How can I start two motors at different velocities and different distances (steps) at the same time?

[tochuck123]

I've been using the Motion package and Labview 7.0.

I have 3 stepper motors to control and much of it is done individually.

However now I want to control 2 of the motors at the same time.

I was looking into vector spaces but the two motors have to turn at different rates

and a different number of steps.  It doesn't appear as though vector spaces are

the way to go for this, but I'm not sure how to ensure the two motors will start

at the same time.

Thanks

Chuck.

[Jochen]

Chuck,

vector spaces are used whenever you need to perform coordinated 2D or 3D moves. In a vector space all axes start and stop at the same time. E. g. in case of a linear 2D vector move you only need to load velocity and acceleration values for the resulting 2D vector. The driver and the board take care that a straight move is performed from the start position (X0, Y0) to the target position (X1, Y1).

If you don't need this type of synchronisation then you won't have to use a vector space. If you only need to start axes simultaneously "Start Motion.flx" will do. Here is a paragraph from the online help:

"The Start Motion VI is used to start a motion profile on axes or vector spaces, either simultaneously or individually. A start is preemptive and uses the most recently loaded values of acceleration, velocity, target position, s-curve, operation mode, and so on to generate the motion profile."

Use the Axis/VS Map parameter to define the axes that need to be started at the same time.
I hope that helps,

Jochen Klier
National Instruments Germany

[tochuck123]

Ok so I can use the Start Motion.flx... something I was already using for single axis motion.  Do I still wire the Axis/Vector space control or just use the Axis/Vector Space map?

Thanks in advance

Chuck

[Jochen]

Chuck,

again here is a paragraph from the online help:

"To start a single axis or vector space, set the Axis or Vector Space selector to the appropriate axis or vector space. The Axis/VS Map bitmap is ignored.

To start multiple axes, the Axis or Vector Space selector is set to 0 (zero) and the Axis/VS Map bitmap defines the axes to be started. Similarly, to start multiple vector spaces, the Axis or Vector Space selector is set to 0x10 and the Axis/VS Map bitmap defines the vector spaces to be started."

Jochen Klier
National Instruments Germany