An apparatus for detecting the probable existence, location, and type of defects in a workpiece is described. The apparatus includes a sensor subsystem, an optimizer, a control subsystem, and a computer system having a processor and computer readable memory. Sensor subsystem senses a first section of the workpiece and produces signals corresponding to a physical characteristic of the workpiece. The computer system is configured to generate a workpiece model based on the signals produced by the sensor subsystem. In an alternate embodiment, a defect assembler can be provided to merge signals from a plurality of sensor subsystems. The defect assembler can also be configured to generate the workpiece data model. The optimizer is configured to generate workpiece segmentation recommendations based on the workpiece data model. The processor is configured with a first producer thread program which, in response to the receipt of a first set of signals by the computer system, receives a data subscription request from a subsystem which uses data and transmits the signals from the computer readable memory to the generator of the data subscription request. The processor is further configured to generate a second producer thread in response to storage of a second set of signals in the computer readable memory. The second producer thread is configured to receive one of the data subscription requests and selectively send the second set of signals to the generator of the data subscription request. A tracking device for tracking selective kinematics of a workpiece moving through a plant is also disclosed. The tracking device includes an encoder wheel configured to tangentially contact a workpiece and rotate at an angular velocity coincident with the linear velocity of the workpiece. The tracking apparatus further includes a drive mechanism for driving the encoder wheel at a first angular velocity approaching the angular velocity of the encoder wheel which is coincident with the linear velocity of the workpiece. The tracking device also includes a signal generator configured to interact with the encoder wheel and generate a signal in response to the angular velocity of the encoder wheel. The tracking apparatus can be incorporated into the apparatus for detecting defects within a workpiece by providing the signal from the signal generator to the control subsystem.