Saturday, July 29, 2017

Ezevor and other robot arms


I stumbled across the Evezor Kickstarter page recently and was fascinated to see the range of things this SCARA arm can do. It can 3d print, carve or mill like a CNC machine, laser-engrave, pick and place electronic parts, paint or draw, and more. It also appears on Thingiverse.

There are Youtube videos of many of these operations. The resolution is good. The effective build volume is enormous. The speed is decent. As I watched more videos, I got a little bit obsessed with the whole thing and decided to blog about it.

The Kickstarter campaign was regrettably unsuccessful. You can still pre-order one for $2650, but I can't justify an expense like that currently, and I suspect the lead time would be substantial.

In the midst of my obsession, I started poking around the interwebs to see what other similar projects might exist, and might be more affordable as well as open source, and came across quite a few.

Several arms work like a Luxo lamp, using parallelograms along the arm segments to keep the end effector in a consistently vertical orientation.
These are all appealing for cost reasons, but I worry about the resolution. They'd be fine for picking up small objects, and maybe some drawing, but I'd be surprised if they could do 3d printing or CNC milling with a Dremel tool.

There are a couple other SCARA arms. These are more commercial and expensive, and don't appear to be open source. But for that price they probably have the resolution. I found a couple more that were neither Luxo-style nor SCARA. So if you get obsessed with the original idea of a robot arm that can do a wide range of precision tasks with a potentially heavy payload (like a router for doing CNC milling), what should you do? My own inclination would be to print parts for an Ezevor. It would be interesting to see whether either the SparkFun arm or the Tindie arm could be a serviceable 3d printer. If not, I'd probably hunt around for a larger 3d printer than the one I have at home.