No acceleration on Z axis in Helical Arc Move?

[Jeff_A]

Hello-

I'm using the Motion Assitant's Arc Move functions to create an helical motion, X/Y arc and Z linear.

When I plot the resulting postion arrrys it appears that the Z axis is not using the motion contraints (motion is linear with no ramps).

I've plotted a 3D move using a Straight Line Move and it shows acceleration (as you would expect).

I've attached modified versions of the Arc and Stragiht Line move examples - position plots highlighted..

Any thoughts on how to get proper accelerations out of the Z axis for an arc move?

[nikale]

Hi,

I'm a bit confused on your goal. You mentioned that you're trying to create a helical motion, X/Y arc and Z linear; it seems that the Arc Move.vi attached is demonstrating that. Could you elaborate a bit on what you mean by the proper accelerations out of the Z axis as well? 

Kale W. 

Applications Engineer
National Instruments
http://www.ni.com/support

[Jeff_A]

Yeah, my bad - I was confusing the curved X vs Time with the acceleration - the curve is obviously a sineusoid which is what you would expect from a circle.

The Z is linear as you would also expect.  Switching the plots to Acceleration (which I thought I had set) shows the accelartion in X/Y and Z.

One follow on question though - how do you use the Motion Assistant VI's exactly?

I have the profiles that I want but not sure how to input them into the 73xx motion hardware, confused with what to do with the result of these VI's - how to get them into the motion hardware..

If you create an LabView VI from Motion Assitant it doesn't use the "MA" VI's from the Motion Assitant sub-menu, it appears to create everyting using traditional flexmotion subvi's.

[nikale]

Hey, not a problem glad it got figured out. In regards to using the Motion Assistant VI I've attached some links below as agood starting points.

Motion Assistant:
http://sine.ni.com/psp/app/doc/p/id/psp-489/lang/en

Fundamentals of Motion Control:

http://www.ni.com/white-paper/3367/en/

I hope this helps, good luck!

Kale W. 

Applications Engineer
National Instruments
http://www.ni.com/support