Method for counting restrictions in a subterranean wellbore

A tool for running along a tubular string extending through a subterranean formation, a plurality of radial restrictions spaced along the tubular string, the tool comprising:

• a tool body configured to travel within the tubular string;
• a plurality of mechanical arms movable to extend radially outward from the tool body to an expanded position having an effective diameter greater than the plurality of radial restrictions, each mechanical arm independently movable to a collapsed position when the mechanical arm contacts one of the plurality of radial restrictions and wherein the mechanical arm moves to a collapsed diameter of less than the restriction diameter, each mechanical arm biased to the expanded position;
• a sensor system operable to generate a sensor signal in response to one or more of the plurality of the mechanical arms moving in response to one or more of the plurality of radial restrictions;
• a controller configured to receive the sensor signals, the controller configured to increase a count in response to receiving the sensor signal, the controller configured to generate an activation signal when the count reaches a pre-selected value;
• and
• a radially expandable landing mechanism, movable between a run-in position in which the landing mechanism defines a run-in diameter of less than the effective diameter of the plurality of radial restrictions and a radially expanded position in which the landing mechanism defines an expanded diameter of greater than the effective diameter of at least one of the plurality of radial restrictions.