Study on Error Analysis of Measuring Projectile's Speed Using Induction-Type Coil Target

We presented the basic principle of projectile's speed measurement based on inductive coil, and the main sources of error related to the geometric distance and timing measurement. The physical and mathematical model of induced electromotive force was established while one magnetized projectile flying through the coil target. Furthermore, we propose the concept of the physical effective distance, and discuss some errors generated by physical factors. Due to the difficulty to measure the physical effective distance, a simple calibration method was introduced. Error reduction factor formulas were analyzed to show the effects through calibration in details, considering the effects of both system and random errors. Through the given calibration method, the measurement error of coil targets can be reduced.