Using low-cost MEMS accelerometers and gyroscopes as strapdown IMUs on rolling projectiles

Low-cost, micromachined, inertial sensors have been steadily emerging into the commercial marketplace. Some of these commercial off-the-shelf (COTS) sensors were evaluated for their insertion potential into military applications such as test and evaluation (T&E) and smart munition guidance. Performance requirements to provide time, space, position, and attitude information (TSPAI) and allow for navigation capabilities are fast approaching those needed, especially when integrated with a global positioning system (GPS) receiver. Artillery projectiles and rockets, instrumented with commercially available low-cost microelectromechanical systems (MEMS) accelerometers, spin sensors, and custom telemetry units, have been flight tested with good success. Test results suggest that many of these sensors are rugged enough for launch survivability and subsequent operation. Analysis of the accelerometer flight data shows good agreement with ground-based radar and other truth measurements. Ground tests of a MEMS gyroscope on a ballistic flight simulator have also been conducted. The results show promise for directly measuring a projectile's pitching and yawing behavior. This paper will present some of the test results and describe the challenges far using these devices as strapdown inertial measurement units (IMUs) on rolling projectiles.