Where can I find a more technical description of the "logging" device that weigh less than four hundredths of an ounce?
Love to study that - power source, communication methods, etc.
Love to study that - power source, communication methods, etc.
Accuracy
In field trials at Bird Island, South Georgia, the mean
error (great-circle distance) in position estimation
of static devices was 85 km, with standard deviations
in latitudinal and longitudinal errors of 0.61° and
0.99°, respectively (BAS, unpublished data).
And some technical description in the paper, page 12 http://www.cell.com/current-biology/pdfExtended/S0960-9822(1...
I think they have a microprocessor, a battery, some sensors and flash memory. To get the data out you have to find/catch the swift and remove the device. The device wakes every 5 mins and records briefly.
According to the Wikipedia article linked by mongol, these devices can be as light as 0.3g. It's a battery, a phototube, a clock, and a recording chip. Longitude can be reconstructed from the time of most/least light, whereas the length of day and night allow reconstruction of latitude. Battery life is between 6 months and 5 years.