Initializing GyroSensor after each start of an app

[peehrlich2]

As I noticed, the gyro sensor is initialized shortly (1-2 seconds) after starting an app. That means, that the Robot has to stand absolutely still a few seconds after each start of an app - otherwise there is the feared GyroDrift.
If you go to a competition it would be very helpfull, when the GyroSensor is automatically initialized once when ev3rt is booting. Perhaps the Sensor Configuration can be arranged in rc.conf.ini?

[JakubVanek]

Well, it depends. In Robosoutěž (a robots competition taking place at CTU FEE in Prague, Czechia), each team has got one minute of preparation time specifically for sensor calibration before the start of each round. So I got used to having a calibration step in the program startup procedure that asks the user to put the robot on the start tile, confirm it on the brick and then let it rest for a second.

You can trigger a manual recalibration of the sensor by running ev3_gyro_sensor_get_rate() and ev3_gyro_sensor_get_angle() after one another.

An alternative might be to use only the rate of rotation from the gyro and do the calibration and integration in software. That could allow one to implement better or continuous calibration without delays; however I have no experience with it. Something like leJOS' LinearCalibrationFilter or GyroDirectionFinder could serve as a base.

[JakubVanek]

I'd also recommend calling a to-be-used value read function for each sensor at the beginning of each program - that will pre-configure the sensor into the correct mode.