[FTC]: Mecanum Wheels Axles & Hubs

[RRLedford]

Team 3507 Robotheosis has posted in a a prior thread on this topic:

http://www.chiefdelphi.com/forums/sh...#post1 309765

We went with the VEX wheels and they performed exceptionally well.
They have a better urethane formula than the Andy Mark wheels for traction purposes, and they were extremely durable and strong, despite their plastic hub.

We had the most mechanically sound mecanum drive in the state (Illinois), and in two matches during autonomous, we even became pinned under the balance beam while continuing to drive forward. we lifted the entire bridge, going up on only our rear wheels and started sliding it across the floor. No damage to wheels, axles or any part of robot.

We refuse to use Tetrix axles as their inferior strength is an insult to good engineering design. After drilling and reaming out the square hole VEX wheels to 3/16" +.001, the grade 8 10-32 cap screws were used to capture the wheels between a nylock nut outside and the Tetrix hub adjacent to our sprockets inside. The four holes of the Tetrix hub were used as drill guides to drill holes into the VEX wheel plastic ( partially thru), so that over long 6-32 screws would then penetrate into & engage the plastic hub and help transfer torque. Shoe Goo urethane adhesive also bonded the sprocket/hub assembly to the wheel hub. Wheel runout was kept very minimal by selecting the straightest screws (all were pretty good), and the unthreaded bearing zone was polished (not much needed).

We won our first regional as captains of the winning alliance, and at state we were 2nd place after qualifying rounds. Because we also do FRC and we are a small team, we did no work on the FTC robot for the 2 months between regionals and state. I have no doubt we would have won state had we spent time tuning performance and practicing during this period.

We were most consistent flag winder, largely from our better lateral positioning with the mecanum drive, and we were able to double hang after a completing a flag wind. Next year we plan to implement a four-wheel independent suspension to further improve the mecanum drive train.










-Dick Ledford

[5383robotsrule]

hi does anyone have the teleop code they used to drive their mechanum drive for robotc or labview i would appreciate it.

[orangemoore]

Originally Posted by 5383robotsrule

hi does anyone have the teleop code they used to drive their mechanum drive for robotc i would appreciate it.

We don't or at least not yet. Last year we used labview this year were using RobotC

Sorry.

[5383robotsrule]

i understand i used labview last year but quickly realized that robotc has more power.

[Ether]

Originally Posted by astroman31

mechanum

Originally Posted by MattRain

mechanum

Originally Posted by 5383robotsrule

mechanum

http://youtu.be/LlSoEfAW47I?t=3m33s