Firmware and documentation of a custom built machine that winds and cuts cable to certain lengths.
Extensive details about this project can be found on the website: pfusch.zone/cable-length-cutter

Photo of the built machine

Current Features

Measure length using rotary encoder
Wind to set length while start-button is pressed
Automatic wire cutter
Control interface:
- 2x 7-Segment display showing lengths and notifications
- Buzzer for acoustic notifications
- 4 Buttons and Potentiometer for setting the target length
- Reset and Cut Button
Stepper motor controlling a linear axis guiding the cable while winding
Store last axis position at shutdown

Usage

Electrical Details

For detailed documentation of all electrical aspects, see connection-plan.pdf.

Printed Parts

All designed and 3D-printed parts can be found in the cad/ folder. These parts were designed using FreeCAD.

Components

Custom pcb with ESP-32 microcontroller

See connection-plan.pdf

Rotary encoder LPD3806-600BM-G5-24C

- Pulses: 600 p/r (Single-phase 600 pulses /R,Two phase 4 frequency doubling to 2400 pulses)
- Power source: DC5-24V
- Shaft: 6*13mm/0.23*0.51"
- Size: 38*35.5mm/1.49*1.39"
- Output :AB 2phase output rectangular orthogonal pulse circuit, the output for the NPN open collector output type
- Maximum mechanical speed: 5000 R / min
- Response frequency: 0-20KHz
- Cable length: 1.5 meter
- size: http://domoticx.com/wp-content/uploads/2020/05/LPD3806-afmetingen.jpg
- Wires: Green = A phase, white = B phase, red = Vcc power +, black = V0

Installation

For this project ESP-IDF v4.4.4 is required (with other versions it might not compile)

#download esp-idf
yay -S esp-idf 
#alternatively clone the esp-idf repository from github and do `git checkout release/4.4`

#run installation script in installed folder
/opt/esp-idf/install.sh

Build

Set up environment

source /opt/esp-idf/export.sh

(run once per terminal)

Compile

cd board_single
idf.py build

Flash

connect FTDI programmer to board (VCC to VCC; TX to RX; RX to TX)
press REST and BOOT button
release RESET button (keep pressing boot)
run flash command:

idf.py flash

README.md

Overview