Homing Direction
I have a problem with my AR3 arm when it comes to homing
Specs:
AR3 Aluminium build
External encoders
Teensy 4.1
Teensy sketch 3.0
AR4 HMI 4.4
Running MK4 defaults
At rest before homing
J1 Dir 0v
J2 Dir 3.2v
J3 Dir 3.2v
J4 Dir 0v
J5 Dir 3.2v
J6 Dir 0v
When I home the axis, they all seem to home to the negative direction, for example J6 will home to the negative, if I change either of the motor direction or the home direction (hit save) it will still home to the negative.
However when I jog the axis, negative moves to the negative and positive moves to the positive.
This appears to be the same for all of the axis (haven't checked J5)
I have also tried loading teensy sketch 2.0 and AR4 HMI 1.3 (last known good) and have the same issue
Any ideas where I might be going wrong?
(2years ago when it was being used it was fine)
Thanks Chris
Directions are correct from the manual when jogging all of the axis, but not for homing.
Drivers checked, dip switches are as per the manual.
I've reseated all of the wires in the teensy and driver.
Tried all of the defaults on the kinematics tab, also the Directions and homing directions.
Could it be an encoder issue? Ie it's only reading one way, so when it starts to home, it's causing the confusion.
I've tried to run the encoder test, but I've run out of screen size on my 1366x 720 laptop
Dan
3 replies
Chris Annin
If you are running the latest software but your robot was an initial AR4 build I would use the MK1 default setting on the kinematics tab. If rolling back to sketch 2.0 and you are having direction issues I would first verify from the manual that the + and - directions are correct per the diagram. I would also check the drivers as the older drivers did have a direction dip switch.