ENH: seed the rocket sensors from the scenario seed (closes #52) - #54
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Thread the scenario seed into the gyroscope / accelerometer / GNSS sensors via the new ActiveRocketPy sensor seed argument (#13). Each sensor gets a decorrelated sub-stream from SeedSequence([np_random_seed, domain]).spawn(3), clear of the balloon Monte Carlo seed tree, so the noisy-sensor observations are reproducible from the announced scenario seed and independent of the global RNG. Bumps the ActiveRocketPy submodule to develop (e9ebff65), which carries the seed support; adds tests/test_sensor_determinism.py. Closes #52.
zuorenchen
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LGTM, but let's wait for the changes in ActiveRocketPy on main then merge this
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A launched rocket currently cannot be packed for submission. pack_for_submission runs the flight through RocketPyEncoder, the flight carries the rocket, the rocket carries its sensors, and a sensor hands back the seed it was built with. Since #54 that seed is a SeedSequence, which the encoder cannot serialize, so packing raises TypeError: Object of type SeedSequence is not JSON serializable. Both scenarios are affected even though their sensors are noise free, because the object is stored regardless. Derive a plain 128-bit int from each spawned child instead. The domain separation and the per-sensor decorrelation are unchanged, and with noise-free sensors the trajectories and scores are identical, which both golden masters confirm. Also stop Gymnasium's unknown-seed marker from crashing the launch: np_random_seed is -1 when np_random was assigned directly, and SeedSequence rejects negative entropy. Draw the entropy from the generator in that case. Signed-off-by: thc1006 <84045975+thc1006@users.noreply.github.com>
This was referenced Jul 28, 2026
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Closes #52.
Now that the sensor
seedargument from ActiveRocketPy #13 is merged, this threads the scenario seed into the rocket's IMU and GNSS sensors, so the noisy readings come out the same for a given scenario seed and don't depend on the global RNG. Each sensor gets its own sub-stream fromSeedSequence([self.np_random_seed, domain]).spawn(3), with a domain tag that keeps it clear of the balloon Monte Carlo's seed tree so the two can't collide (even if the MC ever runs in parallel).Scenarios #0 and #1 use zero-noise sensors today, so none of the current baselines change. It starts to matter once a noisy-sensor scenario lands (the #2 line in #45).
One thing to check on the submodule: this moves the
ActiveRocketPypin from master (6f640a1) to develop (e9ebff65), since #13 lives on develop. Develop already has the actuator module, so the physics is unchanged, and I ran the full BPC suite (15 passed) plus the determinism tests against it. If you'd rather keep BPC on ARP master, we can release develop to master first and pin that instead. Either way BPCmaincan keep tracking ARP releases.Tests are in
tests/test_sensor_determinism.py: same seed reproduces the stream, different seeds differ, and the noise doesn't depend on the global RNG. Checked locally the way CI does (ruff check,ruff format --check,pytest tests/), all green on 3.14.