Beware of R16 your robot design may be too big.

[scottydoh]

Originally Posted by Stud Man Dan

I wouldn't take that mantra to heart when designing your bot there are enough irate Engineers/Designers/Caders out there that will make sure it gets enforced and I'm one of them lol. I'm pretty sure this rule and this rule alone is what woody meant by simplicity on the other side of complexity.

but how do you plan on enforcing it?, are you going to run out on to the field with tape measures everytime your get suspicious about a bot?

[esisso]

bumpers only need to cover 2/3 of the robot, one can simply not put them in the front. i highly doubt u'll be hit from the front since all robots are moving counterclockwise. therefore, you have 38 inches of the robot plus 42 for an arm

[GaryVoshol]

Originally Posted by esisso

bumpers only need to cover 2/3 of the robot, one can simply not put them in the front. i highly doubt u'll be hit from the front since all robots are moving counterclockwise. therefore, you have 38 inches of the robot plus 42 for an arm

You forgot width in your calculations. The maximum dimension will likely be across the diagonal of your robot - including the side bumpers.

[esisso]

Originally Posted by GaryVoshol

You forgot width in your calculations. The maximum dimension will likely be across the diagonal of your robot - including the side bumpers.

wait so this rule is fully extended diagonally wise and not length wise?? im not sure i understand

[jgannon]

Originally Posted by scottydoh

but how do you plan on enforcing it?, are you going to run out on to the field with tape measures everytime your get suspicious about a bot?

That's how we enforced the 72" rule last year... I expect that we'll do the same again.

[Schnabel]

Here is something to look at and think about. Even though 80" can get very small very fast, that is a lot of space. Also, the further you go out, the hight center of gravity you will have, thus the ability to be pushed over easier.

[Ian Curtis]

Originally Posted by Schnabel

Here is something to look at and think about. Even though 80" can get very small very fast, that is a lot of space. Also, the further you go out, the hight center of gravity you will have, thus the ability to be pushed over easier.

What I'm gathering from Paul's post is that it is not the grabbing the ball that's the hard part. It's designing the arm to move the grabbed ball up in the air without extending out of your personal cylinder.

In case that doesn't make sense, stand in front of wall and extend your so that it's parallel to the floor, and move up to the wall. Then, move your arm so at a 45 degree angle down, and then to 45 degrees up. While those 45 degree positions may very well be in the cylinder, when the arm is parallel to the floor, it is not. That's where the design gets tricky, and the arm gets complicated to stay within that cylinder.

[Gary Dillard]

Time to think outside the box, but inside the cylinder.

Why does it have to be an arm? Why does it have to be a rotational joint? You can translate infinitely high. Why do you need something besides your robot's forward velocity to impart lateral motion to the ball? Forward initial velocity plus vertical force equals a trajectory.

[David Guzman]

We had to redesign 80% of our robot because we were about 3 inches out of the cylinder. We hope this rule will be STRICTLY enforced. We also hope that they DO NOT change this rule.

[meaubry]

Yes, this rule does require alot of forethought.

Remember that when slicing horizontal sections, the size of the sphere gets smaller and smaller the farther you get from a centerline section, even though the center point stays in the same location.

Claw radial geometry works best if you keep the pivots as wide as possible.

And after grabbing the ball , you may want to consider doing something with it to get it closer to the robot.

Good Luck all - this one will hurt your brain, but it's all in a good way.

Mike

[OZ_341]

Originally Posted by David Guzman

We had to redesign 80% of our robot because we were about 3 inches out of the cylinder. We hope this rule will be STRICTLY enforced. We also hope that they DO NOT change this rule.

Yes in 2002 we decided against a mini-bot to stay within the entanglement rules. When we arrived at competition, every team with a mini-bot ruled the field.
If they let teams slide by on this cylinder issue, it would be extremely unfair to the teams that are currently racking their brains.

If FIRST is going to change the rule they should do now or make a statement that this rule will be strictly enforced. I know you can't make this statement for every rule in the manual, but this one is a make or break decision for teams.

[Sunshine]

Our team ended up recalculating the size of our chassis after reading this thread . We put the "just to be save" factor into our design. In other words, we discussed "worst case" scenario interpretation of this rule.

We ended up reducing the length of our chassis.

Thanks CD and the CD community. I believe that you saved us major headaches down the road.

[Gary Dillard]

Originally Posted by OZ_341

Yes in 2002 we decided against a mini-bot to stay within the entanglement rules. When we arrived at competition, every team with a mini-bot ruled the field.
If they let teams slide by on this cylinder issue, it would be extremely unfair to the teams that are currently racking their brains.

Don't EVEN get me started on that one. (Reference any of the dozen threads I have mentioned the mouse bot)

[mathking]

I am going to chalk this one up to a good engineering experience for the kids. We did not pay close enough attention to this, and it turns out one of our two possible lifter designs is an arm which will be about 2.5-3.5 inches too long when it lifts through horizontal. Since the arm design is completely done already, we will have a great ball remover (minus the grabber) if we can't get the other system to work!

On a side note, I do not think it will be that hard to referee this one. If you are designed to lift a ball, they will ask you to demonstrate it at inspection and they can measure then.

While it is giving me some increased blood pressure this weekend, I think this rule will make for some great fun as well.

[StevenB]

On a side note, I do not think it will be that hard to referee this one. If you are designed to lift a ball, they will ask you to demonstrate it at inspection and they can measure then.

Until you do it on the field though, there isn't any penalty. They can't fail your inspection because of it, any more than they would be able to fail you for being able to violently ram another robot. The most they could do is make a list of robots to watch.
It's possible that FIRST would make a rule saying that your robot has to be mechanically incapable of exceeding the size limit, but I find that unlikely.
I can see them pulling out tape measures, but as I mentioned above, that isn't equivalent to making sure to robot fits in a cylinder.