The existing suite passed both before and after the fusion fixes, so it
never covered either failure. Two tests close that gap; both were checked
against the pre-fix sources and fail there.
calibration_offset_test reproduces the bench part's +28 mg zero-g offset
and requires startup to complete, while still refusing a sustained 3 m/s2
acceleration. It also asserts the blind spot rather than leaving it
implicit: horizontal acceleration adds to gravity in quadrature, so
1.5 m/s2 moves the magnitude by only 0.11 m/s2 and is not separable from
offset by any accelerometer gate. Separating it needs GNSS velocity.
long_outage_trajectory_test drives pedestrian, gentle-car (0-100 km/h in
30 s), slow-city and isolated-mount profiles across 1 and 5 minute
outages, using the production rest supervisor rather than a hand-set
flag. Only the isolated-mount slow-city case reproduces the field bug:
GNSS motion evidence compares displacement against covariance, so 4 m/s
under 6 m sigma scores a displacement NIS of 0.22 against a 9.21 gate and
reads as stationary, whereas highway speed scores 42.9 and is correctly
called moving. Pre-fix that case produces 608 zero-velocity updates while
driving, matching the 609 in the board logs.
Drift is judged against the filter's own covariance rather than a fixed
distance. Five minutes unaided legitimately reaches kilometres on this
hardware; what must not happen is the error outrunning the covariance,
which is divergence rather than honest coasting.
tdk_noise_test characterises the sensor at rest through the production
driver, so ODR, full scale, UI filter and LSB scaling match the flight
build, and reports the norms fusion_motion_update() actually gates on.
It also carries an INT1-to-PLIC continuity test that drives the pin to a
static level and reads the PLIC pending bit directly, separating a broken
line from a source that never fires.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
onur cayan