http://www.youtube.com/watch?v=ZxVNmHB-r_c
1107 Family 
heres the link to their full robot
http://img9.imageshack.us/img9/3898/mike1r.png
[ImageShack - Best place for all of your image hosting and image sharing needs
a full explanation from him under this post
*with permission from 1107A
his summary:
](ImageShack - Best place for all of your image hosting and image sharing needs)
[ImageShack - Best place for all of your image hosting and image sharing needs
a full explanation from him under this post
*with permission from 1107A](ImageShack - Best place for all of your image hosting and image sharing needs)
Who’s that drinkin the A&W? They have good taste in sodas.
lol that would be me : D
Why all omnis if you don’t strafe?
How do those grippers fit in the size box?
Other than that, looks good. Clearly performed well at competition!
Omnis are great even if you don’t strafe. When the robot turns (for tank drive), there is a little sideways force on the wheel. Depending on the size of the robot, regular wheels will jitter or shake when this happens.
it fits in the box with the claws open
and as magicode said it, normal wheels just create too much friction with the foam tiles when you turn
also in regards to omni wheels, with all four as omni’s it can be REALLY easy to push a robot side ways, an easy solution is to bolt a omni wheel perpendicular to the drive wheels.
it was good(for us) that no one did a pushing bot,
and the specs for the bot 1107A;
the robot has a drive geared 3:7 with only two high torque motors. the arm has a combination of four regular motors and two high torque, which allowed us to hang with a gear ratio of 1:7(with an idler gear in between so we don’t slip the gears)
with our last two motors, we used one powering the claw with a gear ratio of 3:1 and the last motor was used to change the angle of our tower (the part where the arm pivots and where the cortex is located) this function is used for hanging,
we used our polycarbonate for building a chassis supporter (we used all aluminum and had a lot of wobble and flexing) our claw (great because it is extremely flexible and is VERY indestructible) a battery holder, and finally the gear box for our claw (we needed a box that was three inches wide and wanted it to be all one piece)
we had had some cortex and coding issues and fixed those over the day, (which is why we did poorly during the qualifiers) by the quarter finals our robot performed almost as well as i hoped.
that’s 1107A’s robot,
let me know what you think/thought, i am hoping to hear from dtengeneering as i missed our inspection and heard he liked it…
With a set of four wheels, making two of those wheels non-omni (traction) will not result skipping or jittering (perfect skid steer). No wheels need to “slip” for turns to happen, which is what causes wheel jittering. Though, this design change does put your turning center directly between the traction wheels.
With four traction wheels, that could be a problem depending on your design, as wheels do need to slip for the turn to happen.
the best configuration that i can think of would be to have 4 omnis and 2 of the traction wheels, and to align them with the center of mass. that way you cant get pushed and it does not change turning
Four omnis and two traction can still get you pushed and spun with effort on the edges. There’s theoretically no less resistance to turning than 2 traction and 2 omni wheel because there’s no turning scrub.
this is true,
however this changes your center of rotation, which with my configuration, it does not, or at least makes it the center of the robot.
all in all, i believe that it is up to the robot designer, it all depends on what they’re doing, what the driver wants, and the actual robot design.
Either that or you just round up few million dollars and get those Vex antigravity orbs they used in the animation
No need for wheels and easy hanging:D