Uploaded March 2019 | Updated September 2026, 1 week ago
This is part 2 of my 3D printed robot arm. You can watch part 1 at youtube.com/watch?v=tEbJV32GyYU in case you missed it.
For the data below, it is now mostly obsolete. You should use the info in Part 3.
The CAD design of the extended wrist cap with the electronics inside is available at gallery.autodesk.com/fusion360/projects/robot-arm-esp32-drv8825-actuator-controller
The PCB Eagle Board design is available at github.com/chilipeppr/robot-actuator-controller-v1 as well as the Lua code that I used to test the actuators in this video. The NodeMCU.bin firmware is there too. This has the latest release of the firmware plus the stepper library built in. Just flash NodeMCU.bin via esptool to your ESP32 board.
The ChiliPeppr ESP32 for Lua Workspace was used to program the board and is available at chilipeppr.com/esp32
Video on how to use the ESP32 for Lua workspace to upload firmware and Lua code on your ESP32. youtube.com/watch?v=njAeHfoVIoY
Jeff Kerr's (LoboCNC) original 3D printed robot arm design is on Printables: printables.com/model/132260-we-r24-six-axis-robot-arm or Thingiverse: thingiverse.com/thing:3327968
PCB Components
ESP32 Wemos $8 (Many ESP32 devices are cheaper, but this is the smallest size broadly available to fit inside the small actuators)
aliexpress.com/item/ESP32-wemos-ESP32-WiFi-Modules-Bluetooth-Dual-ESP-32-ESP-32S-ESP8266/32815190965.html
DRV8825 Stepper Board $0.95
aliexpress.com/item/5pcs-lot-3D-Printer-Stepstick-Drv8825-Stepper-Motor-Driver-Reprap-4-PCB-Board-Free-shipping-replace/32514641632.html
DC to DC Converter $0.90 (Pick the 5V version, not 3.3V)
aliexpress.com/item/DC-DC-Power-Supply-Module-Step-Down-3A-output-24V-12V-to-5V-3-3V-Buck/32904709711.html
WS2812B LED $0.15 per (Choose white and WS2812B)
aliexpress.com/item/10-1000pcs-4-Pin-WS2812B-WS2812-LED-Chip-Heatsink-5V-5050-RGB-WS2811-IC-Built-in/32634454437.html
Slide Switch $0.29 for 20 pieces
aliexpress.com/item/20Pcs-Interruptor-on-off-mini-Slide-Switch-SS12D00-SS12D00G3-3pin-1P2T-2-Position-High-quality-toggle/32964400942.html
Screw Terminal
aliexpress.com/item/20-pcs-2-Pin-Screw-blue-green-PCB-Terminal-Block-Connector-5mm-Pitch/32814618602.html
26AWG Silicone Ultra Flexible Wire for 24v (Use 2 of the 4 wires)
aliexpress.com/item/2metre-26AWG-28AWG-30AWG-Silicone-Wire-Ultra-Flexiable-Test-Line-3P-4P-6P-0-08mm-Tinned/32870367030.html
This is part 2 of my 3D printed robot arm. You can watch part 1 at youtube.com/watch?v=tEbJV32GyYU in case you missed it.
For the data below, it is now mostly obsolete. You should use the info in Part 3.
The CAD design of the extended wrist cap with the electronics inside is available at gallery.autodesk.com/fusion360/projects/robot-arm-esp32-drv8825-actuator-controller
The PCB Eagle Board design is available at github.com/chilipeppr/robot-actuator-controller-v1 as well as the Lua code that I used to test the actuators in this video. The NodeMCU.bin firmware is there too. This has the latest release of the firmware plus the stepper library built in. Just flash NodeMCU.bin via esptool to your ESP32 board.
The ChiliPeppr ESP32 for Lua Workspace was used to program the board and is available at chilipeppr.com/esp32
Video on how to use the ESP32 for Lua workspace to upload firmware and Lua code on your ESP32. youtube.com/watch?v=njAeHfoVIoY
Jeff Kerr's (LoboCNC) original 3D printed robot arm design is on Printables: printables.com/model/132260-we-r24-six-axis-robot-arm or Thingiverse: thingiverse.com/thing:3327968
PCB Components
ESP32 Wemos $8 (Many ESP32 devices are cheaper, but this is the smallest size broadly available to fit inside the small actuators)
aliexpress.com/item/ESP32-wemos-ESP32-WiFi-Modules-Bluetooth-Dual-ESP-32-ESP-32S-ESP8266/32815190965.html
DRV8825 Stepper Board $0.95
aliexpress.com/item/5pcs-lot-3D-Printer-Stepstick-Drv8825-Stepper-Motor-Driver-Reprap-4-PCB-Board-Free-shipping-replace/32514641632.html
DC to DC Converter $0.90 (Pick the 5V version, not 3.3V)
aliexpress.com/item/DC-DC-Power-Supply-Module-Step-Down-3A-output-24V-12V-to-5V-3-3V-Buck/32904709711.html
WS2812B LED $0.15 per (Choose white and WS2812B)
aliexpress.com/item/10-1000pcs-4-Pin-WS2812B-WS2812-LED-Chip-Heatsink-5V-5050-RGB-WS2811-IC-Built-in/32634454437.html
Slide Switch $0.29 for 20 pieces
aliexpress.com/item/20Pcs-Interruptor-on-off-mini-Slide-Switch-SS12D00-SS12D00G3-3pin-1P2T-2-Position-High-quality-toggle/32964400942.html
Screw Terminal
aliexpress.com/item/20-pcs-2-Pin-Screw-blue-green-PCB-Terminal-Block-Connector-5mm-Pitch/32814618602.html
26AWG Silicone Ultra Flexible Wire for 24v (Use 2 of the 4 wires)
aliexpress.com/item/2metre-26AWG-28AWG-30AWG-Silicone-Wire-Ultra-Flexiable-Test-Line-3P-4P-6P-0-08mm-Tinned/32870367030.html
