fischertechnik community forum

For discussion:

The strong point of Bluetooth is the dynamical pairing.
This makes it possible that the BT Radio Call mechanism operates in a point to point topology what will extended the range of the Radio call mechanism. In fact every TX-C is able to act as a relay (bridge).
Decentralize approach!

The alternative is that maybe this point to point topology will be change into a star topology.
The old situation, like we had with the RoboInt RF situation.
So with one TX-C as start-manager and the limitation in distance and the lost of the advantage offer by BT.

What are your ideas about this?

Remark:
The point to point topology add also a lot of nice challenges for car robots when they are operation in clouds.
Example:
The cars are not always able to contact each other.
The developer is now challenged to develop algorithms to dynamically make use of the other members in range to keep the cloud together.

Frankly I have used enough bluetooth devices in my young life to be skeptical about dynamic pairing. I can't imagine this to work flawlessly, and if connection fails, the tools for remote diagnosing/debugging/jiggling are sparse.

Also, topology changes only start to matter at three or more devices. So it's quite an investment, and apart from schools and universities, only a few enthusiasts will ever encounter the differences. I'm all in for point to point topologies, but I doubt that the advantages will ever be fully exploited. For low-traffic, non-time critical communication, a star topology will be just fine. Anybody who tries to push the limit is probably better of with a Panda board or something Wi-Fi capable, where some great infrastructure exists.

As soon as range extending starts becoming an issue, you have already had your share of range problems. Bluetooth isn't made for ranges above 3m, period. Without any means of tweaking, resetting connections manually and having a rock-solid emergency communication line, all tinkering is cumbersome and probably not worth it.

Deutsche Zusammenfassung: Ich traue Bluetooth keinen fehlerfreien Verbindungsaufbau zu, solange man nicht die Möglichkeit hat, selbst Hand anzulegen. Meiner Erfahrung nach kann man sich nicht einfach auf Bluetooth verlassen. Wer komplexe Probleme mit so einer Minimallösung lösen will, sollte besser gleich auf eine andere, nervenschonende, billigere Funklösung zurückgreifen, für die es bessere Infrastruktur gibt.

Heiko