5 ms·
One wolf's migration across Europe
- mschuster91 12y agoI would like to know how they kept the battery alive for over a year with all that power-hungry stuff in there...
- reubenmorais 12y agoThe collar sends its location every 3 hours = 7 times per day = 2555 times over a year, for a couple of seconds each time. If on average each wake up lasts 5 seconds, that's only 3.5 hours over the year, so definitely within the range of commercial batteries.
- cloudwalking 12y ago5 seconds is fast to acquire a GPS fix...
- Malstrond 12y agoA SiRFstar with satellite prediction (SiRFInstantFixII) might be able to manage it.
- z92 12y ago5 seconds is too fast to acquire even a GSM fix to send the data.
- miahi 12y agoWith a cold start - yes. But most GPS chips have memory backup for short-term almanac data (valid for up to 4 hours, works if the GPS doesn't move long distances in that time period) and internal clocks, so it can perform a warm start. This takes only a few micro Amps standby current, so it's not hard on the battery.
- mschuster91 12y agoEven with A-GPS, a GPS fix takes longer to obtain, and data transfer with GPRS takes ages... add the space constraint of a collar, and it becomes really complex.
- mig39 12y agoDoes SMS use GPRS? The article says it sent its position by SMS.
- ripperdoc 12y agoSMS doesn't use GPRS, it's sent on a special channel
- masklinn 12y agoSMS uses the control channel of GSM.
- mschuster91 12y agoAGPS requires GPRS data.
- michaelt 12y agoOK, so assume the GPS receiver takes 60 milliwatts [1] for 60 seconds, four times a day. You'd be using 0.66 milliwatt-hours per day. (Other receivers claim to use as little as 8 milliwatts [2]) A D cell alkaline battery, depending on the manufacturer, can have 20,000 milliwatt-hours or more [3]. Two of those and you could have 4 years of battery life. Assuming your batteries retain their advertised capacity when dragged around in snow and ice by a wolf for a few years! [1] https://en.wikipedia.org/wiki/SiRFstarIII https://en.wikipedia.org/wiki/SiRFstarIII [2] http://www.csr.com/products/25/sirfstariv-gsd4t http://www.csr.com/products/25/sirfstariv-gsd4t [3] https://en.wikipedia.org/wiki/D_battery https://en.wikipedia.org/wiki/D_battery
- chiph 12y agoTemperature certainly has an effect on batteries¹. But also that the periods of high current demand were spaced so far apart -- the batteries had time to recover. Much like how the battery in your car is a "starting" battery -- high current is needed only occasionally to start the engine, with the alternator making up the demand the rest of the time. ¹ Dad used to work for Union Carbide, which owned the "Eveready" brand at the time. One of the projects he worked on was a battery for the Union Pacific Railroad. It was designed to be buried in the ground in remote locations to run signal systems. Burying it gave it a more constant temperature. If the researchers placed the battery on the inside of the collar next to the wolf's fur, that could really extend it's life.
- thaumasiotes 12y agoEvery three hours is 8 times / day, so 4.0 hours / year.
- aptwebapps 12y agoI doubt this is the case, but you could have sort of charger to keep the battery topped up that was based on the automatic winding mechanisms of some watches.
- deleted 12y ago[deleted]
- maxerickson 12y agoHere's a listing talking about Slavc: http://www.volkovi.si/en/about-wolves/wolfs-ids http://www.volkovi.si/en/about-wolves/wolfs-ids Which gets us to here: http://www.vectronic-aerospace.com/wildlife.php?p=GPS_Plus_Collar http://www.vectronic-aerospace.com/wildlife.php?p=GPS_Plus_C... http://www.vectronic-aerospace.com/wildlife.php?p=battery_size http://www.vectronic-aerospace.com/wildlife.php?p=battery_si... They spec the batteries in terms of how many positions, with a 1C battery in the GSM collar giving at least ~1100 positions. They are apparently obsessed with efficiency. It's also cool to see that the collars have a remote (or timer) triggered drop off system.
- PhantomGremlin 12y agoWe've seen similar migratory behavior from wolves in the USA. Here's an Oregon wolf that has gone over 1000 miles: http://en.wikipedia.org/wiki/OR-7 http://en.wikipedia.org/wiki/OR-7
- mprovost 12y agoIt's a different species, cougars, but this is an interesting story of one that was killed by a car in Connecticut, and which was identified as having come from South Dakota, 1,800 miles away. http://griffinsguide.com/content/2014/01/06/cougar-makes-an-incredible-journey/ http://griffinsguide.com/content/2014/01/06/cougar-makes-an-...
- miahi 12y agoThis reminds me of an anecdote from a local (European) telco: A customer called the customer support line because their monthly invoice was way higher than in the previous months. They had 3G data access modems/SIMs and a fairly standard contract. The CSR searched their record and found that they had a lot of roaming data fees (really expensive if you don't have a special contract). The customer then replied "I see. Well, we use these data SIMs in special collars to monitor some bears... One of them went abroad."
- aptwebapps 12y agoThere's an advertisement in here waiting to happen.
- Kiro 12y agoIs SMS usually the way you send data from tracking devices?
- deleted 12y ago[deleted]
- maxerickson 12y agoI tracked down the manufacturer in another comment. Their devices can communicate with UHF/VHF radios, GSM and a couple of different satellite systems, Globalstar and Iridium.
- keehun 12y agoIt seems Slavc was the only one of its kind from these scientists that survived the long migration.
- stplsd 12y agoWolfs community is very concerned about this. There is initiative from senior members to held conference about fighting for wolfs right to privacy.