Seed the mag heading anchor with Vancouver declination - #66
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Set offset_seed_deg to -15.5 (Vancouver magnetic declination ~15.5 deg E; the measurement asserts heading + offset = -yaw, so a true-north heading needs offset = -declination). This fixes the declination term of the pre-GNSS heading; boat iron and the BNO-to-boat frame constant still need GNSS to refine, so heading is not absolutely correct until a fix arrives (or a persisted offset is restored at boot, a planned follow-up). The boot-anchor sim test models a zero-declination field, so it pins the seed to 0 for that world. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Sets the boot-time mag heading anchor (
mti_yaw.offset_seed_deg, added in #65) to Vancouver's magnetic declination so the pre-GNSS heading is roughly true-north instead of magnetic-north.offset_seed_deg = -15.5: the measurement assertsheading + offset = -yaw, so a true-north heading needsoffset = -declination(Vancouver ~15.5 deg E, 2026).Follow-up worth doing (not here): persist the GNSS-refined offset to flash and restore it at boot, so a reset recovers the full offset (declination + iron + frame) immediately rather than coasting to a static guess.
Verification: 208 sim + native fusion tests green;
pico2builds.