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This paper presents an in-process inspection-oriented autonomously generative CMM (Coordinate Measuring Machine) part programming methodology with a simplified part programming process to decrease the time and skill for CMM part programming. The proposed method differs from the CAD-based CMM programming approach. Using this new method, machining features in a complex part can be efficiently inspected after any stage of machining operations or after machining these features. The concept of the proposed CMM part programming approach and its implementation are described in this paper. The results obtained from the feasibility study show the developed CMM part programming system can autonomously generate an inspection plan for a work-in-progress part model generated from NC programs to realize the in-process measurement. [DOI: 10.1115/1.1536175]

Reverse ballistic impact test, which can obtain the response data of rod/projectile more comprehensive and quantitative than forward impact test, was widely used for the measurement of material dynamic and structure response. Based on the DIC technology and traditional optical measurement (high-speed camera measurement), the Taylor experiment of reverse ballistic with different length-diameter ratio and different impact velocities were carried out by 57 mm compression-shear type light-gas gun, which provides the instantaneous response data of the Taylor rod in microsecond level. Then, the transient structural deformation of the specimen and the characteristics of plastic wave propagation were analysed by DIC technology and compared with traditional optical measurement. Applying the theory of reverse Taylor impact deformation and combining with the simulation results by LS-DYNA, the rules of structure deformation and plastic wave propagation were obtained. The method above can be applied for the structure response of penetrator under the condition of reverse ballistic penetration.

In order to increase the accurate finishing productivity of pearlitic cast iron, face milling by CBN (Cubic Boron Nitride) cutting tools was studied. The main focus of the study is the machinability investigation of pearlitic cast iron with CBN cutting tools by studying the relationships among machining conditions such as feed rate, cutting speed as well as CBN cutting tool type, tool wear, workpiece surface quality, cutting forces, and cutting temperature. In addition, an emphasis is put on the effect of Al additive in pearlitic cast iron on its machinability and tool wear characteristics. High-speed milling experiments with CBN cutting tools were conducted on a vertical machining center under different machining conditions. The results obtained provide a useful understanding of milling performance by CBN cutting tools.

The paper deals with the development of a fiber optic sensor for surface roughness measurement. A new method for the calculation of reflection light intensity is proposed. By numerically counting the amount of reflection light rays from a measured surface, the relationship between the reflection light intensity and the surface roughness can be found. The simulation method is useful in understanding the effects of the sensor probe structure and the component parameters on the performance of the sensor such that an optimum sensor design can be obtained. A fiber optic sensor probe for surface roughness measurement was designed and fabricated using the results obtained by simulation. Experimental results show that the prototype sensor probe has high resolution and sensitivity for ground and milled surfaces with the roughness value (Ra) of 0.1 [micro]m~3.2 [micro]m. The experimental results also show that the simulation method is accurate, and hence useful in designing fiber optic sensors. The simulation procedure and feasibility of the simulation method as well as the experimental results obtained from the prototype sensor probe are presented in this paper. [DOI: 10.1115/1.1475991]