A downhole tool for use in a well bore comprises an onboard navigation
system for determining the location of the tool within the well bore,
wherein the tool is moved along at least a partial length of the well
bore via an external force. A method of locating a downhole tool in a
well bore comprises deploying the tool along at least a partial length of
the well bore via an external force, and self-determining the location of
the tool without receiving communications from the surface. In an
embodiment, the tool is a well bore zonal isolation device.