The best thing about Zebranet is the fact that it’s actually a network solution designed for zebras! Why do zebras need a network, you ask? Well, the network is actually for scientific researchers to study the migration patterns of wild zebras as well as their daily, social behavior.
Personally, I also love two specific aspects about this work, the first being that the researchers had to design for and work with real zebras in the wild and the second, that they got to travel to Kenya to do it.
The Design Challenge
The ZebraNet proejct from Princeton University had two major parts, designing a collar that zebras could wear that would collect information about their movement patterns and designing a peer-to-peer network protocol that would allow a large fraction of the data to return back to the researchers even if many of the zebras are out of the range of the receivers.
In addition, the receivers (or base stations) are not standing devices like cellular base stations. Instead, the researchers drive vehicles around the savanna to collect the data, hoping to get in range of a few zebras.
How it works
So how does this work? Essentially, the collars collect data on the movements of the zebras using GPS. They the forward this data to other zebra collars that have historically been successful at transferring data to the base station. Perhaps these zebras are the bravest of the bunch and venture furthest from the pack, zebras with a mind of their own. This protocol allows the data from the more conservative zebras to reach the researchers despite being out of range of the base station.
Another key factor is the requirement of a very long lifetime of the collars. Zebras can’t be counted on to charge the collars every night, so the collars have to be able to store all the required data and work for several months or more without intervention. To solve this issue, the collars recharge themselves using a solar array and then use that energy very efficiently. For more details, you can check out the NSF page, or this excellent article on the BBC.
Survival in the Wild
When I first read this paper, it was right on the heels of the big San Diego blackout, and I realized how useful it would be for cellphones to function in this way when power systems are interrupted. While many users lose all form of communication, some may have backup power and internet at their workplaces, or even a cellphone connection. Emergency text messages could relay through nearby users until they found a way to an actual base station, internet connection, or even the intended recipient. The message could include GPS tracking information if needed as well.
In emergency situations, this could be very useful at getting a message out to family saying you are okay or alternatively, that you need help. With the use of newer technologies like Bluetooth Low Energy, this could be done at very low power consumption, allowing your phone to work in emergency mode for a long time.
What do you think? Shouldn’t our phones be better equipped to help us during emergencies? What other applications could be helpful in emergency situations?