Zaber Sinusoidal Move

[Jess_I]

Hi all,

I'm brand new to LabView and trying to adjust the sinusoidal motion of Zaber X-MCC controlled linear actuators based on load cell feedback. We expect the material being tested to creep some over the course of the test and thus the offset of the sine wave to not be constant. We would like to adjust both the amplitude of the sinusoidal movement as well as the offset based on the PID control of the force output. Is it possible to adjust this offset without interrupting the sinusoidal move command? It doesn't seem to be an option within the Zaber A Series Sinusoidal Move VI.

Thanks for your help.

[zabercs]

Hi Jess,

You're correct. The sinusoidal movement firmware function doesn't allow a changing offset or magnitude. It only allows you to specify a fixed amplitude and period. 

For more advanced movements, you may want to look at the 'PVT' movement mode. There aren't subVIs for this in the Zaber library, but the low level 'Send Command' subVI can be used to send them. This control mode allows you to set the position and velocity you'd like the axes to be at in a certain time frame. It's easy to use this for semi-sinusoidal motion by specifying consistent periods where the stage should be at 0 velocity (i.e. a peak or trough of the sinusoid) and varying the position.

Note that this mode isn't extremely responsive, as the expectation is that you are queuing the motions to do in advance (since the trajectory generator needs the information on what to do next to plan the current motion). 

Hopefully this helps. Feel free to email me directly with any questions on this.

Mike McDonald

Zaber Technologies

mike@zaber.com