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View Full Version : [Project] Raja: Yet Another Line Follower



webgeek
05-31-2010, 11:48 PM
My local robotics club is sponsoring a big line-following shindig and so to keep in the spirit of things, I'm building a line following robot along with everyone else. I didn't want to buy a new microcontroller so I'm using the Axon II from my mech. I did snag some little gear motors and the Pololu line following sensor board though cause I'm lazy and didn't want to make it by hand. To keep the robot from running into other robots on the line, it's using a Sharp IR sensor to see in front of it.

Nothing too exciting overall. What makes the project interesting (I think) is that I'm trying very hard to make it more attractive and "finished/over the top :)" looking than you usually see on line followers. As such, I've attached a few pics of how it looks thus far. I try and illustrate what goes where but you have to use your imagination as I didn't remember to take a photo of the bot when it was partially assembled for test fitting.

None of these parts have been polished - the red-tint you see is from the partial tumbling some of them have recieved. Once they get fully tumbled and polished, they will be very shiny and bright. One of the more interesting and visually fun parts will be cut tomorrow.I apologize for the dirty fingernail - I took these right after finishing in the shop. Have fun!

Mike

jes1510
06-01-2010, 03:44 PM
I love the parts! They look great so far and I can't wait to see them after polishing. Did you mill them yourself?

webgeek
06-02-2010, 09:47 PM
I love the parts! They look great so far and I can't wait to see them after polishing. Did you mill them yourself?
Thanks, I appreciate it! Yes, the parts were all milled on my CNC machine. i just finished milling two more and so I only have a couple left before the hardware is done. I'll post an updated picture tomorrow. Have fun!

-Mike

webgeek
06-08-2010, 09:13 AM
Sorry for the delay, I've attached a few more images here for people to see.

-Mike

darkback2
06-08-2010, 10:21 AM
Really nice work. Seams like if you flipped the board on top around you could make some of the wires shorter, but maybe that would make others longer...I really like the way you seam to have thought of everything in your design. I always get about done with a bot before realizing I have forgotten something crucial that makes everything after it messy as heck.

DB

webgeek
06-08-2010, 10:32 AM
Thanks for the feedback! The distance from the bottom of the board to the top of the motors is TINY as is the distance from the bottom of the motors to the top of the battery. Less than 1/16" in both cases I believe. The entire height of the robot is ~2.5", width is ~5" not counting wheels. In between the two motors and the sides of the bot are a pair of speed controllers and the wiring harness, all crammed in there. No room for anything else.

Now the good news, the wires are all temporary as I'm still doing programming and adjusting. I'll be making a final wiring harness that really cleans it up soon once I've got the bot working perfectly. I'll probably make custom headers and use wire loom to run things. As it stands, one motor pulls much harder at the same settings as the other motor so the line following ability is pretty poor - it's always fighting itself. Though it's BLAZING fast for all that. The motors + wheel size are meant to give it the ability to do a bit more than 100cm/sec and that's hauling in person. It also needs the Sharp IR sensor adding into the mix so it doesn't run into bots in front of it on the line.

Sadly, the HMW plastic I'm using sucks - I HATE it. It slides on the floor well but is heavy and doesn't hold the sensor board in place so I'm going to re-work all that too. Probably going to see if I can make some aluminum skis and hit them with Teflon or such.

Thanks!

-Mike

Adam
06-10-2010, 10:53 PM
That's a beefy little robot. Very thick metal for not bearing any weight. Looks cool though.

webgeek
06-10-2010, 10:56 PM
That's a beefy little robot. Very thick metal for not bearing any weight. Looks cool though. Thanks, I didn't have anything in aluminum thinner than 0.125" and 0.25". With all the holes, it's not too heavy and honestly, it's so fast it's a little hard to debug.

Adam
06-11-2010, 07:11 AM
What kind of mill do you have? I'm really, really starting to want one!

sgarciav
06-15-2010, 09:54 AM
Thanks for asking Adam. I too am curious. I have no experience with milling at all and are very curious to see what kind of machine it is, how much of a money investment I would have to make to get something functionally similar and what suggestions there are to get started in milling. Great bot WebGeek! Thanks! SGarciaV

darkback2
06-15-2010, 11:04 AM
Not sure, but from what I can see a mill is not needed for this project. All of this could be done (carefully and with a lot of skill) using a drill press and a band/jig saw.