Educational Robot Arm

One of the great projects in robotics is the robotic arm and gripper (end effector to be more technical). Arms can be stationary or mounted to a movable platform on on a humanoid robot. A classic problem to solve is the "Tower of Hanoi" children's game/puzzle - you've played this one! This simple game lets you demonstrate with your arm and gripper repeatability, dexterity and program problem solving. It is a perfect learning project! 

My friend Phil (PhiPi at the Parallax Forums) recently posted a thread with this...

This coming semester, I've volunteered again to teach a robotics course at the local high school. The class of 20 students will be studying CAD and programming, beginning with ActivityBot programming in Spin. I will have 10 students on Tuesdays for an hour and a half, and the alternate ten on Thursdays for the same amount of time.

The course objective this semester is to design and program a robot arm capable of solving the Towers of Hanoi problem. (Thanks, erco, for the idea!) The CAD side will design the mechanical parts in Rhino, to be cut out on the school's laser cutter. The programmers will have to learn how to control the robot and figure out the puzzle algorithm.

I've never built or programmed a robot arm before. In order to stay a step or two ahead of the kids, I needed to do that -- pronto! So I went online and found a laser-cuttable arm design (the uArm) that uses standard servos and is free to duplicate under a Creative Commons license. In order accommodate the cheap 2.7mm meranti doorskin that I wanted to use, my own bearings and bushings, the Activity Board, and my own gripper design, I needed to make a considerable number of mods to the uArm patterns.

Here is video of the (practically) finished product:

Great work as always Phil! What a fun project.

My pal Eric (erco at the Parallax Forums) loves to look for ways (like most engineers) to do the most with the least. This is also great for students, those on a budget, and those with our very sophisticated tools. Here are couple of his solutions (the latest version is shown first followed by an earlier version) - Remember - same problem - same challenges - different approach! This is what is so much fun about robotics!

I wanted to record this work for future reference. What neat solutions!