I am trying to build a quadcopter and think it is essential to have its center of mass in the middle. Therefore, I am planning on putting the battery in the center. However, this will cause me to place my gyroscope/accelerometer sensor not in the center. Will the sensor data be not useful if the sensor is placed away from the center of mass of the quadcopter? Should I put the sensor in the center of the drone and place the battery with a slight offset from center? Also if the sensor data can be used no matter where it is placed, would it require a lot of math to transform the data to something useful for control?
Most quadcopters position the flight controller/sensors at the center with the battery slightly above or below but still on the center.
If you are planning on building a race quad that will not use auto level, then you can place your gyro anywhere as the roll rate will be measured the same (just ensure that you set the orientation parameter properly in its settings).
If you are planning on using auto level, then you should put the sensors in the center, as auto level requires accelerometers which need to be at the center of mass for the highest accuracy.