February 2, 2008 - Light On His Feet...?

OK, so, I only promised like a month ago to show you RD-22 on his feet. Then I got sidetracked on the dome and the inner feet. Well, the long wait is over...

The two main legs were already attached, and really stable. I ended up MacGyver'ing a third leg solution for now. I already had the third leg set up, but wasn't convinced that I was going to be able to (or want to) try out a two-three-two solution, where the third moved up and down with motors and such. My thought was that, for the most part, Ardee would be a cool prop (static) droid. When I needed to drive him around (after I get past the whole radio-controlled part), I could attach the third leg at that time. The question then became... how to attach the third leg in such a way that it was easy to put on and take off, while remaining sturdy enough to handle the weight of the droid and the rigors of being driven around?

My initial thought was to use a piece of 2"x8" plank as the primary support. I cut out a hole that matched the dimensions of the center leg, and screwed the plank into the base of the frame. Then, I simply slid the center leg up through the hole. As described by the R2Builders club, I stood the droid upright on two legs, and let the center leg drop to the ground. This is the distance that the center leg should "come out" of the body. I then tipped the body forward and let the droid's weight hold the center leg in place. As you can see in the image below, Ardee's third leg is anything but stable, since it's cock-eyed.

I figured that a couple pieces of angled steel could then be attached to the center leg and then U-bolted to the pipes that support the outer legs. The center leg was still cock-eyed, and tended to slip around in the body when I moved the whole droid around the garage floor. So, in order to shore the whole thing up, I drilled two holes all the way through the center leg, where the leg started to go up through the plank. I then shoved a couple of 3/8-inch bolts through each hole, facing in opposite directions. I drilled the holes a little higher than the point where the leg met the plank, and then notched the plank where the bolts stuck out from the leg. In this way, when the center leg is installed, the bolts will fit into the notches, securing the center from twisting in the body. The angled steel then connects to the pipes, making the entire droid really stable on his three feet.

With the legs all attached and the dome in place, it's beginning to look a lot like RD-22!

Next time, I will have (hopefully) received some dome parts, and can show some more progress on the head. I also ordered the shoulder hubs to cover up the holes in the legs. The battery boxes have been covered in Bondo and primed, so they might be done soon, too.

Bob
February 2, 2008