pic: Ramp Video

[GaryVoshol]

Joe, it seems to me that as the middle wheel goes up, the outer wheels go down. Wouldn't this cause the bumper height to change? Bumpers must remain in the BUMPER ZONE, 10-16" off a level surface.

[Rosiebotboss]

Originally Posted by GaryVoshol

Joe, it seems to me that as the middle wheel goes up, the outer wheels go down. Wouldn't this cause the bumper height to change? Bumpers must remain in the BUMPER ZONE, 10-16" off a level surface.

Key phrase--"level surface". If the robot is set up on a level surface, are the bumbers in the bumper zone?

[betsy888]

Looks like your center wheels are 2 individual omni wheels per side, each one slaved to either the fore or aft mecanum wheel. So basically the center wheels are commanded to have the same velocity profile as the front/back wheels. Is this accurate?
btw, awesome design and thanks for sharing your ideas. We're a second year team so still need lots of help!

[Chris is me]

Originally Posted by betsy888

Looks like your center wheels are 2 individual omni wheels per side, each one slaved to either the fore or aft mecanum wheel. So basically the center wheels are commanded to have the same velocity profile as the front/back wheels. Is this accurate?

There's a ball differential so if the front and back wheels are spinning in opposite directions, the omnis don't turn.

[FlyingHedgeHog]

This may sound a tad bit pompous but that seems like lawyering to me. The way we look at it is: What's the purpose of the rule? What is it trying to stop us from doing?

Last year, there was a robot that had fans on the bottom of it at the Portland regional. The idea was to suck it down to the floor in order to gain more traction. The judges didn't let it slide and the team ended up with a box on wheels. I'm not trying to be a rules Nazi, I just think the judges won't let it pass and you'll be in some serious trouble...

[Chris is me]

Originally Posted by FlyingHedgeHog

This may sound a tad bit pompous but that seems like lawyering to me. The way we look at it is: What's the purpose of the rule? What is it trying to stop us from doing?

Last year, there was a robot that had fans on the bottom of it at the Portland regional. The idea was to suck it down to the floor in order to gain more traction. The judges didn't let it slide and the team ended up with a box on wheels. I'm not trying to be a rules Nazi, I just think the judges won't let it pass and you'll be in some serious trouble...

That specific robot design was ruled illegal by the GDC in the Q&A weeks before the competition.

The Q&A is the only way to figure out answers to designs like this.

[Brad Voracek]

You also have to watch out for your max height.

Don't make the robot 5 feet above the frame, make it 5 feet above the wheel at the lowest point.

How they would test this in the box.. I don't know.

But still, ask the Q&A if you guys go with it. Awesome drive.

[joeweber]

Originally Posted by GaryVoshol

Joe, it seems to me that as the middle wheel goes up, the outer wheels go down. Wouldn't this cause the bumper height to change? Bumpers must remain in the BUMPER ZONE, 10-16" off a level surface.

<r07>The BUMPERS must be located entirely within the BUMPER ZONE when the ROBOT is standing normally on a flat floor,

The measurement is taken when the robot is on flat floor. We meet all requirements that we have found in the rules. The bumpers are between 10 an 16 inches above the floor when on flat ground.

[Gdeaver]

If I was an inspector, I would measure your robots bumpers with all wheels in contact with the floor . Then I would ask you to full articulate the wheels and then measure the bumpers. If at both configurations the bumpers where with in the bumper zone then I would be satisfied. If not then I would turn this down. I am not an inspector nor am I a member of the GDC. You better Q & A this soon before you go farther. From the picture your bumper height appears to be variable and not fixed or static.

[JB987]

Originally Posted by Gdeaver

If I was an inspector, I would measure your robots bumpers with all wheels in contact with the floor . Then I would ask you to full articulate the wheels and then measure the bumpers. If at both configurations the bumpers where with in the bumper zone then I would be satisfied. If not then I would turn this down. I am not an inspector nor am I a member of the GDC. You better Q & A this soon before you go farther. From the picture your bumper height appears to be variable and not fixed or static.

Sure looks like bumper height would remain fixed while on the flat floor as the regs require.

[BJT]

Everyones bumpers will be out of the bumper zone when going over a bump, so if this thing is legal on the floor it seems fine to me.

[Gdeaver]

If the robot is flat on the floor and the middle wheel is articulated up, are the bumpers still in the bumper zone? This really needs a Q&A. Also with the bumpers up high this year, robot frames will be subjected to allot more stress than in past years with the low riders. Make sure those supports are robust.

[joeweber]

Originally Posted by Gdeaver

If the robot is flat on the floor and the middle wheel is articulated up, are the bumpers still in the bumper zone? This really needs a Q&A. Also with the bumpers up high this year, robot frames will be subjected to allot more stress than in past years with the low riders. Make sure those supports are robust.

If the robot is on the flat floor why would the wheels be articulated up? The articulation is not powered. the wheels follow the floor all the time.

[maltz1881]

The center Omni's are ALWAYS touching the ground, they never leave the floor. They aren't powered by anything other than the friction on the carpet when the Mec wheels are moving. The bumpers are in a permanet position. If you use the bump to manuvere around the field then no matter what your bumpers are going to change height. Meaning when you are going up your back bumper will be closer to the ground then if you were on level ground and just the opposite when going down the other side. The bumpers are solid and in the correct height while on LEVEL ground!

We have read the rules many many times and the question has been given to Q & A. We have asked many many teams in our area about it and if this is doable. Most agree with us that it is perfectly fine while others weren't sure. We are 99.9% sure that we are correct and would be shocked to see anything differently.

[joeweber]

Q & A gave us the green light, Yahooo!!!