An apparatus for determining a spatial disposition of a movable object includes a support base configured to be carried by the movable object, a first inertial sensor coupled to the support base via a first damping element configured to damp motion of the first inertial sensor, and a second inertial sensor coupled to the support base via a second damping element configured to damp motion of the second inertial sensor. The first inertial sensor and the second inertial sensor are of different sensor types. The first damping element and the second damping element have different damping properties.