Chief Delphi - Hovercraft

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Quote:

Originally Posted by scirobotics (Post 791158)

it is illigal to genarate downforce with a fan

Would you mind quoting the specific rule?

It's pretty clear that anything that provides additional traction is ruled out by R06:

<R06>
ROBOTs must use ROVER WHEELS (as supplied in the 2009 Kit Of Parts and/or their equivalent as provided by the supplying vendor) to provide traction between the ROBOT and the ARENA. Any number of ROVER WHEELS may be used. The ROVER WHEELS must be used in a “normal” orientation (i.e. with the tread of the wheel in contact with the ground, with the axis of rotation parallel to the ground and penetrating the wheel hub). No other forms of traction devices (wheels, tracks, legs, or other devices intended to provide traction) are permitted.
The surface tread of the ROVER WHEELS may not be modified except through normal wear-and-tear. Specifically, the addition of cleats, studs, carved treads, alterations to the wheel profile, high-traction surface treatments, adhesive coatings, abrasive materials, and/or other attachments are prohibited. The intent of this rule is that the ROVER WHEELS be used in as close to their “out of the box” condition as possible, to provide the intended low-friction dynamic performance during the game

Note the OR OTHER DEVICES INTENDED TO PROVIDE TRACTION.

I don't think that a downward force would be "creating traction" but be closer to "increasing" traction, which I guess depending on how you look at it could "create" traction.

Quote:

Originally Posted by OScubed (Post 792767)

Note the OR OTHER DEVICES INTENDED TO PROVIDE TRACTION.

I have to agree with T3H_K3YM45T3R on this one. If you consider any device that creates a normal force to be a traction increasing device, then ballast isn't allowed (actually, anything with mass isn't allowed). This doesn't seem realistic.

haha! If u get that working post up a video! People are craving to see if it works..:D

In the late 1960's, Jim Hall designed a racing car, the Chaparral 2J, that used auxiliary fans to create suction. It greatyl increased traction, so much so that the rules were changed to make it illegal.

Here's a photo of it:

Others have made smaller versions:

This technique would certainly be possible on an FRC robot, but the question is: would it be legal?

We'll have to wait and see what FIRST says.

there is no way the compressor/motors will be able to keep the skirt inflated AND provide thrust, its just out of the question, another thing to remember is battery power...

Quote:

Originally Posted by bduddy (Post 789953)

F1 buffs will get this one.

:yikes:

EDIT: Hmm, where did the picture go? Err, anyway...
en.wikipedia.org/wiki/Brabham_BT46B

Actually, the first to use the fan concept was Jim Hall with his Chaparral 2J in 1970. Jim was a great innovator and most of the aerodynamic ideas used in racing today originate with him. His most successful from a winning standpoint was the 2E which used a moveable wing to provide downforce in corners but which could be leveled on the straights to provide minimal drag.

As usually happens, his ideas were proved so effective that they were outlawed after 1 or 2 seasons.

One of the things that happens in racing is that if you come up with a really brilliant idea, someone will try to ban it in the name of "level competition". As you write the rules tighter and tighter, there becomes less and less possibility for really great leaps of creativity...just think of NASCAR.

I worry that FIRST is going in that direction.