Based on an analysis of the relative shaft-to-hole position and attiude errors, as well as of the mechanics and Kinematics in the process of automatic assembly of industrial robots, the paper studies the principle of construction of dynamic wrists.

They are most likely caused by irregular movements in playing badminton and tend to appear in the wrists and the shoulder joints.

As far as the basic piano playing skills are concerned,the following points should be paid attention to: the support from fingers to palms will affect the quality of sound produced;wrists are the key parts which not only connect lower arms to fingers,but also function as an adjustor;elbows act as media in piano playing;and in addition,the use of the natural weight of arms is of extreme importance.

Objective To explore the maturition of individual bones of the hand and wrist in girls with Turner syndrome (TS).

Objective The age estimated by skeletal age of hand and wrist were compared between different standards in adolescent,in order to observe the effects of secular trend of skeletal development to age estimation.

This study included three parts as follows: PartⅠanalyzed the growth of hand-wrist in Tianjin adolescents and compared with the CHN standard.