerā¦
Have ran it today with rtklib instead of the built in ntrip client, and works wonderfully, AOG dosnt glitch at all, and the F9P never went below RTK fix in entire fieldā¦STRSVR just dropped / carried on if the data disappeared for a few seconds, and AOG never knew any different 
Would be cool to figure out why the AOG client is causing problems, but this works great for now at least anywayā¦
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A thought to the problems I / a few others are having with AOG not pulling to the line in hillside / high draft situationsā¦
I use dual GPS, so AOG roll is turned off, as the incoming GPS feed is already roll compensatedā¦This means I cant use the hillside draft gain setting, as AOG has no roll to work withā¦
Was thinking if the option to use hillside draft but NOT roll compensation was allowed, it would be possible to send the roll value from ESP to AOG, or even just use the MMA for now, for the extra hillside draft gain which would potentially help the situation alotā¦ Granted still not ideal, as would be forever changing this setting I think for different conditions / implements, really just need to find a fix so it keeps pulling to the line with integral value in AOG calculation or somethingā¦
Thought id post some pictures over the last few days during silage here at home.
Super pleased overall with progress / working so well.
Have successfully overcome my glitching on RTK signal loss by using STRSVR from rtklib and turning of AOG ntrip client, now works smoothly 100% of time, made a huge difference, must be something specific to my setup as havenāt heard anyone else report those issues, but might be of help to someone if they do run into issues.
Quick video I made of a few clips:
And some photos:
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Nice work, how did you manage the wayline issue with the tool offset? I was thinking managing it with an antenna offset when I did a bit of raking with an old asymmetric tool.