This paper presents an analysis of the geometric errors of joint assembly that affect the end-effector for a six-axis industrial robot. The errors were composed of 30 parameters that come from the Geometric Dimensioning and Tolerancing (GD&T) design, which is not the normal way to describe them. Three types of manufacturing tolerancing—perpendicularity, parallelism and position—were introduced and investigated. These errors were measured by the laser tracker. The measurement data were calculated with an analysis of the circle fitting method. The kinematic model and error model based on a combination of translations methods were used. The experiment was carried out in order to calculate the tolerancing of geometric error. Then, the positions of the end-effector in the actual measurement from laser tracker and exact performance were compared. The discrepancy was compensated by offline programming. As a result, the position errors were reduced by 90%.

In general, rubber parts used in automotive applications are designed and manufactured without any inserts; it is significant, however, that for certain parts, such as an engine mounting that, the metal core must be used to increase the compressive strength of products. With the lack of numerical tools used to predict the rubber flow characteristics and the interaction between rubber and metal insert during the molding process, mold designers must rely on their experience and the trial-and-error method to design molds. Therefore, in this research, an application of CAD/CAM/CAE on the design and manufacturing of an injection mold for the engine mounting rubber made of a blend of Natural Rubber (NR) and AcryloNitrile-Butadiene Rubber (NBR) is performed. A CAD model of the part is constructed and then a two-cavity mold as well as various runner patterns and gate positions are designed and further analyzed using CAE. Subsequently, with use of the CAM system, a metal-inserted mold and related components are manufactured and used to produce the rubber engine mounts on the vertical rubber injection machine. The empirical and numerical resulting parameters, including part geometry, injection pressure, and part temperature at various injection stages, correlate well. This information provides mold designers and manufacturers a better understanding of the rubber behavior during curing in the metal-inserted rubber molding process so that various mold components can properly designed and effectively used. Consequently, better mold and product quality with less defects as well as reduced production time can be obtained.

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Asian Syrnposium on Materials and Processing 2006 (1{SMP 200ov iVovember 9-70, 2006, Bangkok, T7?aitand Application of Reverse Engineering for lmproved Rubber Mould Inspection System 1,2. ri ri,3 a,3