Three animals, three problems (Part 2 of 3)

A collar that avoids the satellite link by letting the animals carry each other’s data. A camera trap rebuilt as a single node with an infrared flash, no shutter sound and a 250 millisecond response. And a hill turtle under 500 grams, which ruled out GPS altogether. What each of the three systems demanded, and where one of them defeated us.

This is the second of three posts about the wildlife tracking work we did at DA-IICT between 2006 and 2013, in collaboration with the Wildlife Institute of India, Dehradun. In the first part I described how a fusion physicist came to be working on wireless sensor networks at all, how a lecture on the Zebranet project led to a visit to WII, and how one question asked in a room full of wildlife scientists produced twelve project ideas of which three were taken up. It also covered the first hand-wired prototype and the months we spent testing it on the bed of the Sabarmati river.

The three projects were deliberately chosen not to overlap: a GPS based collar for medium to large animals, aimed finally at the Barasingha (Swamp Deer); an image sensor network to photograph tigers along their trails; and a way of tracking small hill turtles inside the WII campus, where a GPS receiver could not be used at all. We called them wildCENSE, tigerCENSE and turtleCENSE. This part is about what each of them turned out to demand.

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