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Our project is about dropping a payload from a UAV on the specified area. We are using an accelerometer (connected to the Arduino board) to measure the velocity of the plane (assuming the initial velocity to be zero). Is it possible to accurately measure the velocity of a plane moving in the air for a time t? Will this method be feasible?

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    Is there a reason why you can't use a GPS system? Dec 12 '16 at 17:27
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Not with any measure of accuracy, no.

You're basically asking about Dead Reckoning which is problematical at best - and when doing it with just a low-grade accelerometer it can't be anything more than a rough "It's moving quick" or "it's moving slower now" accuracy.

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  • I'm a little interrested in this, what happens if we remove the high accuracy contraint, is it possible, with something like an MPU6050, mesure a the velocity to, maybe an accuracy of +- 10km/h?
    – Dat Ha
    Dec 11 '16 at 16:06
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    @DatHa: No; this won't work reliably without a source you can use to fix your position or velocity. An accelerometer can only measure acceleration. Measuring velocity requires continuously integrating the accelerometer over time, but because you can only sample finitely many times per second, you will gradually accrue errors in your estimation until it becomes completely useless. Dec 11 '16 at 17:37
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    It's even worse than that: to get position requires double-integrating the velocity over time. It works on paper, but in the real world, physical disturbances and electrical noise soon dominate the sums, rendering them useless very quickly.
    – JRobert
    Dec 11 '16 at 22:05
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No, it's mathematically impossible. Accelerometer returns acceleration, not velocity. You can calculate, but not measure, the velocity, as an integral of acceleration, but integral is a sum of delta values plus a constant. You can measure the delta values (the acceleration), but not the constant value, so you don't have enough data to calculate the velocity.

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