Fiberscope is a tool, which is used for inspecting holes and cavities. The basic unit of operation is a flexible tube that can change its view angle or navigation through paths that are not straight. Important specifications for fiberscopes include tube or sheath diameters, working length, field of view and minimum focus distance.  The tube diameter is the diameter of probe for insertion into the cavity to be inspected.  This typically determines the minimum size hole the scope can be used with.  The working length is the length of the probe.  This effectively determines depth of inspection capability.  The field of view is the viewing cone included in the viewing angle.  It is a measure of how much of the visual field is taken up by the image.  The minimum focus distance for the fiberscope is the minimum effective focusing distance. A robotic probe is a device that uses onboard instruments to gather and relay a variety of telemetry to controllers from remote, hazardous or otherwise difficult to reach locations. Probes may return their data over radio links or be physically tethered to controllers or another device, or to collect and return physical samples.