US Patent 11566702 Derailleur shifting system

A derailleur shifting system comprise a front derailleur, a rear derailleur, an operating device and a controller. The front derailleur is configured to be controlled to shift among front gear positions. The rear derailleur is configured to be controlled to shift among rear gear positions. The operating device is configured to generate an operational instruction associated with one or both of the front derailleur and the rear derailleur. The controller is configured to control one or both of the front derailleur and the rear derailleur to shift according to the operational instruction, an estimated gear position table and a gear position control table. The estimated gear position table comprises an estimated front gear position of the front derailleur and an estimated rear gear position of the rear derailleur, and the gear position control table comprises matching relationships between the front gear positions and the rear gear positions.