Blade positioning and identification system for engine inspection

A method for identifying a plurality of blades of an engine, the method comprising:

• (a) recording a reference view captured by a vision system of a first blade of the plurality of blades at a first blade position;
• (b) comparing, by a controller after displacement of the first blade from the first blade position, information from a view captured by the vision system of another blade of the plurality of blades to information from the reference view;
• (c) determining, from the compared information, if the other blade is at the first blade position;
• and
• (d) generating, by the controller if the other blade is determined to not be at the first blade position, an error signal indicative of an amount an actuator is to be operated to displace the other blade to the first blade position,
• (f) detecting, by the controller using information captured by the vision system when the other blade is at the first blade position, a movement of the other blade;
• (g) determining, if the movement of the other blade is detected, an amount of the movement of the other blade;
• and
• (h) controlling, by the controller, a command to operate the actuator to displace the other blade back to the first blade position, the command being based at least in part on the amount of the movement determined by the controller,
• wherein the detection of the movement of the other blade utilizes vector image subtraction.

A method for identifying a plurality of blades of an engine, the method comprising:

• (a) generating, by a controller, a command to rotate, via an operation of an actuator, a shaft of the engine to position a blade of the plurality of blades at a blade position that corresponds to a reference position at which a reference blade image had previously been captured;
• (b) identifying, by the controller using one or more images captured by a vision system, at least one classifier of the blade, the at least one classifier corresponding to one or more intentional and/or unintentional physical features of the blade that is/are detected by the controller from the one or more images;
• (c) comparing the at least one classifier with stored data for the plurality of blades;
• and
• (d) identifying, from an outcome of the comparison, a stored identifier for the blade;
• and
• (e) repeating steps (a)-(d) until each blade of the plurality of blades is identified;
• and
• (f) determining, by the controller and using image information captured by the vision system during operation of the actuator in both a first rotational direction and a second rotational direction, a value indicative of mechanical backlash between the actuator and the engine, and automatically adapting the error signal or the actuator control based on the determined backlash value.