ESA GNC Conference Papers Repository

Honeywell unveiled the 3-axis HG4934SRS, a Micro Electro-Mechanical Systems (MEMS) based Inertial Reference Unit (IRU) in 2019. Since introducing the new IRU, Honeywell qualified and delivered the IRU to many customers. Development of the HG4934SRS addressed the needs of the growing small satellite market with its advantageous Size, Weight, Power, and Cost (SWAP-C). The Space Rate Sensor?s development maintains Honeywell?s leading gyro performance while also establishing a robust design for the space environment. The product?s reference design mission, a 6-year polar Low Earth Orbit (LEO) mission, its radiation environment, and its influence on the product?s design are presented. It also presents results of system level Total Ionizing Dose (TID) and Single Event Effects (SEE) analysis and qualification. During development, a detailed radiation shielding model of the HG4934SRS was created using the NOVICE code to facilitate analysis and generate accurate dose predictions for different orbits and installations. Environmental and Electro-Magnetic Interference (EMI) qualification test results are shared for the design. Every HG4934SRS goes through a suite of acceptance tests, the details of which are highlighted. Lastly, the results of reliability analyses are presented.