Performance data is presented from a MEMS-based IMU being developed at Honeywell with the objective of navigation-grade performance for a variety of applications. Design of the gyroscope is derived from that of the gyroscope in Honeywell's HG1930 tactical-grade MEMS IMU, a widely used tactical-grade MEMS IMU product. Fabrication processes similar to that of the gyroscope are used to fabricate a new vibrating beam accelerometer which measures acceleration via differential frequency change. Turn-on to turn-on bias repeatability better than 0.1 deg/hr for the gyroscopes and better than 20 micro-g for the accelerometers has been consistently demonstrated. Typical gyro ARW of 0.0035 deg/rt(hr) has been achieved, and accel root Allan variance is less than 10 micro-g at integration time of 1 second. The IMU has the same mechanical footprint (though slightly taller) and same electrical interface as Honeywell's HG1930 IMU.
We report performance results on a MEMS outof-plane gyroscope suitable for platform stabilization. Angle random walk (ARW) less than 0.006 deg/rt-hr and median bias stabilities over temperature of 0.2 deg/hr have been achieved. Sensor bandwidth as characterized by drive and sense mode frequency separation is >700 Hz allowing system level bandwidth greater than 300 Hz. The HG6900 IMU will integrate these sensors and serve platform stabilization applications in a 259 cm3 volume.
This paper presents a two die assembly of inertial sensors consisting of three (3) orthogonal gyroscopes and three (3) orthogonal accelerometers which demonstrates tactical-grade performance and occupies a total volume of 112 mm 3 . The sensor mechanisms are identical to existing tactical-grade products while the volume reductions are achieved by combining the sensors into a two-die stack that is wafer-level sealed. Noise floors less than 0.125 deg/rt-hr for gyroscopes and 0.1 fps/rt-hr for accelerometer as well as bias stabilities less than 30 deg/hr for the gyroscopes and less than 10 mg for the accelerometers are reported.
