TRIppy The Tri Wheeler
Here is my latest little time killer, TRIppy the Tri Wheeler.
Trippy is based on a tri wheel design, with the point of this build being speed. As a matter of fact, i accomplished that almost too well. He's faster than his sensors it seems to me, although I am still playing with the code. Right now, when he takes off on the roaming code, he almost slams into things, even with the safe distance set at about 30 inches or so.
Here are a couple of pictures of him:
This is not a finished design by any means, as I plan on building on him for a little while to come. The body is actually a foam board material that I used just for getting the basic shapes i wanted. The "tape" is not really tape, but a velcro type material, I am constantly in and out of the inside, and this makes it much easier to get in and out.
The small cutout is a sharp distance sensor that gives great readings for obstacles that are within about 5 inches or so. Not very usefull on a bot that is this fast, and will probably be swapped for some longer range sensors on the next build.
The head, well, that seems to find its way into just about every project that I build.. I have a ping ultrasonic unit, a ir detector, and 6 leds already mounted, and i just seem to reuse it as often as I can. I do actually have drawings for a head that looks a little better, but i haven't had the time to work on actually cutting and putting together.
Here's a view from the top. You can't really tell it, but both of the "front" wheels have a little motion in them to allow them to sweep backwards just a little when in forward motion, that helps get a little better traction.
Here's a view of the electronics.. pretty simple, two l293d hbridges, running three motors, two sharp ir distance sensors, servo connection, ping connection. Custom Lego sensor brackets.. :)
I had actually used my own motor controller that I designed in the first attempts at this robot, but i managed to fry the hbridge in that board, and I haven't built another yet. Will order parts for that soon, and build at least two next time.
I am attaching three files here, one is the sketch to roam and ping, the other two are an xbee wireless remote code, and also the wireless receiver code to make an xbee remote controlled robot. (you can see one of the xbee shields above, but it's not used in the roaming code, and there is no xbee in the shield at that time)
Hope you enjoy my little three wheeler. Hopefully i will find access to a video recorder that works, and can post some video of this thing scooting around my house.