| 摘要 |
PROBLEM TO BE SOLVED: To appropriately reduce noise while suppressing time lag of an output signal even when a measurement signal by a load cell is rapidly changed.SOLUTION: An observation noise parameter calculation unit 13 calculates a standard deviation of a plurality of measurement signals obtained when calibrating a device having no test piece mounted thereon and stores it in a storage unit 14 as a parameter &sgr;relating to the observation noise. During executing the measurement, a processing noise parameter calculation unit 12 acquires a gradient of the change based on a prescribed number of latest data values and assigns it to a Kalman filter 11 as a parameter &sgr;relating to the processing noise. The Kalman filter 11 executes a correction based on an error between a state estimation using the parameters &sgr;and &sgr;and an actual measurement signal to smooth and output the measurement signal. The parameter &sgr;is dynamically changed according to a change in the measurement signal so as to appropriately reduce the noise while substantially following to the rapid change in the measurement signal. |
