APPARATUS AND METHOD OF CONTROLLING MOTION AND VIBRATION OF A SENSOR IN A DRILLING ASSEMBLY

摘要

A system for controlling sensor motion during a time-dependent measurement, comprising a drilling assembly (100) having a drill bit (106) at one end and engaged with a drill string (102) extending to a surface location at an opposite end thereof. A sensor (113) is disposed in the drilling assembly (100) for making a measurement of a formation parameter of interest. A non-rotating stabilizer (126, 127) is disposed in the drilling assembly (100) proximate the sensor (113). The non-rotating stabilizer(126, 127) is adapted to reduce motion of the sensor (113) below a predetermined level during the measurement. In one embodiment the rotational axis of the stabilizer is eccentric with respect to the borehole (128). In another embodiment, the non-rotating stabilizer (126, 127) has an extendable rib for changing the effective diameter of the stabilizer.