That’s incredible! Great work! Once I get a machine I’ll have to make one of these!
I get the desire to have X Y and Z and even A on a DRO, but I can’t fathom how to make good logic of the A and B axis readouts combined.
It seems like a B axis move would kind of ruin the knowledge of the positions of the other axis?
Maybe I’m not thinking right…
–Matthew Schroeder
That’s the kinematic calculations. The post(at least in NX) knows the distance from center of B axis to center of A axis then it just some highschool maths to work out the rest.
The DRO I made is reading the values from the machine itself.
Cheers
TP
Got the RPI camera up and running, streaming the work area now. The DRO is now mounted on a small tripod so it can be positioned or raised/lowered as needed. It’s become quite the exercise in many aspects. 
This looks awesome. I’m getting my machine prob next week should be here!
I’ve made some significat changes to the homebrew DRO.
I’ve updated the script to properly subscribe to the websocket to get correct display update performance. I also optimised the coordinate routines. I’ve added a program timing function by activating the second toggle switch on the side of the case. With the 2nd switch up it displays normal coordinate mode that can display position(up) or disance to go(down). When the 2nd switch is down it changes the display to show various machine times. When the 2nd switch is toggled down the 1st switch will behave as a timer reset.
Timer Mode (Switch 2 DOWN):
If anybody is interested in this project please reach out I’ll be happy to help.
DRO_V4_README.md (4.9 KB)
dro_v4.py (7.4 KB)
DRO_V4_QUICKSTART.md (6.0 KB)
DRO_V4_WIRING.md (6.2 KB)
Regards
TP