Desktop Robotic Arm
Instructions
Intro
This is a desktop robotic arm powered by hobby servos. It's quite powerful, it can lift up to 500g and is relatively precise, depending on the quality of the servos used. It's a fun project to try for about $100. The picture has a list of materials ued and some orientative prices. The may vary on your region.
Estimated time: 1 minutes
Cut the parts in the X-Carve
Cur the parts in the X-Carve as per the linked Easel project. I used a straight bit and increased the recommend pass depth from 1.3 to 2.5mm, leaving the suggested feed rate of 1016mm/min. Being soft plywood, the machine should handle it without issue (I usually cut mine at 5mm per pass, but my CNC is not X-Carve). After cutting, clear and sand the tabs on all parts, move to assembling.
Estimated time: 60 minutes
Assembly - base
Look at the pictures for parts involved. The servo will hold everything together. Remove the servo output wheel from the motor, then screw it to the bottom piece. Now screw the motor to the top part. Finally, put everything together like in the picture, and add the screw that attaches the servo output wheel with the motor.
The 8x22mm bearings are just put in place and can move freely within the wooden channels. If you feel like so, you can use some 8mm screws to attach them to the middle part, but it may require some tweaking of the channels in the top and bottom pieces.
Estimated time: 20 minutes
Assembly - Body
TBD
Estimated time: 20 minutes
Assembly - Arm
TBD
Estimated time: 30 minutes
Assembly - effector
TBD
Estimated time: 20 minutes
Electronics
For the electronics, you can use any Arduino servo shield. I have also included a Fritzing file (ArduinoNanoShield-31mm.fzz) with a smaller board that fits with an Arduino Nano inside the robotic arm itself, but you can use just any servo shield. Milling the board in your X-Carve is definitelly possible and should be an easy project, it's just a one-sided board with few tracks and holes.
The default firmware comes configured to connect the servos to these pins:
Left motor (looking from behind the robot): pin 10 Right Motor: pin 11 Rotation (base) motor: pin 3 Effector (tip) motor: pin 5
You can also use "hacked" servos to read of the servo potentiometer and connect them to analog pins in the arduino (google "servo read potentiometer arduino"). These pins would be:
Left motor: analog pin 3 Right motor: analog pin 1 Rotation motor: analog pin 2
All these pins can be configured in the Firmware before deploying to the arduino in the file MyArm.cpp, check the instructions in the Github repo in the next step.
Estimated time: 30 minutes
Software
The software to control the robot can be found on GitHub:
https://github.com/dsuarezv/myarmui
thre you can find all the details to install theArduino firmware and control the robot with the included GUI.
Estimated time: 30 minutes
Comments
It’s a cool project, but I don’t find the costing practical. You can buy a DIY robotic arm kit on aliexpress with the exact same motors and pieces you carved for 25 euros and your budget is set at 100 euros.
Mark Hall · June 27, 2018
Seriously, exact same? I'm buying 10!!
David Suarez · June 28, 2018
Hi there, I like the idea of using this to hold a monitor, but when I try to open it, it says that it's not shared publicly. I'd like to make this to hold a monitor for my Rpi, hope you can make this project public. -Drew
Drew · July 05, 2018
Ops, I thought it was already public. It should be now. Tell me if you have trouble accessing it.
David Suarez · July 05, 2018
So i am using a carvey to to cut some plywood. How do I tell it to do all the holes first and then cut the outside edges. Currently it cuts the shape first
Marcus Knighton · July 30, 2025