Supershifters and Mechanum wheels

[Anupam Goli]

Could you possible provide some pictures of the drivetrain? Ideally, there should be a lot of resistance in the direction perpendicular to the forward-backward motion. The key to being able to turn a long robot is to have that drop in the center wheels. This way, the robot is on the front 2 and mid 2 or the back 2 and mid 2 wheels, never on all 6. This reduces the length of the drivebase effectively in half, requiring less torque for the robot to turn in place.

Also, make sure you look at all of the other issues before putting in a new transmission in the drivetrain.

[bs7280]

Originally Posted by Wing

Could you possible provide some pictures of the drivetrain? Ideally, there should be a lot of resistance in the direction perpendicular to the forward-backward motion. The key to being able to turn a long robot is to have that drop in the center wheels. This way, the robot is on the front 2 and mid 2 or the back 2 and mid 2 wheels, never on all 6. This reduces the length of the drivebase effectively in half, requiring less torque for the robot to turn in place.

Also, make sure you look at all of the other issues before putting in a new transmission in the drivetrain.

Thank you for the advice! I am pretty sure that you are right, in that our center wheel is not lowered. we are meeting tonight and I will be sure to check it out and grab some pictures.

Also keep in mind that we are only going to make minor changes to our competition bot if any (no major drive train changes) like flipping the frame. In the off-season we intended to experiment with frames (among other things) that are not intended to compete. We have good programmers, tools (mills,cnc,lathe) etc... that if we were optimistic we might attempt to build one of the complex drive trains as a prototype.

[FrankJ]

Ether: A big reason that I am an engineer is that mom knew I would fail miserably as an English major & starve.

For all of you that plan to major in engineering for the same reason.... Being able to communicate is really really important.

[jbsmithtx]

I think several people her have fallacies with mecanum. Our team decided week one to use them this year, and we did spend a little too much time perfecting it, but in the end it turned out for the better. We were a feeder station/shooter and we found the mecanum great for lining up. This was the problem we had last year. Even with all the summer practice I got with last years bot (hours upon hours) it still was not all that great. So our team debated week one and saw the omindirectional system as very advantageous, versus the challenge last year. Our original intent was to dive under the pyramids and such, but we never got to end up doing that because of the slight variations in pyramids. However, during competition when our shooter failed, we were plenty good at defense. (Youtube video. Not sure how much defense is shown.. http://www.youtube.com/watch?v=3M_YGV9kKP8). We actually pushed several teams with the kitbot around. We did find it easier to drive aroudn them though. We discovered (all too late), that speed would have definitely helped. I think a lot of teams underestimate speed. When are robot can drive around you, or simply quickly out maneuver you with a mecanum, it really makes a lot of things easier. Our teams has nothing bad to say about our mecanum, just make sure that you use a gyro to help with all the subtle problems. We used 6" AM mecs with TB minis

Also forgot to include that when we decided to add a climber, rather than messing with other systems, we were able to mount our climbers on the side and strafe onto the bar