I have a RC model airplane, currently carrying a RC receiver, 900MHz radio modem, temperature sensor, pitot and static pressure sensors, batteries, GPS, and a mini video camera. I'm also planning to add an accurate altitude/hight sensor to measure airplane's height above the ground during the final landing approach.(I could not find an accurate range sensor yet).
When there are different sensors which provide the same type of data with different accuracy/uncertainities, how we can combine/fuse these data to improve the accuracy ie reduce the uncertainity of the measurement. For example, both the static pressure sensor and GPS produce altitude data. If I can add another more accurate sensor to be used on final leg of he landing approach I will have one more sensor producing the altitude/height data. So3 sensor generating same type of data (height/altitude).
I can code a simple "if then else" logic into my flight controller to switch from one sensor to another depending on the airplane's altitute. But I'm sure there must be better methods to utilize, fuse the altitude/height data from the static pressure sensor, GPS and planned new height sensor instead of having "if then else" kind of swithcing code.
Do you know how should I fuse the altitude/height data from the static pressure sesor, GPS and new height sensor so that I can obtain the best and most realistic height value for my RC model airplane?