C-Base Warning

[Brandon Holley]

By "sides" do you mean front/back or left/right?

I believe the C-base is designed for a 6WD with a dropped center configuration. This is an INTENTIONAL feature of the drive base because it will allow your robot to gain the traction of a 4WD, without the turning difficulties that arise from that. If you search CD for "6WD Dropped Center" or "West Coast Drive" you will find many examples and discussions about this type of drive train.

Feel free to ask any questions you may have here as I'm sure myself or many others would be happy to add some clarification for you.

-Brando

Edit: Beat twice in the time it took to type up my response!

[P. Fuller]

This year, our drive system is going be 4 traction wheels in the back of the robot, and 2 omni wheels in the front. They are all going to be powered by one motor on each side (by linking chain.) Will the dropped center wheels be a problem?

[Brandon Holley]

Originally Posted by P. Fuller

This year, our drive system is going be 4 traction wheels in the back of the robot, and 2 omni wheels in the front. They are all going to be powered by one motor on each side (by linking chain.) Will the dropped center wheels be a problem?

No, but the omni wheels are really not necessary for your setup. You could use 6 traction wheels and achieve the same effect you are trying to get with the use of omnis.

-Brando

[JesseK]

This is a great lesson for you guys! It's a real eye-opener to the intricate details in the design of things. Hopefully it won't take too much to fix. While you put it back together, pay attention to the details of how you put the drive train together -- the wheel, their spacing, everything should be a perfect mirror of the other side.

Doing so increases quick maintainability, efficiency, and resolves drive train skew when attempting to drive a straight line.

[Mark McLeod]

Originally Posted by P. Fuller

This year, our drive system is going be 4 traction wheels in the back of the robot, and 2 omni wheels in the front. They are all going to be powered by one motor on each side (by linking chain.) Will the dropped center wheels be a problem?

I just wanted to add a note.

Even if you are not using the 6wd center wheels and are going with a four wheel drive setup you MUST make sure that all four side frames are setup with the center hole down, because the other axle holes are also offset from the centerline.

[Spirator]

We had a great evening of learning. We reconstructed the entire robot in under an hour!

[Mr_I]

Originally Posted by Spirator

We had a great evening of learning. We reconstructed the entire robot in under an hour!

NOW you know you're in FIRST! Congratulations on the quick rebuild.

[sanddrag]

I'm not sure if they have Home Depot there in Sydney, but think of it this way: Would a Home Depot lumber cart turn if it didn't rock?

[Spirator]

I understand the analogy and the physics behind the design. This thread was just implemented in order to give other teams a heads up in case they were wondering why their drive base was misbehaving.

As for the quick rebuild, it was really exciting to have a time of such critical thinking and delegation. We have a lot of new members on the team this year and this was probably their FIRST troubleshooting experience.

Overall, it was a great night for the whole team, one to remember.