Onward and Downward!
The linked document outlines some of the mathematics required for analysing incoming audio signals arriving at multiple sensors (hydrophones). The challenge is to compare accurately the arrival times of the incoming signal with respect to some internal reference signal and from those results determine the differences in arrival times. In preference to this pure math […]
The linked file presents the mathematical model underlying the direction finding algorithms as implemented in the simulation program and the actual vehicle. Note that without an enormous budget, nobody in the competition can determine exactly where the pinger is. The best that can be done is to determine the approximate direction.
Hydrophone Model
The linked document outlines the method for determining the pinger frequencies to the nearest fraction of a Hertz. We don’t actually need the frequency per se, but we do need to know the signal period accurate to the nearest multiple of the DSP clock. This number is critical to locking on to the pinger burst.
Pinger […]
The linked file illustrates a possible approach to locating the Buoys with the flashing lights. Admittedly this is just a science experiment for this year, but it could give us some pointers for what to do in the future.
Buoy Challenge
The linked document descripbes the hydrophone sampling algorithms. Note that ALL the analog inputs have to be sampled on the same schedule as the hydrophones so that there is no contention for the use of the ADC. The hydrophone sampling is timing-critical so nothing should interfere with it happening exactly on schedule.
Hydrophone Sampling
The hydophones model program, version 3.0, has now completed beta testing and is released for general use. The documentation is attached to this posting. The evaluation results indicate that the large equilateral triangle is best at determining the direction to the pinger - the difference between actual and calculated bearing is less than one […]
Overview:
Timers to set our observation window to only be open for 1.3 Msec every 2 Seconds, synchronized to the ping burst of interest.
By looking at the journals of the six schools that received any points at all for locating the ping transmitter during the 2006 event, you can see that they all used some sort […]
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