Systems and methods for camera modules having a movable lens barrel, allowing a maximum lens diameter with minimal outside dimensions are disclosed. At least one single linear actuator is moving the lens barrel. Each actuator is deployed in an own corner of the camera module. The moving lens barrel is guided by rolling elements bearings. The actuator comprises a stator, comprising one or more coils wrapped around a rod of magnetic metal and an anchor comprising one or more permanent magnets, which are tightly attached to the lens barrel. An offset between the longitudinal center line of magnets of the anchor and the center of the stator generates a permanent force pushing the lens barrel in direction of the stator of the motor and consequently pushes protrusions on the lens barrel onto the rolling elements bearings, thus preventing the bearings to fall apart in case of a mechanical shock.