So what are these estimation algorithms? There is the [[Triad algorithm]]. This is, probably, the most basic of all. It takes two vector pair inputs, perfectly aligns one vector pair (note that it relies heavily on a single sensor measurement) and then aligns the plane containing these vectors. Notice that the other vector pair may not be aligned at all!<br \>

‘QuEst’ or ‘Quaternion Estimation’ is another estimation algorithm. Yet again it aligns the plane containing the vector inputs. However, the error in the alignment of the vector pairs are a consequence of how their respective sensors are weighted. If you trust a sensor more, it is logical to minimise the error in its corresponding vector pair. One can find multiple estimation algorithms in literature.<br \><br \>