[Solved] Potential issue with Position Tuning in IONmotion
Posted: Thu Nov 12, 2015 1:36 pm
Was working with IONmotion on my Win 7 Laptop.
Decided to do comparative tuning and testing with changes to settings between my motor1 and motor2.
Roboclaw 2x15A firmware version 4.1.14
IONmotion 1.6.4
Loaded values from Roboclaw which have been working reasonably well up to now.
These values were derived from a previous running of IONmotion and simplified to rounded integers.
Speed 2000, accel/decel 3000, QPPS 2000
Position settings PID 5000,0, 32200
Set MaxPos on 5000
Selected PIV tuning on motor1 and ran the autotune. It produced some values which were reasonably similar to the original values when the level slider was moved to the left.
The strange bit occurred when I tried to move the motor1 slider down to zero, and then to the top value.
Regardless of how fast I moved the slider (fast as possible to try for smooth action) the movement of the motors was rubbish, coughing, spluttering, very slow movements etc.
BUT on the same settings Motor2 worked smoothly and quickly. Note here that I did NOT run the autotune on motor2.
Attempts to move the motor1 speed slider resulted in very slow, lumpy movement somewhat similar to what happens if you click on the slider and then use the up/down keys. About 20 clicks top to bottom but rough.
After about 20 minutes of attempting to understand what was happening and adjusting settings, I got the wonderful microsoft blue screen and ram dump.
After starting the computer again and restarting IONmotion - settings were still available and motor1 ran WELL. I am reasonably comfortable with the results obtained, but not with the strange effect on IONmotion.
I have not run the autotune function again since.
I do not have a solution but think there is something not right with the tuning system.
In addition I would like to suggest that the speed slider coding be adjusted to allow the slider to be moved fully one way or other with the mouse button held down, and that no motion be initiated until the mouse button is released. That way we can easily get some meaningful movement curves.
I am finding that I get much simpler control by just changing the MaxPos value from 500 to 5000 to 500 etc.
Result is nice clean movement between 250 and 2500 without touching the slider at all. Nice graphs using setpoint and position lines.
This technique usually requires manually moving the speed slider down to the bottom first to 'prime the pump' then changing the MaxPos usually will work. Clicking away from the slider to do something else usually means moving the speed slider down to the bottom again.
Decided to do comparative tuning and testing with changes to settings between my motor1 and motor2.
Roboclaw 2x15A firmware version 4.1.14
IONmotion 1.6.4
Loaded values from Roboclaw which have been working reasonably well up to now.
These values were derived from a previous running of IONmotion and simplified to rounded integers.
Speed 2000, accel/decel 3000, QPPS 2000
Position settings PID 5000,0, 32200
Set MaxPos on 5000
Selected PIV tuning on motor1 and ran the autotune. It produced some values which were reasonably similar to the original values when the level slider was moved to the left.
The strange bit occurred when I tried to move the motor1 slider down to zero, and then to the top value.
Regardless of how fast I moved the slider (fast as possible to try for smooth action) the movement of the motors was rubbish, coughing, spluttering, very slow movements etc.
BUT on the same settings Motor2 worked smoothly and quickly. Note here that I did NOT run the autotune on motor2.
Attempts to move the motor1 speed slider resulted in very slow, lumpy movement somewhat similar to what happens if you click on the slider and then use the up/down keys. About 20 clicks top to bottom but rough.
After about 20 minutes of attempting to understand what was happening and adjusting settings, I got the wonderful microsoft blue screen and ram dump.
After starting the computer again and restarting IONmotion - settings were still available and motor1 ran WELL. I am reasonably comfortable with the results obtained, but not with the strange effect on IONmotion.
I have not run the autotune function again since.
I do not have a solution but think there is something not right with the tuning system.
In addition I would like to suggest that the speed slider coding be adjusted to allow the slider to be moved fully one way or other with the mouse button held down, and that no motion be initiated until the mouse button is released. That way we can easily get some meaningful movement curves.
I am finding that I get much simpler control by just changing the MaxPos value from 500 to 5000 to 500 etc.
Result is nice clean movement between 250 and 2500 without touching the slider at all. Nice graphs using setpoint and position lines.
This technique usually requires manually moving the speed slider down to the bottom first to 'prime the pump' then changing the MaxPos usually will work. Clicking away from the slider to do something else usually means moving the speed slider down to the bottom again.