Flutterby™! : User needs 2002-12-13 19:04:24+00

User needs

2002-12-13 19:04:24+00 by Dan Lyke 6 comments

Once again I find myself wondering if companies understand customers. I'm searching for some motion control solutions. I want to be able to rotate a 50-100 lb load, probably no faster than 8 RPM or so, and stop it at 30° or 45° increments. We're moving to motion control over a straight motor, with an indexing pin and a cut disk for location control because we want faster rotation to each steps, and the "pin out, motor on, wait for pin to spring back in" control we have now jerks the load too much on start and stop to go any faster. So I Google on various options, and find lots of people willing to sell me the components, usually listed by part number or product line, and a few folks willing to break it down to extremely accurate (but way overpowered for my needs) numbers, like Kollmorgen, but it'd be really nice to go to a page and see "If you want to do applications like X, then look at this product line". It's a complaint I've made before, and we're even willing to pay some conslutting fees to have someone fix this for us, but if you're trying to sell something to me then your product line names mean nothing to me; let's start with applications.

I'll dig a bit deeper. Still having some of the same "I want to search by capability, not product number" problem there.

Compumotor has their iBE Series motors which look perfect, except that they're an order of magnitude more expensive than I wanted. Of course the other thing I have to look at is that we're currently doing a 1/1500 gear reduction, so I could probably use some teeny tiny hobbiest stepper motor and still get acceptable torque if we can spin the motor fast enough.

Looking a bit further, I find that I really need someone who's got some experience with these things, there are a whole bunch of experience issues, especially surrounding gearing, that I can see running into.

Larry, if this up your alley for a few bucks I'll toss your name into the mix. I'll get resistance because after some recent troubles with suppliers in Hong Kong and New York the general attitude is to find a supplier close enough that we can walk over carrying the baseball bats when we have problems.

Yeah. The problem with looking for products indexed by application is that the applications are too broad. This is where an engineering background helps. You want to be able to take your requirements and figure out the specs for the motor...

The Kollmorgens were cool five years ago. The amount control built in to their motors is amazing. It's designed so you can basically replace a series of cams with a little code. You could get amazing acceleration but you also had control over the acceleration - and even jerk. But I never played with any as small as Dan needs...

Do the Allen-Bradleys require a Windows PC to run? I thought AB was moving their entire line to NT controlled devices.

A-B builds hardware while Rockwell Software builds software applications that work with A-B and other contrllers. Rockwell Software is a Microsoft shop. All software they produce for running on a PC is going to require NT 4, at least, to run under. A-B is building their controllers for interoperability with any platform that someone is willing to put the resources into building the software for. They will publish their communications protocols and their APIs and sell their SDKs to anyone. Even Rockwell Software is committed to OPC and a dozen other methods for moving data between platforms.

Now to actually answer that last question, a drive doesn't require a PC or a Mac or a *nix box to run. They can be programmed with a keypad called a HIM. They can also be controlled from a PLC. Rockwell Software build software applications that also communicate with the A-B drives and those applications run under Microsoft OSes but their protocols are generally open enough that you can write your own application if you'd like that runs on any OS. You can even use Perl if you'd like.