A Computationally Efficient GNSS/INS Design of Multirotor based on Error-state Kalman Filter

This paper presents a GNSS/INS based on an error-state Kalman filter (ESKF) to combine the global navigation satellite system (GNSS) and inertial navigation system (INS) for multirotors. The onboard sensors consist of an inertial measurement unit (IMU), a magnetometer, a GNSS receiver, and a rangefinder. The proposed system can estimate the position, velocity, quaternion, and IMU bias, where the INS design significantly improves the positioning update rate of the GNSS. In addition, to execute the algorithm on flight computers with restricted computational resources, a code generator is developed to utilize the sparse and symmetric structure of the ESKF, which can produce high-efficient C code to speed up the computation time.