To drastically enhance the efficiency of conventional machine tool configurations, a novel multi-spindle configuration is proposed. The key advantage of this configuration is that all spindles can simultaneously machine a single workpiece, whereas in conventional multi-spindle machine tools, each spindle is able to machine only a separate workpiece. To avoid the risk of collision among the spindles during machining operation, parallel linear axes, each of which has a vertical axis and a spindle, are regulated synchronously with a rotary table to follow arbitrarily given 2.5-dimensional tool paths. The command trajectory generation algorithm is presented as well as example numerical simulations. A possible problematic issue with the proposed multi-spindle machine tool configuration is discussed, and a practical solution with a case study simulation is presented.

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