Ball throwing machine and target net
作者： Jay E Cook
DOI:
关键词: Computer science 、 Mechanical engineering 、 Ball (bearing) 、 Throwing
摘要:
lens.org 参考文章(4)
George H Perryman, Table tennis player ,(1938)
Earl G Strong, Ball return means for bowling alleys ,(1949)
Jay E Cook, Ball return and throwing device ,(1953)
Jay E Cook, Ball throwing machine ,(1953)