AOG 6.8.3, ArduSimple F9P single antenna.
Is there a way to get heading into a Machine module without having any AutoSteer/IMU equipment?
I’m thinking about implementing turn compensation for a boom. Yaw rate would be best, guessing I can calculate that if I can get heading info?
AOG send the 64 sections PGN which contains the speed of each extremity of the boom.
Should be fine for your use?
Thanks for the suggestion. With the simulator, when receiving this PGN:
Byte5 contains the correct section info, but bytes 13 & 14 are both 0 while at speed and in a tight turn.
At the same time PGN 239 Byte6 (Speed*10), is returning the correct speed. ???
Digging into Machine PGNs a bit more I find some inconsistencies with the documentation. I wonder if the Lspeed/Rspeed exists in another part of another PGN?
No negative value? So I guess you would need to use center and the higher side if one side is 0.
Odd that you see speed at the 9-16 sections byte.
I’ve only been messing with these PGNs for a couple weeks. Lots to learn.
I thought all the bytes in the DataPackage for all PGNs was unsigned 8 bit byte. Are some bytes in the DataPackage signed 8 bit bytes?
Its unclear to me. I was looking at Lspeed/Rspeed as being absolute speed of the outer tips of a spray boom.
I think, from what you are saying, since in a tight turn the inside(slow) tip could go to a negative speed, and the PGN dataLoad uses unsigned integers, a negative speed cannot be directly represented by uint8_t
So the Lspeed/Rspeed pair will report the faster tip as a uint8_t with a value representing incremental increase, while the slower tip shows 0x00.
Then use some arithmetic to figure the speed of slow tip (equal scalar but opposite sign) reduced from center speed?
But I still need to get a non zero value for one of the variables in the Lspeed/Rspeed pair.
Or am I way off base, and totally confused?
In simulator, while driving around swerving left and right, and at varying speeds, I can sometimes get Lspeed to show 1, but Rspeed is always 0. I can’t find a driving pattern to get Lspeed =1, it almost seems random. I’m thinking that Autosteer or IMU (which I don’t have) is used to populate those PGN bytes. In any case a value of 1 is not meaningful for me.
It seems that Lspeed/Rspeed will not be usable for me to use in adjusting PWM nozzle values in turn compensation.
Maybe somebody has an answer, but I’m losing hope I can accomplish PWM turn compensation without AutoSteer.
This is embarrassing. In parsing PGN 239 I was getting zero for Lspeed/Rspeed, causing me to abandon that approach.
Turns out my parsing code was flawed. Fixing my code then the Lspeed/Rspeed are there.
I now have the turn compensation working using Lspeed/Rspeed. Plus I learned how the get yaw rate from an standalone external IMU.
Thanks all who contributed.
