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IMU availability and calibration

Phew! Yesterday evening/night we packed most of the IMU Brick orders, the shipment email should have already been send too.

We are sorry for the long delay! In the future we will make a product that is produced in big numbers for the first time only avaiable in the shop after we have it here and tested. The gyroscope/accelerometer/magnetometer ICs use a Quad Flat No Leads Package (QFN). This means that the pads are below the chip. It is not possible to see solder straps via a visual inspection. For this reason we had problems that lead to more delays (the IMU Bricks had to be X-rayed).

All IMU Brick orders that don’t include a Dual Relay Bricklet should be marked as shipped. We did run short of them unexpectedly yesterday. But that is no big problem, a big batch of new ones are already on there way und they should arrive in the evening today.

With the automatic calibration we had problems to subtract out the magnetic field of the servo motors (this is definitely possible und we will do that in the future). To assure that there aren’t more delays we did calibrate the magnetometers of the first 250 IMUs by hand. The precision did likely suffer, but the magnetometer has to be newly calibrated in most use cases anyway (if the IMU i used near a motor or similar).

And now the announced video:

The hardware is completely based on Sebastian O.H. Madgwick published “gimbal components”. The servo motors and brackets are from servo city and the controlling is of course done with a Servo Brick. The code for the calibration can be found in the IMU Brick git.