Updates on RD-3D now that he's done a few shows

The one thing I've learned as I've really gotten into the Maker Movement is that rarely does anything work right the first time. You have to keep researching, learning, testing, and trying new things.

For example: the rubber bands that I use for tires on his tiny wheels. I had the hardest time gluing the rubber bands to the wheels. I tried all different kinds of glue, even rubber cement which is nearly perfect for gluing rubber. Nothing would work. But it turns out rubber bands are coated with a special powder that keeps them from sticking to anything, even glue and rubber cement. A quick rinse under the sink and presto, the rubber band tires can now be glued to the wheel!

Another problem I had was with the front forks. I designed them in TinkerCad using measurements of the button wheel I made with my calipers. I added a little "shelf" perpendicular to the forks that fit under the lower lip of the can to keep the forks steady.

Unfortunately I measured the width of the button in the CENTER and failed to account for the outer lip of the button which is a little bit fatter. No big deal. The button-wheel I measured was actually 2 buttons glued together, so I could still use a button, I just had to use a single button rather than the double I had wanted.

But then another problem arose. RD-3D started turning while he was moving. It was as if he were steering off-course. It seems that the little "shelf" I made didn't to as good a job as stabilizing the forks as I had wanted. So, I decided to go back and redesign the forks, making them wider (to hold a double-button wheel) AND to also improve the shelf so that it would stabilize with the can better. So I greatly increased the size of the shelf and also contoured it to the curve of the can which makes it nearly impossible for it to pivot around the screw like it had been doing. So far, so good.


But there is one more issue I've been dealing with. The 9 v. batteries I've been using seem to go dead after just 4 shows. There is NO REASON for them to die that quickly. I mean, they aren't DEAD-dead, just low enough that RD-3D can't move. His lights still turn on and blink quite brightly, and he has enough power to do his "shaking" thing (which turned out to be one of the funnier jokes in the show).

When he's supposed to move across the table, I can hear his motor struggling, but he doesn't actually move. I think I know what the problem is, and I'll report back on it whether I'm right or wrong.

RD-3D is Finally DONE!!

It is such a relief to have him all completed and know that he works like I want him to. Everything he does is programmable. That is, I can adjust how long the lights are on and off, how fast and how far he moves forward and backward. But it's all programmed BEFORE the show; sort of like how I memorize lines, RD-3D will have "memorized" things he will do.

For example, I'll ask him questions and the green light will represent "yes" and the red light will be "no." But he won't actually hear the questions, just wait a set amount of time and then turn on the green light for a second. Also, the shaking back and forth he does near the end of the video I think I'm going to use as a joke in the show. I'll say something like "Okay, we have an agreement. Let's shake on it," and he will begin to shake.

Foundations of a Robot Puppet

While in my local Lakeshore Learning teacher supply store I spotted this little toy on a discount shelf and snapped it up. I "knew" I wouldn't use it (i.e. "thought" I wouldn't use it), but figured it might provide some inspiration for my own robot project.

Little did I know that it would become the basis of my show this summer!

First of all, this is a toy, and certainly NOT a robot. From an electronic standpoint it is a simple circuit with a switch, battery, and a motor; turn on the switch and it completes the circuit causing the motor to run until you turn it off.

But I liked two thing about it that I wanted to use: 1) The frame that holds the can, and 2) the gear exchange that uses the motor to drive the wheels.

But I wanted to wire it to an Arduino so that I could control various aspects of the motor. I wanted to be able to go forward AND backward. I wanted to be able to control the SPEED of the motor, and I wanted to be able to time certain things to happen (move forward for 2 seconds then stop for 5 seconds, then go backwards at half speed for 2 seconds, etc.).

Anyway, I have been playing with it. I am unsure of what I'll be able to do, but I was happy to notice that 10 oz. cans (most soup cans, Rotel tomatoes, etc) are about the same size as soda cans and will fit within the frame of this robot.

The downside is that I knew that one can would not be big enough to hold my Arduino and all the wires I might need for the LEDs, moving arms, etc. So I carefully measured the inner diameter of a 10 oz. can, got on Tinkercad and fabricated this "Tin Can Connector."

I'm not going to lie to you. This was very simple to create...and I still felt like a freaking ROCK STAR when I finished! And even MORE like a rock star when I picked it up from my local library (thank you Friendswood Public Library for being so amazing!!).

I'm even more inspired now than ever before about this summer's show. We live in an amazing time where we can sit at a computer, imagine something, design it, email that file to our local library, and for pennies per gram, pick up a perfect rendition of our imagination come to fruition.

I'm not mechanically inclined and never have been. So, when I tell you I'm nervous about finishing this project, it is true. But this first step was so surprisingly easy, that my confidence has been renewed. For a long time I kept thinking I should just BUY a robot that does what I need and be done with it. But I just couldn't bring myself to do a show about MAKING things while refusing to even TRY. So, if this doesn't end up in the show this summer, know that it wasn't for lack of TRYING!!