Before you deploy your GPS tracking device you will set up a GPS positioning schedule so that your device will come on at the appointed times and attempt a GPS position. But if you study an animal that spends a lot of time resting in a place where a GPS location is unlikely, a fisher inside a tree hollow or a rabbit underground for example, the GPS may turn on when the animal is in one of these resting places. If that happens your GPS device will be wasting battery when it turns on to take a location without being able to acquire GPS signals. For you this is totally wasted battery life, you get nothing for it. But we have a way that you can program that GPS position but the GPS won’t attempt that position if the animal is found in the condition described above. We call this Smart GPS and this is how it works.
The basic function can be described as a 3-axis accelerometer informing the microprocessor about movement levels and using that information to determine whether or not to attempt the next scheduled GPS attempt or to save the battery usage and just skip it.
There are 4 parts to Smart GPS.
- A minimum activity level that must be exceeded in order for the next GPS to take place. In this way you are in control over what constitutes a resting animal.
- A counter which keeps track of instances of this minimum activity level being exceeded. In conjunction with the minimum activity level above this gives you more control over what constitutes a resting animal.
- A function that enables you to choose when the “instances of exceeded activity level” counter resets back to 0. This helps you to protect your data set from just being totally empty in the case that you set either the minimum activity level too high or the counter too high.
- A function that temporarily disables Smart GPS based upon movement information. This function protects you in the case that you set the activity level and counter too high.
To elaborate, before deployment you will set all of these parameters. Setting the minimum activity level is done simply by inputting an arbitrary number into the software. This number represents an activity level that must be exceeded so that Smart GPS won’t take effect. The user software enables you to see what this number represents in terms of movement because you move the collar while looking at the user software and you can see that number change as movement intensity changes (GPS device connected to PC by USB cable at the time you do this).
The counter needs to know the minimum number of instances (x) that the movement intensity described above must be exceeded in order to disable the Smart GPS the next time the GPS should turn on. In other words, since the counter started counting the minimum activity intensity must be exceeded X number of times or else the next scheduled GPS position attempt will be skipped.
Another setting allows you to control the way in which the counter resets itself. The counter will always reset after a scheduled GPS location takes place. Other than that your counter works in one of two ways. The first is that it will always reset to 0 at the time of a GPS location that was skipped because the minimum activity level was not exceeded enough times to warrant a GPS location. But what if you set that counter number much higher than you should have? You will be missing out on a lot of GPS data. To protect yourself from this you can choose to have the counter to continue accumulating instances of the minimum intensity occurrences even if the time for the next scheduled GPS instance has arrived and been skipped.
Finally, yet another way to protect your data set from the mistake of setting either the minimum activity intensity too high or setting the counter too high. This last feature allows you to force the GPS to totally ignore the Smart GPS feature after X number of consecutive skipped GPS attempts. In other words, the animal has not moved enough to over ride Smart GPS skip. This can be because the animal really is not moving much or it could be because your settings are too high. Choose a number from 1 to 99 and use that to program this feature and then the GPS will always turn on after that number of skipped GPS positions regardless of movement.