Build A Robot Hand | DIY Science Time

We're gonna actually try to build a robot hand and that is a little more difficult than building an art bot because, well, hands do lots of amazing things. I can wiggle my fingers, I can pick up a cup, I can pick up a sewing needle teeny tiny, I can pick up this little poof ball, and replicating that for a robot gets tricky because robots have specific jobs. So if we want a robot to pick up something big, it's fingers have to behave differently than if we want them to pick up something small. So we're going to build a robot hand. So first things first, we have to understand how our fingers work. So when I decide to use the muscle in my hand that pulls tendons and muscles, and when I want to move my finger down, I just literally make it move down. So we have to build a replicable finger. We have to build something that acts like a finger. So we're going to use this straw. Now I have thick straws, you can use a thin straw, it doesn't matter. But what I'm going to do is I'm going to carefully show you how we build a joint. And we're going to take, we're going to cut a 45 degree angle here, just like this. And now I cut out that little chip there, and when I pull it down, it bends. And when I let it go, it snaps back. And that's how you know if you've got the depth of that cut proper, because you don't want it to stay down, you want it to snap back, because we're going to use that to our advantage. I'm trying to think what I want my robot hand to be able to do. And honestly, I want it to be able to pick up these little puffers. So I'm going to make it so that I can wrap around like this and grab it and lift it up. But as you can see, one finger isn't enough. Maybe if I have a second or a third, it can grab it together and then it can pick it up and I can put it into my cup or into the bowl. So we're going to cut two more of these. So that's where my 45 is going to be right about there. Perfect. And now I have three fingers, right? So we have to take some string and we're going to put a string through here and all the way down. And then when we pull it, it's going to cause that joint to bend just like that. And I have a needle. I'm going to carefully thread this through. And now I'm going to push it through the front right here. I'm going to push down and I'm just going to push that through and it's going to kind of get stuck. So I'm going to use another needle to push it through. Okay, now it's through the strings through and I'm going to use a skinny straw and I'm just literally going to take that and I'm going to push this all the way down and then the needle comes out like that. And when I pull this out now, let's get that other straw out. When I pull this out now, I've got my string through and my needle is all the way out. So I'm going to give myself about, I don't know, 12 to 18 inches space and then I'm going to snip it here and I'm just going to tie a knot right up on the top. So I'm going to do a double knot so that it doesn't come out. And now watch this. When I pull this here, when I pull on my string, it applies force to the top part of my finger and it closes it. How cool is that? By a simple tug. So I'm telling my robot finger, pull down and it pulls down. So we're going to do this two more times and then we're going to tape it on to our arm. And now we're going to take our tube and I have this little cup and I'm going to place the cup right on the tube. Now I'm going to take a whole bunch of tape, just run it around the bottom here. We're going to attach each of our fingers and I want my finger to be pulling inward. So this is where you get to adjust the height. So when I pull on this, I want it to go almost to the center. So I think that looks good. And because I have three, I'm going to try to get those about the same height again. And I'm going to tape it on the bottom as well. How cool is that? All right. One last thing I'm going to do down here is to keep these untangled. I'm going to run my string down through this and have it come out the end here. Basically what I'm doing is I want to keep the string straight so that they're not crossing in and getting in the way. There we go. So now the test. So I have my little pom-poms and now I can literally see if I can pick them up. I need to learn how to work my hand, my robot. There we go. Oh, one, two, three, four. So give it a try. You can build a robot hand with three fingers or you can build a robot hand with two fingers or one finger. It just depends on how you want the robot to function. Remember, robots are designed to do things you need them to do. Most importantly, if three fingers does the trick and it can help you pick up things around your house, give it a try with a simple DIY.