Current; inspection methodology for high-precision inspection of a freeform part relies on its Computer Aided Design (CAD) model for inspection planning. Coordinate transformation or registration from the CAD coordinates to the machine coordinates is necessary to translate the inspection plan from the CAD model to the machine. Registration for high-precision, non-contact sensors is traditionally achieved through a high-precision fixture that is dedicated to part geometry, or through human intervention that is slow and unreliable. This dissertation presents a fixtureless inspection methodology that does not require human intervention.; High-precision, non-contact point sensors require standoff control to ensure that the surface of the part is within the working range of the sensor. A Fixtureless Sensor Standoff Control (FSC) method that does not require information from the CAD model is presented. Sensor position for a measurement is determined from previously acquired measurements. Therefore, FSC does not require prior registration.; Measurements acquired using FSC are used to perform in-process computational registration that is necessary for collision avoidance and view planning. Methods that can he used to determine the number of measurements that yield a unique registration solution require the surface normal, along with the coordinates at each point. An in-process method for surface normal estimation is presented. Surface normals are estimated immediately after the coordinates of all neighboring points are acquired. The method uses quadratic curve fitting through a least squares approach on an anisotropic point distribution to determine the surface normal at each point.; Finally, a method to determine the relation between the speed of measurement system operation and measurement uncertainty is presented. An experimental method for dynamic characterization of non-contact inspection machines is described. The results allow the operator to determine the maximum operating speed and maximum sensor sampling frequency for a desired measurement accuracy.; The methods mentioned above were validated on a 4-axis inspection machine designed to measure turbine blades. Simulated surfaces and a turbine blade were used as test cases for experimentation. The fixtureless methodology for inspection of high-precision freeform parts presented in this dissertation caters to modern manufacturing systems that are capable of producing high-precision parts of varied geometry on single manufacturing line.
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