Shafting structure design in a 600 mm thin mirror active optics telescope

An alt-azimuth shafting structure with high precision standard bearings was designed for a 600 mm scaled down model telescope system, which is for studying the large telescope thin mirror active optics technology. It has more benefits including quick installation and adjusting, high interchangeability, and easy maintenance. The altitude shafting is consisted of a pair of radial angular contact ball bearings. The azimuth shafting is consisted of thrust ball bearing and double-row cylinder roller bearing. The lowest three order natural frequencies and the modes were resolved by the finite element simulation software Patran. The error sources were analyzed, which are mainly affecting the shafting rotating accuracy. The measuring results were processed by harmonic theory and it shows good performance in the altitude shafting wobble error of 4.2 , and the azimuth shafting wobble error of 9.3. Desirable imaging was got in the stars observing test at the testing field. The design can prove reliability of the shafting structure, and offer a reliable guidance and advanced path for developing the high precision shafting of medium and small sized telescope.