Compensation machining of freeform based on fast tool servo system

Area of Science:

• Optical engineering
• Precision manufacturing

Background:

• Freeform optical systems offer advantages like a large field of view but face machining challenges.
• Current methods struggle to meet the stringent optical use requirements for freeform surfaces.

Purpose of the Study:

• To propose and validate an error compensation turning method for freeform surfaces.
• To enhance the machining accuracy of freeform optical components.

Main Methods:

• Utilizing a developed fast servo tool (FTS) device.
• Employing Zernike polynomial fitting for freeform surface error reconstruction from off-line measurements.
• Implementing offset compensation to correct the tool path.
• Building a physical system to simulate and verify the compensation process.

Main Results:

• The developed error compensation turning method was successfully applied to a convex freeform aluminum mirror.
• The surface accuracy of the machined workpiece met visible band requirements.
• The feasibility of the compensation processing was verified through simulation and physical testing.

Conclusions:

• The proposed error compensation turning method effectively addresses machining inaccuracies in freeform optics.
• This research holds significant practical importance for fast-response machining of free-form surface mirrors.
• The method ensures that freeform optical components achieve the necessary surface accuracy for applications like space exploration.