# specing/buying a less-expensive 150W servo motor/controller

J

#### Josh

Hi,
I'm wondering where I can find a low-cost servo/driver/controller setup for the following application:

I want to build a linear actuator to adjust the distance of my monitors on my desk. I usually sit with them about 6 feet away, but it'd be fun to be able to adjust that, controllable from my computer.

So the spec I'm looking at is a servo to position a 30Kg load over a range of 2 meters. I'd like it to be able to move from end-to-end in at most 2 seconds. According to my rusty physics, that requires about 60 Watts of power, so I figure bumping that to 150W to account for inefficiencies in energy conversion.

I intend to drive this from my computer, but it'd be nice if it also had the ability to function in a standalone mode via an analog input that specified velocity. I'm imagining having a switch on my desk as a 'manual override' that enables a simple throttle level/joystick.

The best pricing I can find so far is around $700:$400 for the driver/controller from jrkerr.com
$50 for the motor from easymotioncontrol.com maybe$100 for a power supply, maybe from u.s. digital?
maybe $100 for an encoder from where? Anyone have recommendations for recommended parts or places to buy them? Thanks! Josh K #### Ken Emmons Jr. Try using DC motor with leadscrew for custom car audio applications. You can get them for about$150 and they should give decent force. Also look
at surplus electronics stores they carry that kind of thing sometimes.

~Ken