A worn head-up system for displaying information pertaining to the piloting of an aircraft, said information being conformal to the real outside world and delivered via an SVS synthetic vision system, comprising:
- a worn head-up display D0, and
- a DDP subsystem for detecting cephalic posture, comprising a tracking mobile first element D1 that is tightly attached to the display D0, a fixed second element D2 that is tightly linked to the platform of the aircraft, and a means for measuring and determining the relative orientation M12 of the tracking mobile first element D1 with respect to a reference coordinate system of the fixed second element D2 linked to the platform, and
- an inertial device D3 for delivering the relative attitude M3t of the platform with respect to a terrestrial frame,
- a device Dp for delivering the position of the aircraft with respect to the Earth, and
- an SVS synthetic vision system for delivering a synthetic terrain image on the display D0, said image being dependent on and automatically controlled according to:
- the position and relative attitude M3t of the aircraft, which are measured by the positioning device of the aircraft and the inertial attitude device D3, respectively, and
- the relative orientation M12 of the tracking mobile first element D1 with respect to the fixed second element D2 of the DDP posture-detecting subsystem;
- and
- a dual harmonization subsystem for aligning the display D0, the DDP posture-detecting subsystem and the inertial attitude device D3 with one another,
- the worn head-up system for displaying piloting information that is conformal to the real outside terrestrial world being wherein:
- the harmonization subsystem includes a dual harmonization processor and an HSI human-system interface incorporating a function for readjustment of the conformal head-up display;
- and
- the dual harmonization subsystem is configured to:
- launch the readjusting method by activating a readjusting mode at a readjusting-state start time t1c, all or some of the conformal piloting information being displayed, in a readjusting state, frozen on the display with respect to the movement of the tracking mobile element D1 and free with respect to the movement of the aircraft, and memorizing together the readjusting-state start time t1c and the corresponding relative orientation between the tracking mobile first element D1 and the fixed second element D2 of the DDP posture-detecting subsystem;
- then
- carry out a series of a preset number N of measurements of relative orientations {circumflex over (K)}l, varying from 1 to N, of the tracking first element D1 with respect to the fixed second element D2 of the DDP posture-detecting subsystem, i.e. the element linked to the platform, these measurements corresponding to targeting actions Vi, i varying from 1 to N, during which the various elements of piloting information displayed in the readjusting state are superposed with corresponding landmarks of the real outside world;
- then
- via a dual harmonization algorithm, conjointly determine the relative orientation M01 between the display D0 and the tracking mobile element D1 and the relative orientation M3t of the inertial device D3 with respect to the Earth on the basis of the rotation matrices {circumflex over (K)}l measured by the DDP subsystem, and of corresponding expected theoretical DDP rotation matrices Ûl, it being assumed that the relative orientation of the fixed second element D2 with respect to the inertial attitude device D3 is always equal to an identity matrix of rank 3.