Method for dual harmonization of a ddp posture-detecting subsystem integrated into a worn/borne head-up viewing system

A method for dual harmonization of a DDP posture-detecting subsystem integrated into a worn/borne head-up viewing system,

• the worn/borne head-up viewing system being located on-board a carrier vehicle and comprising:
• a transparent worn/borne head-up viewing device Dv,
• an exterior reference device Dref having an exterior reference coordinate system Rref, possibly either a coordinate system of the carrier vehicle or a local geographic coordinate system or a terrestrial coordinate system;
• a DDP posture-detecting subsystem comprising:
• a tracking solid first element S1 tightly attached to the viewing device Dv;
• a fixed solid second element S2 tightly joined to the reference device Df, and
• a means for measuring and determining the relative orientation {circumflex over (K)} of the tracking mobile first element S1 with respect to the fixed second element S2,
• a dual harmonization subsystem for harmonizing the worn/borne head-up viewing system and the DDP posture-detecting subsystem,
• the dual harmonization method being wherein it comprises steps consisting in
• in a first step, a series of a preset number N of measurements of relative orientations {circumflex over (K)}l, i varying from 1 to N, of the tracking mobile first element S1 with respect to the fixed second element S2 of the DDP posture-detecting subsystem, corresponding to different targeting actions Vi, i varying from 1 to N, are carried out, in which measurements one or more different preset elements of pilot/driver information displayed in the viewing device Dv are superposed or aligned with one or more corresponding landmarks of the real outside world the theoretical rotation matrices Ûi of which in the exterior reference coordinate system are known;
• then
• in a second step, and using a dual harmonization algorithm, conjointly calculating the relative orientation matrix {circumflex over (R)}(S1/v) of the tracking first element S1 of the posture-detecting subsystem with respect to the viewing device Dv and/or the relative orientation matrix {circumflex over (R)}(ref/S2) of the external reference device DRef with respect to the fixed solid second element S2 of the posture-detecting subsystem to respectively be the right-side bias rotation matrix {circumflex over (D)} and the left-side bias rotation matrix Ĝ, which are conjoint solutions of the system of dual harmonization equations:
• Ûi=Ĝ·{circumflex over (K)}i·{circumflex over (D)}, i varying from 1 to N.