The application discloses a three-freedom-degree large-
stroke fast-tool-
servo device, which comprises a
workbench, a
voice coil motor, a Z-direction displacement transmission mechanism, a three-axis connecting mechanism, an X-direction driving platform, a Y-direction driving platform, a
tool holder and a tool. The three-axis connecting mechanism comprises a three-axis connecting plate and a three-axis connecting frame, and the three-axis connecting plate is connected with the three-axis connecting frame through X-axis and Y-axis flexible hinges around the three-axis connecting plate. The flexible hinges are provided with Z-axis flexible hinge points. The double-axis flexible hinges are provided with at least one X-axis flexible
hinge point and one Y-axis flexible
hinge point. The Z-direction displacement transmission mechanism, the three-axis connecting mechanism and the driver connecting rod are designed in an integrated mode. The piezoelectric
ceramic driver is adopted. The three-freedom-degree active
cutting of the tool can be realized, the large-
stroke output capacity is achieved, the
machining process of a complex
optical surface can be efficiently completed, the displacement errors in multiple directions can be compensated, and the
cutting force disturbance problem is solved.