drive for actuator

[st_syd]

hi,
i need to drive an actuator containing a dc brush motor. i need to be able to drive it in both directions (forward and backward)
its spec's are, voltage input of +- 12Vdc, and module circuit currect of 25mA(max), though i think the current rating is wrong. i called up the manufacturer and he said they had no specific info on this actuator. The actuator is actually a slave actuator from an automatic car door locking system. i believe the current reqcuired is more near 2A.

so the drive that i require will not need to be too powerful

could you recommend a drive for this, either ni or third party which i can link to my daq board (PCI 6014 placed inside a BNC 2010). i am thinking of not using a controller. my feeback wil come from an LVDT linked into my daq board. The control will come from my labview application.

thankyou.

[VGA_CD-ROM]

Hi sri_86,
Did you mean you were connecting the DAQ 6014 to a BNC-2110?

Unfortunately, NI does not sell any drives which will be within the compatible voltage ranges of your actuator. And your 6014 card is limited to +/- 10V, so you'd have to find a drive which could linearly amplify your signal to +/- 12V.

Your best option from what we offer is to instead use  a SoftMotion-based system with a cRIO/cDAQ 9505 which can be placed in a CompactRIO or CompactDAQ chassis and programmed in LabVIEW. This would let you choose your operating voltage by supplying the 9505 with a 12V source, and you could also perform trajectory generation, stepper generation, spline generation, PID Control Loop, and encoder feedback. Some of those features require the LabVIEW Real-Time module, the LabVIEW FPGA module, or both.

However, if your actuator only operates in an ON/OFF state (after all, car door locks typically only go all the way forward/up and all the way backward/down), then it may only require a +12V signal to go to the end in one direction and then -12V to go to the opposite end. If that's the case, you would probably only need to set up a +/- 12V relay system that you could turn on or off (i.e. control closing or opening the relays to provide current to the actuator) using your DAQ. Then you would only need to do simple digital I/O signaling through your DAQ  in LabVIEW to a relay which operates on TTL 0-5V logic, and then hook it up to a +/- 12V sourcing setup.

[st_syd]

hey,

thanks for the reply.

i am thinking of using the ni 9505. As you said this can be used as the drive and can be programmed to be used as the controller.
i have labview 7.1 student version and the control design and simulation module.
is this enough to do the programming or do i need other software modules? i am not going to embed anything into the ni 9505.

i am only going to do pid control, with the voltage from an lvdt as feedback. i am not going to do spline generation and the like.

thanks



Message Edited by st syd on 04-14-2008 11:23 PM

[VGA_CD-ROM]

Hi st styd,
I misspoke earlier - the 9505 can only be controlled through a compactRIO (cRIO) and is not deployable on a compactDAQ chassis.

I believe all you need is LabVIEW 7.1, the LabVIEW FPGA module version 7.1 (needed to target the 9505), the 9505, a cRIO controller and cRIO chassis to place the 9505 in, and a 12V power supply to provide a reference for the 9505. While the PID toolkit would add a PID VI for the FPGA, the one provided by SoftMotion has improved PID algorithms specially tuned to the 9505 and it really your better option. Using the SoftMotion PID VIs also requires the LabVIEW Real-Time module.

The only version of LabVIEW FPGA we currently sell is the latest version, 8.5, and it only supports LabVIEW 8.5. Having a subscription to the NI Developer Suite would keep you up to date with all the latest versions of LabVIEW, the FPGA and Real-Time Modules, the PID toolkit, and lots of other associated software.