| 摘要 |
According to aspects of the present disclosure, systems and methods for a closed-loop speed/position control mechanism. An example system may include a housing and a planetary gearbox disposed within the housing, wherein a ring gear of the planetary gearbox is coupled to the housing, a sun gear of the planetary gearbox is coupled to a drive shaft, and a planetary carrier of the planetary gearbox is coupled to an output shaft. A controller may receive measurements from sensors proximate to the output shaft and use those measurements to transmit control signals to change the rotation of the drive shaft. In this way, the output shaft may be rotated independently of the housing by controlling the rotation of the drive shaft. In example systems, the output shaft may be a sonde or an offset mandrel coupled to a drill bit. The rive shaft may be coupled to a fluid-controlled controlled drive mechanism and rotation may be controlled by adjusting flow control valve. The closed-loop system may be used to set a target rotation speed of said output shaft or may be used to maintain the output shaft in a constant position or orientation despite housing rotation. |
