OpenMarine
Wind instrument computer with IMU, for accuracy and rotating masts? - Printable Version

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Wind instrument computer with IMU, for accuracy and rotating masts? - fugue137 - 07-24-2019

The masthead is a great spot for wind instruments, but there are two problems:
  1. Masthead motion in light air and a swell creates large shifts in apparent wind
  2. Rotating masts: how to measure rotation and introduce the correction to wind direction?
One possibility for (1) is to put accelerometer/gyro on the mast, and use it to compensate for accelerations. Since accelerometer/gyro seem to usually include a magnetometer, that allows a good solution to (2) at the same time, with the simple addition of a compass in the hull, which PyPilot requires anyway (i.e. compare the 2 compasses and add the difference to wind direction). So: does the Weather Sensor (e.g. https://pypilot.org/store/index.php?rt=product/product&product_id=126) have an IMU sensor? Based on the price I don't see how it could! But perhaps it has room for an mpu9255 (https://pypilot.org/store/index.php?rt=product/product&product_id=129)?

I had been thinking along the lines of a standalone rotating-mast-correcting wind computer that talked to a wind instrument and hull and mast compasses, and output corrected NMEA0183 relative wind sentences. That would be generally useful---easy to integrate with any electronics in existence rather than just OpenPlotter. What do you think about offering an mpu9255-added version of the wind computer? Can I do this myself and still use your enclosure and code as a starting point?

Thanks!