Automated scanning systems for non-destructive inspection of curved cylinder-like workpieces
Systems and methods for high-speed non-destructive inspection of a half- or full-barrel-shaped workpiece, such as a barrel-shaped section of an aircraft fuselage. Such workpieces can be scanned externally using a mobile (e.g., translating) arch gantry system comprising a translatable arch frame disposed outside the fuselage section, a carriage that can travel along a curved track carried by the arch frame, a radially inward-extending telescopic arm having a proximal end fixedly coupled to the carriage, and an NDI sensor unit coupled to a distal end of the telescoping arm. The stiffeners of the fuselage sections can be scanned using a mobile scanner platform disposed inside the fuselage section, which platform comprises a radially outward-extending telescopic arm rotatably coupled to a mobile (e.g., holonomic or linear motion) platform and an NDI sensor unit coupled to a distal end of the telescoping arm. The scan data is matched with position data acquired using any one of a plurality of tracking systems to enable the display of NDI features/flaws on a three-dimensional representation of the workpiece.
1. A system for scanning a substructure of a curved cylinder-like workpiece, which substructure extends along an inner surface of the workpiece, comprising:
a mobile platform comprising a frame;
a first actuator which, when activated, exerts a force urging said mobile platform to move;
a first extendible arm comprising a first member pivotably mounted to said frame of said mobile platform and a second member which is translatable relative to said first member;
a second actuator which, when activated, exerts a force urging said first extendible arm to pivot relative to said frame;
a third actuator which, when activated, exerts a force urging said second member to translate relative to said first member;
a first NDI sensor unit coupled to a distal end of said second member;
an encoder device capable of outputting signals representing incremental movements of said first NDI sensor unit along a substructure; and
a computer system programmed to perform the following operations:
controlling said first, second and third actuators and said first NDI sensor unit;
receiving signals from said encoder device;
converting signals from said encoder device into position data representing a position of said first NDI sensor unit along the substructure;
receiving scan data from said first NDI sensor unit; and
correlating the scan data with the position of said first NDI sensor unit along the substructure.
2. The system as recited in claim 1 , further comprising a tracking system capable of tracking a position of said mobile platform relative to the workpiece.
3. The system as recited in claim 2 , further comprising a tracking system capable of tracking a tilt angle of said extendible arm relative to said mobile platform.
4. The system as recited in claim 3 , wherein said tracking system comprises a plurality of cameras, a first plurality of retro-reflective markers attached to the workpiece, a second plurality of retro-reflective markers attached to said mobile platform, a third plurality of retro-reflective markers attached to said second member of said extendible arm, and a motion capture processor.
5. The system as recited in claim 3 , wherein said tracking system comprises a camera, a laser range finder, a first plurality of optical targets attached to the workpiece, a second plurality of optical targets attached to said mobile platform, and a local positioning system processor.
6. The system as recited in claim 1 , wherein said mobile platform further comprises a plurality of omnidirectional wheels rotatably coupled to said frame.
7. The system as recited in claim 1 , wherein said mobile platform further comprises a plurality of rollers rotatably coupled to said frame, said system further comprising a pair of linear tracks along which said rollers roll.
8. The system as recited in claim 1 , further comprising a second NDI sensor unit coupled to said distal end of said extendible arm, said first and second NDI sensor units being located for concurrent scanning of respective substructures of the workpiece.
9. The system as recited in claim 1 , further comprising a compliant support structure between said first NDI sensor unit and said distal end of said second member.
10. The system as recited in claim 1 , wherein said first NDI sensor unit is an ultrasonic transducer array.
11. The system as recited in claim 1 , further comprising:
a second extendible arm comprising a third member pivotably mounted to said frame of said mobile platform and a fourth member which is translatable relative to said third member;
a fourth actuator which, when activated, exerts a force urging said second extendible arm to pivot relative to said frame;
a fifth actuator which, when activated, exerts a force urging said fourth member to translate relative to said third member; and
a second NDI sensor unit coupled to a distal end of said fourth member.