[Awesome-Ace22]

What and why

This pull request adds robust calibration methods for sensor data, improving the system's resilience to outlier calibration points. It introduces two robust line-fitting methods—Theil-Sen and Siegel's repeated median—and integrates them into the calibration pipeline. Comprehensive tests are also included to ensure correctness and reliability of the new methods.

Robust calibration methods:

• Added THEIL_SEN and REPEATED_MEDIAN options to the ConvertMethod enum in app/models.py, enabling selection of robust linear fitting methods.
• Implemented robust line-fitting functions (theil_sen_fit, repeated_median_fit) and a unified robust_interpolate function in app/services/data_service.py, allowing calibration to ignore outliers and improve accuracy.
• Updated the main sensor value conversion logic to use the new robust methods when selected, ensuring robust calibration is applied throughout the codebase.

Testing:

• Added a new test suite tests/test_robust_calibration.py with extensive test coverage for the robust calibration methods, including edge cases and integration with the sensor parser.

Codebase improvements:

• Refactored imports and code structure in app/services/data_service.py to support the new calibration methods and maintain clarity.

How was this tested?

• 1 Unit / Automated Test - CI
• 2 Simulator Test - testing procedure with the hardware simulators
• 3 Bench Test - testing procedure on the dev stack, with some real hardware
• 4 Integration Test - full engine test procedure, real hardware, no propellants

Hardware impact

• None - UI, docs or tooling only
• Changes how a sensor is read, converted or shown
• Changes how an actuator is commanded, or safety rules, interlocks, timeouts or sequencing → add the hardware-risk label; a lead must approve
• Changes a message format, MQTT topic or FAS protocol that another repo depends on → title needs !, link the matching PRs:

Checklist

• Targets dev (or main for a release/hotfix, or with a reason given above)
• Branch is up to date ("Update branch" button)
• No station config/calibrations, data files, secrets, .env files or build output committed
• README/docs updated if behaviour changed