Patent ID: 7228253
Filing Date: 2007-06-05
Classification: G02B

Abstract:
1. An apparatus for positioning an instrument, the apparatus comprising: (a) a motor shaft adapted to receive torque from a motor; (b) a rotatable instrument coupled to an instrument shaft for rotation therewith, (c) a linkage between the motor shaft and the instrument shaft, the linkage having alternative first and second operating modes, wherein: (d) a motor shaft position detector (“MSP detector”) operable to generate a motor shaft position signal (“MSP signal”) responsive to an angular position of the motor shaft about a motor shaft axis; (e) an instrument shaft position detector (“ISP detector”) operable to generate an instrument shaft position signal (“ISP signal”) responsive to an angular position of the instrument shaft about an instrument shaft axis; and (f) a controller coupled to receive the MSP signal from the MSP detector and to receive the ISP signal from the ISP detector and configured to determine an angular position of the instrument as a function of the MSP signal and the ISP signal and to operate the motor to position the instrument based at least in part on the determined angular position of the instrument.