Drivestation to Robot without router?

[KevinReid]

I would like to connect wireless between the Classmate DS and our Robot. Doing demos with either battery pack/extension cord for the router etc is less than ideal. Is there a way to setup wireless without using the router?

[EricVanWyk]

Originally Posted by KevinReid

I would like to connect wireless between the Classmate DS and our Robot. Doing demos with either battery pack/extension cord for the router etc is less than ideal. Is there a way to setup wireless without using the router?

We didn't have a whole lot of luck with this, but don't give up hope entirely.

IIRC, The problem is that without a router you are stuck in ad-hoc mode. AND, either the bridge or the classmate don't support ad-hoc mode (I don't remember which). BooHiss.

I think the cleanest work around is to put a router on the robot, instead of the bridge. I can vouchsafe that a WRT54GL works wonderfully with the PD and the cRIO, though it may require some configuring. I'm sure other teams have used other products as well.

I'm not a network expert, so please correct me where I'm wrong!

[Mark McLeod]

There's also the basic problem that the Classmate and bridge do not share a common protocol: a/g vs n

We put the KOP router directly on the robot and just set it up to accommodate the Classmate a/g
The router takes the same connector as the bridge, so it just drops into place.

P.S. Just passed Eric on the street in Atlanta...

[Radical Pi]

would a USB wifi-n adapter work?

[Mark McLeod]

Only halfway.
You still need a volunteer to act as the router in the relationship as was Eric's point.
or replace the bridge with a device that supports ad hoc networks.

An advantage of putting your kit router on board your robot is that even from there it can support as many other robots with regular radios and Classmates as you want

[Radical Pi]

What about not using the classmate? If the ad-hoc problem is on the classmate side, then installing the DS software on a computer that can do it might work

[EricVanWyk]

I think your best bet is to give it a shot and report back. We really need a wiki or something to keep track of these experiments.

PS - Just was rude to Mark on the street in Atlanta tonight, because I was lost and trying to find my group. Will apologize in person tomorrow.

[SteveJanesch]

Originally Posted by Mark McLeod

There's also the basic problem that the Classmate and bridge do not share a common protocol: a/g vs n

This shouldn't be a showstopper. I believe the 802.11g standard is a subset of 802.11n - same frequency band (2.4 GHz ISM), channel BW and centers, same modulation, just that .11n increases its data rate using multiple-input, multiple-output (MIMO) techniques.

It sounds like being set up as an ad-hoc network _is_ a showstopper, though.

Hey, look, my hair-splitter isn't as rusty as I thought! Hope all's going well at Champs.

- Steve

[Radical Pi]

no, I think 802.11n is on 5 GHz. Anyways, the classmate doesn't detect the robot network. I had to set up the g interface on the router to handle wireless to the classmate

[EricVanWyk]

Originally Posted by Radical Pi

no, I think 802.11n is on 5 GHz. Anyways, the classmate doesn't detect the robot network. I had to set up the g interface on the router to handle wireless to the classmate

802.11n can be in either the 2.4 or 5 ghz bands.

Also, the bridge can be configured to be in .11g. Or at least the WGA600N can be, I haven't looked at the WETxxxx.

[3286]

Well I know it can be done. We had problems getting our robot and radios to communicate after our regional. DUH..of course, we had not reset anything after the field crew set them to the required settings for the competition.

Still, we had more difficulties than we anticipated, and our veteran computer guy remarked that it seemed easier initially. In perfect 20/20 hindsight we came to this forum and found we were not the only ones who had this issue. We also noticed that teams were trying to bypass the bridge for off season non competition uses, like we are for recruiting and such.

Our solution was probably not elegant, but we simply used the reset button to allow the Router to reset to its defaults, and used the laptop software to recognize and acquire the router. I think the router had been set to the correct ip addresses for the robot per the FRC documentation, so it appears that the bridge is the problem child in our situation.

I may be wrong, this may not be much help to anyone without more detailed information, but we did find out it was possible and our robot seems to work as well as it did previously.

Mike

[jason701802]

If we replace the wi-fi card in the laptop with a 802.11n compatible one, would it be possible to connect directly to the bridge?

[Alan Anderson]

Originally Posted by jason701802

If we replace the wi-fi card in the laptop with a 802.11n compatible one, would it be possible to connect directly to the bridge?

Nope. The WGA600 bridge is not an access point, so your computer cannot connect directly to it. The bridge does not do ad-hoc networking, so it cannot connect directly to your computer.

Perhaps the easiest solution is to replace the WGA on the robot with a wireless router, as Mark McLeod suggested.

[Tom Bottiglieri]

We left our back up radio in the crate after Vegas, so we installed the kit router on our robot to practice before Atlanta.

We enabled the second (b/g) radio on the router and connected the classmate directly to that wifi network.

The big problem is you have to wait a while for the router to boot after you turn the battery on. On top of that it seemed like there would be short loss of communications. Not sure if it was slight fluctuation in supply voltage to the router, or a poor wireless radio in the Classmate... I can't speak for the PD's supply or what Intel is using inside the laptop.