Microtechnology is a valid means of discriminating between tackle and carry performance. Thus, microtechnology-derived collision load data can be utilized to track and monitor collision events in training and games.

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This paper presents a new alignment transfer method which uses only accelerometer measurements in the gravitational field. The TRIAD (Three-Axis Attitude Determination) algorithm is rcformulated to use two pairs of gravitational measurements instead of star observations to achieve three-axis attitude determination. A major benefit of the method is the freedom to choose missile Inertial Measurement Unit (IMU) gyros based solely on in-flight considerations. An additional benefit is the ability ta update the alignment transfer by simply making new measurements of gravity and reprocessing the measurements taken before erection. This new alignment transfer method eliminates 'Time to Complete Alignment Transfer' from the major contributors of the alignment error. Algorithm development, error analysis and laboratory results are provided. INTRODUCTIONAttitude initialization of mobile mllssile systems continues to be a significant cost and time consideration. Self-alignment techniques often call for accurate accelerometers to determine local 1evc:l. A 2-dimensional attitude relationship between an IMU and a local level coordinate system can be solved using accelerometer measurements in the gravitational field However, the accelerometers -do not provide information about the aximuth orientation of the IMU. Therefore, highly accurate gyros are needed to determine azimuth. However, even highly accurate gyros need significant time, urlually measured in minutes, to achieve the desired azimuth accuracy. These drawbacks of self-aligned systems resulted in a division of the azimuth determination problem into two parts. A highly accurate (i.e. expensive) inertial measurement unit (Master IMU) is CO-located on the launch erection structure. This master IMU is initialized before the erection of the missile. The erection motion is then used to determine the relative attitude between the master IMU and the less accurate missile IMU (i.e. less expensive).This attitude correction is then uploatled to the missile IMU. The alignment accuracy is uansfemd from the master [MU to the missile IMU with only modest degradation resulting from inaccuracies in the determination of the attitude correction. The evolution from self-alignment to alignment transfer has relied on gyro based measurements to determine attitude for mobile ground launched missile systems.Typical azimuth alignment transfer schemes match the attitude measurements of the missile and master IMUs resulting from the launcher erection to determine the azimuth attitude correction to be uploaded to the missile. The use of attitude matching calls for accurate gyros in the missile IMU since a major error contribution comes from: (1) Equation 1 and other alignment transfer related error sources have caused the accuracy needed by the missile IMU gyros to be driven more by initialization requirements than by in-flight considerations. Therefore, it is highly desirable to use only accelerometer measurements 110 accomplish alignment transfer. This paper provides such an alignment transfer op...