A study of the mechanics and restoration for the South-Pointing Chariot was conducted.Firstly,the history of a manufacturing of the South-Pointing Chariot was considered. Secondly,the pattern of the South-Pointing Chariot is replaced with the combined planetary gear system in which two simple planetary gear trains are connected.Thirdly,through theoretical analysis,it is clarified that power circulation occurs in the system.Thus the principle that fulfills the fundamental function of the South-Pointing Chariot is explained.Fourthly,it is confirmed that this analyzing method could be applied to the mechanical variable-speed drive which uses the combined planetary gear system. Then.a restorative design and manufacture of the South-Pointing Chariot is carried out.The theories in this analysis are verified by a practical test run of the Chariot. A study of the mechanics and restoration for the South-Pointing Chariot was conducted. Firstly, the history of a manufacturing of the South-Pointing Chariot was considered. Secondly, the pattern of the South-Pointing Chariot is replaced with the coupled planetary gear system in which two simple planetary gear trains are connected.Thirdly, through theoretical analysis, it is clarified that power circulation occurs in the system.Thus the principle that fulfills the fundamental function of the South-Pointing Chariot is explained. Fourthly, it is confirmed that this analyzing method could be applied to the mechanical variable-speed drive which uses the combined planetary gear system. Then. a restorative design and manufacture of the South-Pointing Chariot is carried out. The theories in this analysis are verified by a practical test run of the Chariot.