[Eric] built this robot for the 2009 Robocup Jr. competition. The game ball has IR LEDs inside of it and this little bot uses eight IR detectors for tracking. Four motors mounted perpendicular to each other provide locomotion. Since this would normally have you traveling in circles, he used some omnidirectional wheels walled Transwheels. As you can see, they have small rollers built-in and allow movement in any direction if the motors work together. A couple of L298 controller chips handle the motors. [Eric] wrote a program to calculate the PWM necessary to drive the controllers and to coordinate movement of the wheels.
Don’t miss the demo videos after the break and, if you’re not a fan of wheels, stop by and see the bi-pedal soccer robots.[youtube=http://www.youtube.com/watch?v=OtuZ2HUR2yI]
Offense
[youtube=http://www.youtube.com/watch?v=A8fyPCxXI7c]
Defense
‘need to get perpendicular’
remind you of anything?
http://www.hitachigst.com/hdd/research/recording_head/pr/PerpendicularAnimation.html
haha :)
Mowcius
I need to get some of those wheels…
or some of these:
http://www.youtube.com/watch?v=CjcyHicm3NA
Everyone loves holonomic robots!
@Mowcius, just what I was thinking.
That AirTrax forklift was the first thing that came to mind when I saw this. What his wheels are missing is the angle of attack that the forklift has. It would be really cool is someone could manufacture some of those wheels for robotics.
Mechanum wheels would have been better.
I’ll buy that for a dollar!
Here’s both types, mechanum and omni
http://andymark.biz/holonomicwheels.html
@roboguy
that is really cool. wonder how much it costs.
@googfan
As you can see at the AndyMark.biz site, US$222 for four 6″ wheels.
Errr omnidirectional wheels have been the *standard* in RoboCup competitions for years now, even in the junior league.
I went to Graz for the World Championship last year, some of the junior teams are now even using image processing and digital compasses. Eric’s robot seems quite basic to me.
walled?
oblig XKCD:
http://xkcd.com/413/
Link to the wiki page for the wheels:
http://en.wikipedia.org/wiki/Mecanum_wheel
not cheep at all but a quick google found me:
http://andymark.biz/am-0298.html
And they look easy enough to manufacture yourself. The rollers being the hard part to source.
i’s amazing ! i whant one of these
I just volunteered to help out at a FIRST tech competition and a few of the teams had made their robots like this. I thought it was pretty cool at least.
Yeah, we have been using those wheels for years in the junior comp. Also, whats cooler is three-wheeled omni design. Which (theoretically) allows full holonomic motion. Four wheels (which we tried several times during development) doesn’t give full holonomicity, as there are directions of motion that can’t be properly achieved. … And three wheels leads to some really cool maths…
I couldn’t resist commenting. Perfectly written!