TinyCircuits Forum

General Category => New Product Ideas => Topic started by: oronymo on May 22, 2014, 02:30:41 PM

Title: Custom Servo Controller
Post by: oronymo on May 22, 2014, 02:30:41 PM

I'm trying to control a massive array of motorized faders (like these: http://www.alps.com/WebObjects/catalog.woa/E/HTML/Potentiometer/SlidePotentiometers/RSN1M/RSN1M_list.html (http://www.alps.com/WebObjects/catalog.woa/E/HTML/Potentiometer/SlidePotentiometers/RSN1M/RSN1M_list.html) ).

I'm able to control them manually by reading the analog in from the slide pot and controlling the attached DC motor with a PWM motor controller. This works fine for a few, but when you get up to 100's it starts to get really inefficient.

I'm wondering if a custom servo type IC would be the solution. Something kind of like your motor controller, but with an analog input (for the slide pot) and enough on-board smarts to use a PWM position signal to drive the motor to a specific position - basically turning the whole assembly into a standalone Servo.

Is this something that's possible? If so, our company would use about 500 of them (!)

Title: Re: Custom Servo Controller
Post by: tinybuilder on May 29, 2014, 09:10:41 AM

Perhaps a TLC5940 (http://www.ti.com/product/tlc5940). Here is a Breakout board (https://www.sparkfun.com/products/10616) from Sparkfun and a tutorial from bildr.org (http://bildr.org/2012/03/servos-tlc5940-arduino/).  Here is some additional information and Arduino Libraries. (http://playground.arduino.cc/Learning/TLC5940)

Or perhaps the PCA9685 (http://www.adafruit.com/datasheets/PCA9685.pdf). Here is the Adafruit 16-Channel 12-bit PWM/Servo Driver - I2C interface (http://www.adafruit.com/product/815) which uses it. You can even chain up 62 breakouts to control up to 992 PWM outputs! Here is a tutorial (https://learn.adafruit.com/16-channel-pwm-servo-driver) and Arduino Library (https://github.com/adafruit/Adafruit-PWM-Servo-Driver-Library).