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This paper presents strategies for active error compensation in contour controlled grinding of forged crankshafts. The discussed approaches could also be applied to camshafts and similar long, compliant workpieces. For compensation of distortions and unequal allowance distributions an active tailstock is introduced. A hybrid principle combining hydraulic and piezoelectric actuation is analyzed. The dynamics and precision of the piezoelectric actuator can be used to improve the response behavior whereas the hydraulic actuator possesses the necessary strokes. The actuation principle will be integrated into an active 2-DOF tailstock and combined with optical geometric measurement devices. Different influences on the grinding process are discussed and a model based pre-control strategy is presented which considers process forces, machine and workpiece compliance, coolant influence, and machine control behavior. Measurements show, that an accuracy improvement and a reduction of spark out time can be achieved. Further investigations will lead to even more accurate models and a higher performance of the strategy.