What is sensor fusion in the context of an IMU?

• A. Combining data from accelerometer, gyro, and magnetometer to estimate orientation.
• B. Averaging accelerometer data only to measure acceleration.
• C. Using GPS data to estimate orientation.
• D. Only using one sensor at a time for orientation.

Answer: (A)

Sensor fusion is the process of combining measurements from multiple sensors to produce a more accurate estimate of something, like orientation, than any one sensor could provide alone. In an IMU, each sensor gives different information: the gyroscope measures angular velocity and, when integrated, tracks orientation but drifts over time; the accelerometer points toward gravity and helps stabilize pitch and roll but is noisy and can be thrown off by actual movement; the magnetometer provides heading relative to Earth's magnetic field but can be distorted by nearby metal and electronics. By fusing these signals with a filtering method (such as a Kalman or complementary filter), the system weighs each sensor’s information by its reliability and blends them to yield a stable, accurate orientation estimate. Relying on a single sensor or using data like GPS for orientation doesn’t provide the robust result that sensor fusion offers.