In the spreadsheet the GPS heading is in column I
AimPoint is in column O
the error for the PID is either I-o or O-I can not remember I minus will make a turn one way and a + will make a turn the other way
The error will generate a turnspeed as recorded in column U.
This is then apportioned (added and subtracted ) to the left and right wheel speeds ie with a constant forward speed of 550.
the robot drives and then we calculate the error in cross track ie the CTE. This value is not currently feedback as we only use the aimpoint gps error.
Shortly we are going to implement a separate PID to be totally comtrolled by the CTE.
Eventually we may use both PID’s cross track and pure persuit, At the moment we are still learning and a combo could be one step to far