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Bumper switches

In this video we create and wire Bit-zee's bumper switches. Created by Karl Wendt.

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Video transcript

In this video, we're going to show you how to make a bumper switch for your bit-zee bot. So, we've got the wires connected to 1 and 3, the power's connected to 1 and 3 and you can see the LED light up there. And then when we switch the power to 1 and 2, the LED turns off when we push the switch, instead of on. So, we want to connect the wires to 1 and 3. We're just gonna double check this with our multimeter. And so, when we connect our contacts to 1 and 2, you can see that it turns off when the button is pressed. And then when connected to 1 and 3, it turns on when pressed. So we want to connect to 1 and 3. And you can see there's a 1 and 3, really small on the lever switch there. And you can buy micro-lever switches like this from Radioshack or a variety of places online. And so, now we've got our alligator clips, and we're going to bend the wire around the 1 and 3 contacts, so that we can get a good connection. And then we're going to solder those wires in place, to make sure they don't come out. And we'll use the needle-nose pliers to squeeze the wire against the connection there. And I've already put some solder on those connections to make them a little easier to solder to. There we go; we've got the first wire in place. And the number 3 connection: we're going to just clamp that down, and then we'll go ahead and heat it up, and we've got that soldered in place too. So now those wires are soldered well, and to make sure that the connection is good, and that we have everything soldered correctly, we're going to go ahead and turn on our multimeter and check the ends of the wire. So, we'll strip the ends of the wire off there, and use some alligator clips, and we'll clip to the ends of the leads on our multimeter. That way we can make sure that, yea, the switch is wired correctly, and it's working. So now we're going to take the outer housing that surrounds the bot off, and we're going to try and position the switch, so we're going to drill some holes. And we'll use the holes that are actually in the switch as a guide for our drill. It's important that you make sure that you don't drill into your fingers when you're doing this kind of close work. So you want to keep your fingers away from the drill bit itself. But we've positioned that switch so that it is right off of the edge of the bit-zee bot. So, it sticks out over the edge -- you can see right there -- sort of tangent to the circle. And that'll be important when we get the rest of our connector there in place. And we've put the screws in upside-down. That's so that when we put our speaker back in place, the bolts that are protruding won't interfere with that speaker. So, that's why they're sticking up from the underside. So we're just tightening those down again with the screwdriver and the needle-nose pliers. And we are using 12 gauge solid copper wire, and the reason is that it's pretty stiff, so it allows us to extend the lever arm for our switch considerably. So anything that gets in front of our bit-zee bot will be able to trigger its bumper switch.