Robustify Ulanding Radar #24333
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Robustify Ulanding Radar #24333
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The current implementation of the Aerotenna uLanding radar driver assumes that the UART frames are received in full. If the driver polls with 10ms this is not always the case and the driver will fail to parse the frame leading to significant packet loss. This workaround polls at 12ms which ensures that at least one entire frame is received.
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Solved Problem
We measured 50%-100% message drop, which could lead to repeated timeouts.
The issue was that the driver is written with the assumption that the entire message is received.
However the sensor sends a message every 10ms and when the driver samples every 10ms, only parts of the message will be received.
Solution
This workaround fixes this by setting the sample rate to 12ms, since 11ms still had single digit message drops.
Alternatives
The driver would have to be rewritten as a proper state machine to find the full message. For now this fix is sufficient.
Test coverage
Context
The sensor does not perform byte stuffing, thus the header must be searched together with the CRC.