Passive vision techniques to estimate aircraft position during landing
can be developed using a runway model, images acquired by an onboard
imaging sensor, orientation information provided by the inertial navig
ation system and the position estimate provided by devices such as the
global positioning system. In this paper expressions are derived for
the sensitivity of point features to errors in the position and orient
ation of the sensor. Using these, the sensitivity of the sensor image
to aircraft position and orientation errors along a typical landing gl
ide path are studied. A least-squares technique based on this sensitiv
ity analysis is described for the correction of position and orientati
on estimates.