There are special trains with measurement equipment on board, but yes, it sounds to me like every train should be equipped with some basic sensors for anomaly detection.

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1718627440 5 hours ago | parent [-]

The measurement trains drive slowly in the night.

	▲	Azrael3000 5 hours ago \| parent [-]
		Not necessarily, the measurement train my company develops can go up to 100 km/h and measure certain rail features every 5mm at that speed.