1. A method of determining the relative position of first and second bodies, the method comprising: providing the first body with at least first and second imaging devices at known imaging device locations relative to the first body in a coordinate system defined by the first body; providing the second body with at least three non-collinear targets; providing a known first target location relative to the first body for each of the at least three targets at a first time, wherein the known first target locations are defined in the coordinate system; utilizing the imaging devices to generate a plurality of unit vectors corresponding to a line-of-sight from the imaging devices to each of the at least three targets at a series of later times that are after the first time, wherein the imaging devices have non-overlapping fields-of-view in at least one of the later times whereby the lines-of-sight of the first imaging device are not to any targets for which the second imaging device has lines-of-sight to; generating a plurality of equations in matrix form for each of the later times, whereby, for each of the later times, a matrix of known quantities is multiplied by a vector of unknown positions that are a function of time, and subtracting a matrix including the known imaging device locations from the product of the matrix of known quantities and the vector of unknown positions, and setting the result equal to a residual error vector, wherein the matrix of known quantities includes the known first target locations and the unit vectors, and wherein the vector of unknown positions includes three unknown Euler angles, three translations of the targets on the first body relative to the second body, and distances from the imaging devices to the targets; determining a criteria defining an acceptable residual error vector; and iterating the equations to converge upon a best solution whereby the residual error vector is minimized to within the criteria.