QIU Zu-rong, SUN Qian-hui, LIU Jia-chen, XUE Jie, SU Zhi-kun
(State Key Laboratory of Precision Measuring Technology and Instruments, Tianjin University, Tianjin 300072, China)
Abstract： Under the premise of fully respecting Technical Leaflet T3 developed by the International Table Tennis Federation (ITTF), this paper proposes an effective method for testing the veer degree of the table tennis ball based on airflow suspension and machine vision. By sequentially capturing the images of the ball in the stable state of spinning and suspension, a set of fitting circle centres from different circular sections can be obtained by circle fitting through the least square method. The minimum circumscribed circle (MCC) diameter of these centres is served as a basic parameter to evaluate the veer degree of the ball. Experimental results show that this diameter can effectively reflect the veer degree of the ball. The method proposed in this paper can provide a technical basis for the veer online testing of the table tennis ball.
Key words： table tennis ball; veer; minimum circumscribed circle (MCC)
CLD number： TG806Document code： A
Article ID： 1674-8042（2017）01-0001-08 doi： 10.3969/j.issn.1674-8042-2017-01-001
References
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乒乓球偏心检测方法
裘祖荣， 孙芊慧， 刘佳琛， 薛洁， 苏智琨
（天津大学 精密测试技术与仪器国家重点实验室， 天津 300072）
摘要:在充分尊重现行国际乒乓球联合会制定的新T3标准的前提下， 提出了一种基于气流中悬浮和机器视觉的乒乓球偏心的检测方法。 该方法通过多次有序摄取处于悬浮旋转状态的乒乓球图像， 以不同截面圆最小二乘拟合圆圆心点集的最小包容圆直径作为评价乒乓球偏心程度的基本参数。 实验结果表明， 拟合圆圆心点集的最小包容圆直径能有效反应乒乓球的偏心程度。 该方法为乒乓球偏心的在线检测提供了技术基础。
关键词:乒乓球； 偏心； 最小包容圆
引用格式：QIU Zu-rong, SUN Qian-hui, LIU Jia-chen, et al. Testing method for veer of table tennis ball. Journal of Measurement Science and Instrumentation, 2017, 8(1)： 1-8. ［doi： 10.3969／j.issn.1674-8042.2017-01-001］
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