Parallel kinematic machines are complete new designs for machine tools and robots. The machines are in all cases non Cartesian and have a highly non linear behaviour. Therefore conventional experiences mostly can not be success fully applied. In order to create a precise and high dynamic machine a machine error model has to be systematically developed to understand the effect of manufacturing and assembly tolerances on the part quality. A key for any precise parallel kinematic machine is calibration while conventional calibration methods can not be applied. It was shown that by using a passive unit or coupling mechanism an auto-calibration method could be introduced. The secondary measuring system was not only applied for the one time calibration process but was furthermore introduced for the online regulation during machining. By activating the direct measuring system control the given mechanical machine stiffness was dramatically improved but also the 3-dimensional path accuracy got very precise. Machining of several parts coming from automotive, aerospace, tool & die and model making industry were executed. The results yield to the conclusion, that PKMs have a higher dynamic than comparable conventional machine tools. An example showed, that productivity can be increased by 100 percent. Since PKMs have a reduced number of units, their costs are also smaller than for conventional machine tools. This leads to lower costs per part.
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