Re: Servo Control - C#?

Time to Google.

USB-to-serial dongles appear to your PC (or laptop) as a serial port.
You write your code to that port. You'll need Framework 2.0 or later
unless you're okay with using an ActiveX control for the serial output.
What you hang on the dongle is up to you. A serial servo controller
works just fine; however there are ready-made USB servo controllers that
do this all-in-one so you save money. Parallax sells one such
controller. I've not used it but I've seen some C# code for it in the
Parallax forums. It's about 40 bucks.

Read up on servo control. Most people get this wrong and try to apply a
continuous stream of pulses, which is easy in the typical D/A card, and
is standard for PWM. That won't work with an R/C servo, which is not a
true PWM device. You need to put in delays between in each single pulse.
The nominal delay is 20ms. Your card may or may not have this feature,
but it seems a waste anyway when low-cost hardware (serial or USB servo
controllers) is available that will do it set-and-forget.

-- Gordon


c83k2@xxxxxx wrote:
First post on the group. Finishing up a PhD and I have been doing a
lot of instrument control the past few years through .NET applications
- C# primarily and recently became interested in a little side project
that would involve a tilt-pan servo controlled from the same. 2 Servos
only.

I have absolutely zero experience dealing with Servos. GPIB, D/A, A/D
- I've got it clocked, but this is new territory for me. Overall it
seems most servos are controlled by pulse length to determine angle of
turn. That's fine - I can generate those from my desktop NI D/A cards.

But I'm looking at looking at working from a laptop.

Any reccomends on a pre-packaged USB interface that I can address
through the C# applications? I'd be willing to spend some money if an
accessory was available that streamlined my .NET control. I would
rather focus on code than troubleshooting a baseline device I don't
fully understand.

I see something like this at ServoCity - http://www.servocity.com/html/pc_servo_programmer.html
. Are these usually bundled with .NET libs? Or do you just use
standard serial interface libraries?

I'm completely ignorant. Any help is appreciated.
.

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