Hi,
disclaimer: tho I consider myself pretty good at coding, by no means I'm at least mid what comes to hardware designs, this project will be learning experience for me, so please hold back your cringe
A bit of background:
I purchased this old used sit/stand desk few months ago. While I was moving I left it overnight in around 0 C temp, I know, showing my genius right from the start, it died, at least partially - going down, but no up and sizzling.
It only had "UP/DOWN" buttons, no memory ect., when I bought it I already had in mind that I will add more features.
Features I will add:
1. few memory buttons (capacitive touch buttons or touchscreen)
2. some sort of display (LCD or segment) with hight output (time of flight sensor), clock and other stuff I will think off.
3. wireless control (wifi, BT or RF)
4. optionally - communication directly to my workstation via USB (will make sense later...)
All UI elements will be hooked via I2C (CJMCU-2317) or/and SPI so I don't have to worry about extra pins for additional UI.
Currently I'm working on boring stuff: remaking power supply and motor control circuit, I had to remake them because old board had way too many power lines and was too complicated to add Arduino compatible MCU plus it's broken, remember?
Also I wanted motors power supply to be off, only keep MCU alive.
The victim, isn't she a beauty, 200x100cm, solid as rock:
My loose "concept".... ata ta ta ta shut it, it's over 10 years photoshop skills!
(not all components included):
High voltage circuit layout in 3D:
High voltage circuit on purfboard (read first sentence!
I split breadboard and removed unused dots where needed to prevent shorts):
Installed (huge attention to details, just look at that captain tape on relays, no more fire or shock hazard at all, told ya, real pro at work
):
Low voltage board WIP:
I'm still working on it, I'm having problems stepping down transformer voltage (50V) to motor voltage (24V), mosfet that should do this keeps dying (no pop or magic smoke!
), there is reversed voltage polarity diods. I ordered more beefy mosfets (hope they will pop or smoke
), so hope to fix this issue when it's here, for now I'm continue working on legs: actuators limit switches, rotary encoders, time of flight sensor, will post more details about them tomorrow...