Thanks to 3D printing and inexpensive controllers, a robot arm doesn’t need to break the bank anymore. Case in point? [Build Some Stuff] did a good-looking compact arm with servos for under $60. The arm uses an interesting control mechanism, too.
Instead of the traditional joystick, the arm has a miniature arm with potentiometers at each joint instead of motors. By moving the model arm to different positions, the main arm will mimic your motions. It is similar to old control systems using a synchro (sometimes called a selsyn), but uses potentiometers and servo motors.
An Arduino handles reading the potentiometers and driving the servos. Still, we couldn’t help but think you could forego the controller and simply use the pots to generate pulses directly for the servo motors — maybe use a 555. Of course, having an Arduino means more flexibility in the long run, so it makes sense to include it.
Of course, servo motor arms aren’t usually good for big jobs, but as a demonstrator, it works well, and you can’t complain about the price tag. Wow, building a robot arm is easier than it used to be. If you prefer a more conventional controller, there are, of course, many options.
10 thoughts on “$60 Robot Arm Is Compact”
video of the arm in action reminds me of 1930s king kong stop motion animation.
I think it’s the servo steps part on the mimic joystick.
The “ServoEasing” library in Arduino-land does a decent job of smoothing out servo motion. Looks like he just used the basic Adafruit library so a little bit of tweaking could probably help a lot. The closed loop between reading the pots and setting the servo positions is a little naïve too.
Nice that this control is used again. It’s sad that this simple control with a model and potentiometers is not used more. All earth moving machinery would be way simpler to use.
human limb augmentation would also be far easier to achieve using this method and some feedback.
Mechs here we come…
It remember me the one i do in 2008 ;)
No affordable 3D printer at this time , so everything is hand made :)
Nice work., Darth. How much time did you spend in the making?
It was like 2 to 3 month , but i just worked on it after work ;)
Simpler to learn, but usually not very ergonomic when used for whole day.
Are there plans available to download for this particular build such as 3D print and Sketch files?
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