Robust GPS/INS Solution to Launch Vehicle Guidance, Navigation, and Range Safety Systems

An integrated MEMS GPS/INS design architecture is proposed for the launch vehicle (LV) navigation solution and range safety applications. The proposed concept consists of three major elements: 1) GPS/INS hardware architecture, 2) GPS/INS software architecture, and 3) robust filtering scheme. The hardware architecture design will be evaluated and down-selected from three major MEMS vendors using our high fidelity simulation environment while the software design architecture is selected implemented in such a way that it optimally provides the right data format and accuracy to meet range safety minimum requirements for the LV GPS receiver Data for the Space Lift Range System. The robust filtering scheme consists of three key features: i) multiple model estimation scheme, ii) the adaptation of the noise statistics via an effective noise identification scheme, and iii) the estimation of both gyro and accelerometer bias vector by using the GPS receiver data as an external aiding sensor to in-flight calibrate the IMU. GPS/INS tightly couples architecture is selected to provide robust navigation solution against poor satellite tracking, data latency, GPS dropout, etc. The proposed concept is capable of 1) correcting the GPS errors via noise identification mechanism and 2) aiding the GPS to reduce acquisition times and velocity errors.