Development of Laboratory Modules for Use in Measurement and Instrumentation, and Applied Quality Control Courses

Equipping engineering students with the skills and knowledge required to be successful global engineers in the 21st century is one of the primary objectives of undergraduate educators. Ideally, a properly trained workforce of engineers and technicians should have expert skills in quality control, measurements and instrumentation to maintain higher productivity, and to improve safety standards in the industry. An expert can detect and/or predict deteriorating cutting conditions through the use of his/her senses so that appropriate corrective actions can be taken before part quality is lost. However, this level of expertise requires many years of experience. Furthermore, machine tools should be brought to a thermally stable state by running at idle mode for several hours so that positional errors can be minimized. This requirement increases machine down time and production costs. Machine tools have inherent geometric errors caused by mechanical imperfections in their structure, and misalignment of machine tool elements. Geometric errors are also affected by the thermal state of the machine tool structure. Hence process and structural factors affecting part accuracy in machining processes are quite complicated. CNC machine tools only minimizes a small portion of these errors since CNC often does not utilize sensor data to compensate for geometric-thermal errors and errors generated by the cutting process. Therefore, we must provide our students, through our curriculum, with an adequate level of expertise through new programs, courses and support laboratories. This paper is focused on description of new laboratory modules, teaching materials, practical experiments and projects developed as an integrated educational environment similar to ones used in the present day industry. The projects and practical activities are developed and implemented around Renishaw Magnetic Double Ballbar (DBB), HAAS OM1A 3-Axis CNC Vertical Machining Center and Coordinate Measuring Machine (CMM). Course materials and laboratory manuals are also developed, upgraded and restructured during this project. The educational material is implemented as course improvements in undergraduate and graduate courses such as Measurement and Instrumentation, Applied Quality Control, Engineering Quality Methods (graduate) and Sensors and Measurements (graduate). The experimental activities are focused on several aspects applicable in manufacturing industry concerning measurement, instrumentation and quality control. One area where we concentrated our efforts is the calibration technology of a CNC using machined parts and a CMM. This approach yields valuable information on non-repeatable errors due to cutting forces, heat generated by cutting, tool setup, wear, and deflection. CMM is used also as a post process confirmation of the machined test components and other discrete parts machined in the HAASOM1 Vertical Machining Center. Then the deviation between the real part and the theoretical part is measured. Another area of focus is related to characterization of the factors and error components that contribute to machine tool errors using a DBB.