Modern Robotics Gyro Sensor Warning: Problem with "gyro"

[Bionic Enforcers Rep.]

My team is using the Modern Robotics Gyro Sensor. Whenever we use the gyro sensor, we see an error on the driver station that says Warning: Problem with "gyro". We checked our configuration and we put it in the 12C, and we selected MR Gyro. Also we heard the gyro was supposed to light up blue when we initialize the robot. We know that this problem is a problem with the driver station, but we do not know how to fix it. Does anyone know how we can solve this problem?

[3805Mentor]

Did you plug the level shifter and adaptor cables in the right way?

The big question is why are you using the Modern Robotics Gyro. There is a gyro built into the Rev Hubs. The example program shows how to use it.
Our team's MR gyro was not a very good sensor, it had a lot of drift, we don't know if that was common. We went to the Adafruit Bno055 gyro which worked much better, then the Rev Hubs came out and they have the Bno055 gyro built in.

[jkenney]

To expand on what 3805Mentor said: while it's physically possible to plug the MR gyro directly into the Rev level shifter, that won't work. You need to use an adapter cable that switches the SCL and GND wires.

Also agree there's no reason to use that sensor if you just want to know the robot's heading. But we have mounted it on an arm to monitor it's position (when the arm motor encoder wasn't working).

[Bionic Enforcers Rep.]

Did you plug the level shifter and adaptor cables in the right way?

The big question is why are you using the Modern Robotics Gyro. There is a gyro built into the Rev Hubs. The example program shows how to use it.
Our team's MR gyro was not a very good sensor, it had a lot of drift, we don't know if that was common. We went to the Adafruit Bno055 gyro which worked much better, then the Rev Hubs came out and they have the Bno055 gyro built in.

If we wanted to use the rev hub built in gyro sensor would we use the SensorBNO055IMU and SensorBNO055IMUCalibration programs.

[jkenney]

If we wanted to use the rev hub built in gyro sensor would we use the SensorBNO055IMU and SensorBNO055IMUCalibration programs.

Yes, the SensorBNO055IMU example demonstrates its use. We've had great results without ever having to resort to using the SensorBNO055IMUCalibration program.

If you plan to mount the Rev hub vertically (or upside down), then you may need to change the axis configuration and/or axis sign, which is not addressed in the example op mode, but which is discussed in this old thread.

[Bionic Enforcers Rep.]

Yes, the SensorBNO055IMU example demonstrates its use. We've had great results without ever having to resort to using the SensorBNO055IMUCalibration program.

If you plan to mount the Rev hub vertically (or upside down), then you may need to change the axis configuration and/or axis sign, which is not addressed in the example op mode, but which is discussed in this old thread.

Is the configuration for the imu on port zero

[jkenney]

Is the configuration for the imu on port zero

The BNO055 chip in the Rev hub is hard-wired into I2C port 0. So in your config file, you'll want to add a BNO055 device to port 0. To make it compatible with the example op mode, name it "imu".

[Bionic Enforcers Rep.]

The BNO055 chip in the Rev hub is hard-wired into I2C port 0. So in your config file, you'll want to add a BNO055 device to port 0. To make it compatible with the example op mode, name it "imu".

If we are using two expansion hubs would we put add it in the config file for both or just one?

[jkenney]

If we are using two expansion hubs would we put add it in the config file for both or just one?

Only one is necessary. I think that if you are using two Rev hubs, and you create a configuration and scan for attached devices, the system will automatically create entries for both hubs: "imu" in one hub, and "imu 1" in the other. But you should check to be certain.