Marco Polo: Finding a friend with only distance and motion
Summary
Marco Polo discusses finding a friend with only relative distance and motion using two microcontroller-based beacons with IMU and UWB sensors. The post analyzes options: multi-antenna UWB with time-of-flight, phase differences (PDoA), external trilateration with anchors, and Kalman Filter-based solutions (EKF) for bearing estimation using a nonlinear state-space model. It walks through implementing an EKF, defining the state vector, the prediction and measurement steps, and how bearing is extracted, ending with a demo and further reading.