Chief Delphi - GPS at FRC Regionals?

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Re: GPS at FRC Regionals?

Quote:

Originally Posted by EricH (Post 1296451)

It's not for tracking strategy at all!

Good point Mr. Husmann; I retract my comment :)

Re: GPS at FRC Regionals?

Quote:

Originally Posted by wireties (Post 1296247)

GPS is a line-of-sight technology. It pretty much does not work indoors.
Commercial GPS receivers do not give us the resolution necessary for FRC.
Differential GPS (like that provided by the Coast Guard for coastal navigation) is much better (maybe a few feet) but stiii not good enough for FRC. But some other radio-based navigation element would be cool in autonomous mode, perhaps a simple directional beacon of some sort?

Quote:

GPS has been tested by several teams in several venues with disappointing results. Many modern venues have too much steel in the roof deck to get a good GPS lock.

As I described, adding multiple repeaters on the roof of the venue and re-transmitting the GPS signals indoors would resolve the indoor tracking issues. Differential GPS can provide inches, not feet of precision -- which is plenty of resolution for the FRC field.

Here's a quick article/caption that mentions the concept:
http://www.engadget.com/2007/02/21/u...your-position/

Apart from this, creating a local positioning system environment as described in this thread may be feasible using an RF based system (rather than attempting to detect field objects visually, which in my experience has been quite error prone due to unknown and varying field lighting conditions)

Re: GPS at FRC Regionals?

Quote:

Originally Posted by seg9585 (Post 1296999)

Here's a quick article/caption that mentions the concept:
http://www.engadget.com/2007/02/21/u...your-position/

It's not nearly that easy. See this article for a description of the problem and one possible solution: http://www.insidegnss.com/node/1581

Re: GPS at FRC Regionals?

As for the accuracy of GPS you can get around 5 mm accuracy in a dynamic environment with a GPS base station. However these systems are very expensive.

Another major problem is the software needed to correctly interpret GPS information. To do this you need a Kalman filter and a good IMU. This is a very fun project but is well beyond high school level programming.

This all being said i would love to see FIRST implement a GPS system