Advantages to a long bot?

[jwallace15]

As a rookie, I'm not sure why some teams pick long bots to different types (all I know is Long Bot). Are there specific advantages? Does it aid strategy? Thanks in advance!

[Ernst]

Advantages and disadvantages of different robot configurations vary largely depending on what that year's game is. Long robots provide more stability when accelerating. They also allow for more wheels. They are easier to drive over a barrier or up an incline because they are less prone to tipping.

Again, though, it depends on the elements of the game.

[Grim Tuesday]

Long bots are more stable overall. Some think they are easier to drive. Stability is key in FRC-- I often see robots much taller than they need to be driving around. You can almost never go wrong with a low center of gravity. Making your robot wide requires that CoG to be lower to retain stability from tipping.

[IndySam]

We have only gone wide when the game called for it. This years game called for it in two ways; wide was smaller on the bridge and wide for a larger ball pick up area.

[Laaba 80]

Long robots are able to fit through smaller gaps. In my experience it was harder to defend a long robot than a wide one.

[F22Rapture]

Longbots are inherently more stable in the forward-backward axis. Thus, they can accelerate and decelerate quickly with less sway. Consider also that if you're crossing a barrier, like this year, a longbot would be far less likely to flip while crossing it perpendicularly. Since you're much more likely to experience instability in the forward-backward axis than the side-side axis during an FRC match, longbots are generally the better choice.

However, there are a few scenarios in which a widebot configuration might be beneficial. This year, if you didn't go for an over-the-bumper solution for ball capture, a widebot would have provided quite a bit more room for balls picked up. In pushing or highly defensive games, a widebot would provide a slight traction advantage and can turn a bit easier.

Usually though, speed is more useful than pushing power, and stability more than ease of turning, so the longbot comes out on top. A properly-done West-Coast Drive can negate several of the advantages of a widebot while also coming out ahead in speed.

[Peyton Yeung]

As a driver, my favorite bots to drive were long bots because ours didn't turn in a circle as fast. This helped refine control of the robot so when we went to a wide base for this year it wasn't that hard to control.

Peyton

[Gregor]

Originally Posted by F22Rapture

...in pushing or highly defensive games, a widebot would provide a slight traction advantage...

How so?

[FrankJ]

Not really game related, but long bots are easier to get through door ways.

[MARS_James]

In all honesty my team has only ever made long bots, after our rookie year. We like them more since it is easier to control for a driver, you can fit more wheels in a standard drive, and when we tried a wide bot with mecanums it responded weird when driven diagonally (this could have been our programming but we just didn't like it). One year where I think it was really good to use a wide bot was 2009 since it made it much easier to pick up moon rocks.

[F22Rapture]

Originally Posted by Gregor

How so?

Traction is probably the wrong word, but it's easier to deflect the force of a longbot than it is a widebot, and most longbots have drop-centers so depending on the wheel types (some teams like to put omni's in the front) and whether or not it's 6wd or only has the back 2 sets powered, a longbot on a drop-center pressed up against another robot may or may not have the same footing that a widebot which usually wouldn't have the drop-center would have.

[edit] that was a terrible run-on sentence

[Gregor]

Originally Posted by F22Rapture

Traction is probably the wrong word, but it's easier to deflect the force of a longbot than it is a widebot.

Why?

Originally Posted by F22Rapture

most longbots have drop-centers so depending on the wheel types (some teams like to put omni's in the front) and whether or not it's 6wd or only has the back 2 sets powered, a longbot on a drop-center pressed up against another robot may or may not have the same footing that a widebot which usually wouldn't have the drop-center would have.

If there are omni-wheels, then yes traction will be effected.

Drop center longbots wont be effected if they are hit from the front or back, but yes they could "spin out" if it from the side, due to the shorter wheelbase.

What does

may or may note have the same footing

mean?

[MichaelBick]

This was mentioned earlier but not explicitly stated. long bots will turn faster than a wide bot.

[IndySam]

Originally Posted by MICHAELABICK

This was mentioned earlier but not explicitly stated. long bots will turn faster than a wide bot.

Really, you sure about that?

One of the things that makes a wide bot hard to drive is the fact that it turns so quickly.

[LeelandS]

Robot orientation is generally a game decision. It usually comes down to, is being wide worth the cost of stability. In 2012, with the triple balance being such an important game piece, many teams went with a wide orientation robot to allow the triple balance to be more possible.

In most other games, there is no significant advantage to a wide robot. In fact, in most games, it could be an issue. Several games in recent years (I'm thinking 07, 08, 10 and 11) saw many long robots because the stability was an advantage; it allowed for some robot designs that required forward/backward stability. For example, in 07/11, many robots had elevators. When the elevators went up, it changed the robots center of gravity to up and to a side. On a wide robot, this is dangerous, as the robot will be more easily tilted to one side and subsequently tipped. Likewise, a robot with an arm would be in even more danger. The CoG would be elevated, and set outside the robot's perimeter, which could very easily tip the wide robot over.

In a game like 2008, a similar concept is applied. The two major game designs (a ball elevator and a catapult of some kind) would have been difficult on a wide base. Like in 2007, an elevator makes the CoG elevate and go to a side, especially when those big trackballs are elevated to 6'6" above the ground. On a catapult device, the force of the ball launching could generate a great deal of force to one side of the robot, which could tip up or tip over a wide orientation drive base.

In 2010, the bumps dividing the field were significantly larger than this year's; one foot tall, if I remember correctly. I saw some wide robots do it well (Team 86 doesn't count...), but without a doubt, robots without forward/backward stability were much more prone to tipping.

Most often, there is no need for a wide robot. In 2006, 2009 and 2012, robots with a wide drive system could have some kind intake on the wide side to aid in game piece acquisition. However, in most other years, the decrease in stability is a hindrance. Which is why most years, you see the number of long robots far outnumbers the wide.