Robot orientation: Long or wide?

Our team is designing ramps for robots to climb at the end of the match but We would like to get a sense of whether the teams are going to be using the long starting orientation (38lx 28w) or the wide staring orientation (28lx 38w) so we accomodate our designs for the wide robots if necessary.

My guess is that you will have a very very difficult time designing effective ramps to support “wide” robots, and only a very difficult time with ramps for “long” robots.

We’re not even considering a “wide” robot ramp design.

Last year, there were only a couple of robots that I could think of that went with the wide configuration. I think with this years game though, we will be seeing a lot more variety in the configuration.

This is a good poll, I was wondering the same thing.

IMHO: There are so many more cool things you can do this year with a wide robot. Designing your point scoring systems around a “long” robot may lead to overly complex mechanisms and wasted weight.

The design I made myself is a Wide Orientation robot, and I think, by far, it is better than any other design I’ve heard of yet, due to the extensive increase in capabilities compared to the vertical bot.

On that note, anyone want a pretty cool wide oriented robot design? :-p

if you consider the issue of stability, which is vital for a robot that has to reach up high, then you will find that a wide robot design might not be the best way to go. Think about how far in from the edge the wheels contact the floor, with both designs. Think about how the spacing of the contact points affects robot stability. Also think about the effect of acceleration of the robot on stability with both possible orientations.

stability.jpg


stability.jpg

This can be remedied easily (see: wheelie bar). What may be harder to fix is adding an extra joint to an arm in order to pick up from the floor or human loader because your robot isn’t wide enough to hold a tube in it.

In this game, I see a wider stance as being advantageous when fully extended vertically. If pushed from the side, the longer dimension, the robot will be stabilized. If pushed from the rear, the robot should be pushed into the rack, keeping it upright. If pushed from the front, the robot shouldn’t be in that configuration anyway and deserves to be knocked over due to poor design/poor handling. As has already been said, wheelie bars are a good thing too.

There’s the fact that a wider robot is going to have more difficulties getting up a ramp anyways due to CG issues. If you’re designing a ramp for wide bots, you should keep in mind that you’ll want to shoot for a less aggressive angle to offset this. Another thing to consider is that being able to ramp any robot out there is a pretty impressive ability to throw out in a strategy meeting.

It might be a smart thing to design a lift that can accomodate any robot design, as this poll proves that *40% of the robots which you’ll be dealing with will be “wide” configuration. Chances are, there will be a “wide” robot on the winning alliance at any given competition, and if your mechanism doesn’t accomodate them, they won’t pick you.

  • 40% at the time of posting

good idea!

thanks

What are some specifics as to why the wide platform is so much more advantageous this year?

What can uniquely be done with it that a long orientation won’t allow?

Thanks in advance,
Robinson

We made a wide robot and had some bad luck with tipping and stuff, so we decided to stay away from that for this year.

Especially since we are going to be reaching 8 ft in the air.

There is another situation which could occur. The robot could not not be the max height and/or width. It could be a square robot.

In anycase a reason to pick a wide robot as opposed to a long robot would be that it’s easy to turn. It also takes up more area around the rack so you could block easier.

Reason’s for picking a long robot are, it’s easier to build a stable long robot than a stable wide robot. You could get into the spaces between bots defending the rack easier, and it can very easily accomidate an arm.

We were discussing this today, and found that with our current design*, we could accomodate one long robot and one wide robot, or two long robots.

*still being prototyped, but it looks promising, the main issue that I can see being weight.

Last year, 340 went with a wide robot, and we needed wheelie bars to get up the ramp seen here.

IMG_6082.JPG


IMG_6082.JPG

Umm… do omni directional drive trains count as wide or as long? I think you might be seeing a few of them this year, too.

Jason

It depends which way the wheels are oriented.

A “swerve drive” system has a variable orientation, but I believe all the other drive system designs have a wheel orientation that is fixed.

A “long” robot has the wheels parallel to the long frame axis. A “wide” robot has the wheels parallel to the short frame axis. See attatched sketch.

stability.jpg


stability.jpg

Did anybody think about a square chassis? I think that if you build your robot right that a square chassis would be ideal for maneuverability.

But if I had to choose I would make it long.

Pavan.

Wheelie bar = wedge?