Compact Precision Space IMU

Phase I demonstrated key technologies and development work for the Rad Hard frac12; U Compact Precision Inertial Measurement Unit (CIMU).nbsp; Optimized gyro bias compensation including switched drive achieving navigation grade performance using a commercially available TRL9 piezo-transduced Coriolis Vibratory Gyroscope (CVG) sensor integrated with IWrsquo;s digital IWAG control algorithm demonstrated rate noise necessary to attain Attitude Determination with lt;0.1 arc second pointing and arc second level control.nbsp; IW further demonstrated navigation grade north-finding capabilities with a representative IMU block mounted CVG.nbsp; Temperature testing and optimization of thermal bias compensation was also demonstrated.IW successfully replaced the bulky discrete analog CVG controller electronics with IWrsquo;s digital-based low noise ASIC using IWrsquo;s patent pending embedded IWAG control algorithm.nbsp; Full digital closed loop Rate Gyro operation with excellent bias stability was demonstrated.nbsp; Efficacy of IWrsquo;s Radiation Hard by Design (RHBD) method in the ASICrsquo;s CMOS process was demonstrated with successful Mega-Rad level Co60 chamber testing of IWrsquo;s sensor analog front-end (AFE).nbsp; Significant analysis and simulation of Single Event Effects and efficacy of planned SEE hardening for the full RHBD ASIC in planetary orbit and interplanetary radiation environments was completed.nbsp;A full mechanical design and FEA analysis and system design of the IMU was completed with integrated 3-axis ASIC-based CVGrsquo;s, COTS MEMS accelerometers, interface electronics, and mechanical assembly.nbsp; Mechanical modes and thermal characteristics were verified, with more work planned for vibration isolation in Phase II.nbsp;Phase II will design and fabricate a complete RHBD version of the CVG ASIC control.nbsp; We shall then integrate it to resonators and build and test the complete CIMU, achieving significantly smaller size, lighter weight, and much lower power than state-of-the-art space IMUs (e.g. MIMU, SIRU).