[video] ThunderChickens 217 Auton REVEALED

[Qbranch]

Originally Posted by Jetweb

That is amazing but i would hate to see it if someone was in your way

Yeah... I second that... our robot already got run in to by an autonomous mode and we were just waiting for a practice round to start!

I'm glad we aren't the only ones doing high speed fully autonomous laps.

*makes note to finish up adaptive cruise feature*

-q

[Brandon Holley]

verrrry impressive.... what speed is the bot running at ?

[Grant Cox]

Originally Posted by Uberbots

i like the encoder approach though... i assume your coprocessor is doing some fairly complex vector operations to get an angle out of the encoders?

I'm not on the programming team (I just wrote here what they told me to put), but I understand it is doing some serious error processing calculations to keep it straight (beyond that I couldn't tell ya).

To all asking about the speed, I'm not sure off the top of my head. I know it was calculated at 17fps (in design), I'll see if we can get a more accurate measurement today.

Originally Posted by CraigHickman

I notice your ball seems a little... flat?

If you look closely, you can see chunks of 06 poof ball being used as pseudobumpers on the corners

[tdlrali]

She made weight?

[Grant Cox]

Originally Posted by tdlrali

She made weight?

120.0 out the door, driving and fully functional =)

[tdlrali]

120.0 out the door, driving and fully functional =)

Engineered that way, or cheesehole'd that way?

[Mike Harrison]

We prefer to call it Jenny Craiged...

[SSMike]

Originally Posted by Alex Cormier

sounds like it's another great bot.

That it is.

You looked like you might have been able to do this so I'll ask: Have you guys considered not finishing the lap and trying to dislodge a ball from the overpass? It seems like you have a mechanism for doing so.

Other than that I have nothing more to say except that that was an amazing video.

[Paul Copioli]

Here is a link to one of three pictures that may answer some questions:

http://www.chiefdelphi.com/forums/sh...ad.php?t=64709

[Mike Copioli]

Originally Posted by Uberbots

i assume your coprocessor is doing some fairly complex vector operations to get an angle out of the encoders?

We use the co-processor as an interrupt driven encoder tick counter. It also performs all of the floating point math for calculating arc-length and theta. Arc length is simply the sum of the ticks of each encoder divided by 2. We then calculate the difference in arclenghth of each encoder. Since we know the distance between the two encoders (robot diameter) we can calculate theta. Using an external processor guarantees that no encoder ticks will be missed due to program flow latency or high priority interrupts like the ones used on the RC. We are using 128 bit quadrature encoders that are measured on both the rising and falling edge of each pulse. This gives an effective resolution of 256 ppr.