A device for measuring the variable lateral bow angle and its impact on score loss

During competitions, archers lose points due to errors that vary linearly or quadratically according to the distance to a target. Minimizing the quadratic variables, such as bow cant variation, should result in improvements in an archer’s performance at longer distances in major competitions. Theoretically, a bow cant angle variation of 0.1° from shot to shot can significantly affect an individual’s score. However, this error factor has not been directly measured or observed. Thus, a wireless sensor suite was developed to measure the bow’s movements and confirm that such variations exist. This unit can measure up to 0.05° in multiple orientations and record additional information, such as acceleration at 200 Hz sampling rate. Based on results from experiments with six state-level archers, the wireless sensor system successfully recorded more than 200 shots. From the acquired data, variations were reported from shot to shot. Therefore, it is predicted that an archer may lose up to 23 points per 36 arrows shot using a recurve bow due to this lateral bow angle variation.