Calibration Method for Light Screen-Based Speed Measurement Devices for Projectile

Light screen-based speed measurement device for projectile (SMDP) has been widely used by forensic science institutes of public security agencies for firearms identification in China, and it is required be calibrated every year to ensure the speed measurement accuracy and traceability. A calibration method based on multi-channel time delay simulation and live ammunition firing comparison is proposed for calibrating the light screen-based SMDP in this paper. The calibration facilities for dual and triple light screen-based SMDP are specially realized to verify the proposed calibration method. The speed calibration range of the calibration facilities exceeds
$(20\sim1000)\mathrm{m}/\mathrm{s}$
and the maximum permissible error is superior to
$\pm 0.01\ \mathrm{m}/\mathrm{s}$
, which can meet the requirements of light screen-based SMDP for speed calibration range of
$(20\sim1000) \mathrm{m}/\mathrm{s}$
and speed calibration accuracy of
$0. 3\ \mathrm{m}/\mathrm{s}$
. The comparison results of a triple light screen-based SMDP sample validate the effectiveness and feasibility of the proposed calibration method and the realized calibration facilities.