I’m making a digital readout for my rotary table. I’d like to use a rotary encoder and a display to show degrees. 0-360* with no counting of full rotations.
There’s a plenty of encoders available with a variety of outputs. For my purpose, an incremental unit would be typical, but an absolute unit would also be fine. What type of output would play best with Arduino?
An incremental encoder would work but somehow it needs to be calibrated, set to zero somehow. Do You really need a waterproof encoder? That likely costs a lot extra.
I’ve built a similar device but with a stepper doing the cranking. Steps per rev or angle step can be set. The resolution is 576 000 steps per table rev.
More buttons can easily be used to preset any degree You want. Here only dry milling is done but great those decoders don’t empty Your wallet.
As said, incremental and either 5 volt or open collector output are easy to interface with Arduinos. Do some math deciding what encoder resolution You need. Not knowing all of them but up to 4096 steps per rev exist.
Going for an LCD having an I2C interface is recommended. Less of cables, less of controller I/O pins used. They are my favorites.
A quadrature encoder with digital A and B channels will work with standard code on any controller. No need to bother with special protocols on other interfaces
It’s a surface that rotates via hand crank and is graduated in degrees, minutes, seconds.
I use it in machining to cut curves or drill hole patterns with polar coordinates. Degrees are marked around the table and minutes, seconds on the hand crank. These can be hard to read while machining, difficult to set 0 where needed, and I’d much prefer degrees in decimal format.
Here’s the rough layout for illustration. The encoder will probably be off-center and connected to the rotating hub with a GT3 timing belt (this will get me another 3X resolution). Also possible is giving up the open center in the hub and mounting the encoder in-line.
The pictured rotary table is mine and the resolution is 10 seconds. This is at the handle, so it doesn’t pickup any play in the worm gear. The rotary encoder would read the table directly and avoid gear backlash.
