Softmotion with M-Series DAQ?

[Murph]

I have 2 stepper motors running off of  Parker E-DC controllers and power supply. It is a master/slave situation in that the slave will be a geared ratio of the master but remain in sync. There are home, min and max limit switches.

I built an application in LV using an M-Series DAQ card but it is not very reliable and the coding was very very difficult.

I only recently learned of Softmotion and was wondering if it can be used with a DAQ card without any of the 'motion control' products that it works well with or should I consider buying something like a c9512 or something like that?

Mike

[Jochen]

Mike,

for stepper motor control you need to generate a digital pulse train including acceleration and deceleration ramps while keeping control over the position. This is quite hard to accomplish with a DAQ device and SoftMotion won't help much in this case. On a real-time system you could use a DAQ device for servo motor control (command signal = analog output, feedback signal = encoder position measurement with a counter) in combination with SoftMotion, but as already said, stepper control is difficult with such a setup.

In contrast an NI 9512 is a good solution for stepper control, but it requires a cRIO system and can't be used in a cDAQ chassis. If you are looking for a PC based solution, a board like a PCI-7332 provides good stepper performance and an easy to use API. Electronic gearing is done onboard and can be configured with a single vi/function call, so for your application it sounds like an ideal solution.

Kind regards,

Jochen Klier

National Instruments

[Murph]

Thank you. This is what I thought too and I really do want to go the cRIO route but it is up to the user.

Thanks again.