What Flarm calls "prediction" I think that most likely is a simple
projection. It is quite likely calculated worst than how we calculate the
best point to turn in thermal.
I am referring to the "Beep" in Zanders, or in some flight computers .
If you want to see how a "prediction" is working, look at the thermal
Orbiter I have programmed
https://github.com/LK8000/LK8000/blo...lc/Orbiter.cpp
which is quite similar to what Zander and SeeYou Mobile (and possibly other
software, I don't really know) do.
This is a prediction based on turning angle, estimated banking etc. and I
mention it here for a reason:
there is floating point math involved in such kind of predictions.
We use 400mhz or best ARM cpu on PNA-PDAs.
Flarm is tuned to "predict" on a 8mhz CPU by Atmel, a reduced instruction
set microcontroller that has no math coprocessor and cannot do floating
point calculations natively.

A prediction seems like something magic, and I doubt this is the case.
Each device (flarm, dsx) transmits its own position "predicted" with a
simple projection for the next second .
If your own device matches its own "predicted" position with the one
received from another one, it beeps.
That's how it works.
A projection cannot predict when you level and go straight, nevertheless as
you say it works .
It can not work "very well", as you say. But it is better than nothing.

The assumption is that the glider in thermal with you, or arriving in front
of you, has a device with the same protocol.
In the alps this is no more granted. This is what this thread is about.

greets
paolo




"Tango Eight" wrote in message
...

On Tuesday, May 26, 2015 at 7:44:07 PM UTC-4, Lucas wrote:

Tango Eight, your statement is lacking of a scientific base: WHAT
demonstrates that the "prediction algorithm works very well" ?

*Extensive* end user experience.

This might be helpful: http://en.wikipedia.org/wiki/Straw_man

best regards,
Evan Ludeman / T8