Replies to This Discussion

Permalink Reply by Greg Fletcher on September 12, 2011 at 8:05pm

I have an idea. Get an old LP record turntable and replace the motor with a small 3 phase motor(low kv) with a controller that can be set to RPM mode. Turn table has rotational inertia due to its mass, their job is to run steady. You also have a big platter to attach test subject and equipment to, just keep it balanced. Control the PWM to the motor contoller using an Arduino controller and calibrate it. I wrote a motor controller for testing motor thrust and it works very well. I used a serial display from Sparkfun and a few switches for setting output. I can give you the code after I add the calibration setting you will probably want.

Now where to find a small 3 ph motor and RPM contoller with PWM inputs?????

Or were to get a good turn table cheap that you can hack.

• ▶ Reply

DeveloperPermalink Reply by jasonshort on September 12, 2011 at 9:36pm

Pat from Invensense was using a turntable and a USB slip ring.

• ▶ Reply

ModeratorPermalink Reply by wayne garris on September 12, 2011 at 10:11pm

turntable. seems like a good idea. will have to get my hands on one. was planing on useing zigbee for com. so, what is the best way to get an uber accurate measure of the turntables rpm? ive seen high end turntables with optical encoders on the side .a good DJ would need high accuracy on the rpms to get good sound.
thanks for the tip!

• ▶ Reply