Do I need gyro sensor to make sure my automower turn 180deg if I already used 9DOF IMU?

Question

I am doing a project to build an autonomous lawn mower and I need to decide several type of sensor to complete the features. one of my features is the vehicles need to stop running when someone held it on the air. so i decide to use 9 DOF IMU for this features.

as i know that 9 DOF IMU already have 3 axes magnetometer that can read the angular yaw position. so i just confused that do I still need to add another gyro sensor to make sure that my lawn mower do a turning 180deg?

Thanks for any words on this.

Answer 1

A 6 DOF IMU refers to 3-axis accelerometers and 3-axis gyroscopes.

A 9 DOF IMU refers to a 6 DOF IMU plus a 3-axis magnetometer.

Since you already have 3-axis gyroscopes in your 9 DOF IMU, adding another gyro sensor would be redundant. You don't need it.