Is it possible to determine if vehicle rolled back on slope or hill using gps or acclerometer?

Question

I have a vehicle with a tracker installed. The device has a gps syst, 3-axis accelerometer, 3-axis magnetomet and a gyromeyet. Is it possible to determine by how much the vehicle rolled back on a slope or hill. Using gps angle wasn't an option as the angle given for short backward movement isn't always reliable. Can accelerometer be used in such a scenario??

Answer 1

You're right that the GPS angle (heading) will not help you in a single-antennae setup. On its own a GPS receiver needs a minimum distance of movement to determine heading.

A simple GPS receiver, when used without GPS corrections (which is the case for off-the-shelf GPS devices and mobile phones/tablets), has a minimum ~5 meter accuracy. That's why a short backward movement will not yield the desired results.

In construction/mining applications, there is often a fixed GPS base station nearby that broadcasts GPS corrections, which allows vehicle-mounted GPS receiver to apply corrections, reduce error and ultimately get centimeter-level accuracy.

So in conclusion, your 3-axis accelerometer will likely be the only sensor that you can rely on until your vehicle has rolled back at least 5 meters.

If your accelerometer is sensitive enough, you'll get measurable sensor values. However, if you rollback is very slow, where the G forces are almost imperceptible to the accelerometer, then you're out of luck.

This is assuming that you want near real-time detection of vehicle rollback.