finds HOME and moves a bit more

[lmd2]

using steppers in open-loop mode, when executing a Find Home, the axis moves to home, hesitates (stops briefly), and then moves a few more degrees of rotation in the same direction (maybe at a reduced speed, but it is so small a motion that it is hard to tell). How do I get it to stop and stay stopped?
My settings are:
initial search direction:   forward
find approach direction:   forward
home edge to stop on:   forward
approach velocity:   20%
offset move:   0
Reset:   not checked
smart enable:   checked

TIA
lmd2

[Jochen]

What you see is expected and intended behavior. Find Home is not a single move but a sequence of moves. A home switch provides four positions where to stop the axis. This behavior is well documented in the NI-Motion help files.

Here is an example (copied from the NI-Motion VI Help):

As shown in the following figure, this Find Home sequence searches for the home input in the forward direction (1). When the home input is found, the reverse edge (2) is located. When the reverse edge is located, this edge is approached in the forward direction (3).

I hope that helps.
Best regards,

Jochen Klier
National Instruments Germany

Message Edited by Jochen on 08-30-2005 04:51 PM

[Giridhar_Rajan]

Hi,

Here's an example which does sequential two axis referencing as per the standard industrial machines.

[lmd2]

thank you both, my understanding of using the Find Home feature is greatly improved (previously I only worked with hard and software limits).

lmd2