The modelling and compensation method for dove-prism-based laser trepanning optomechanical system

Laser beam drilling is widely employed in the aerospace industry due to its non-contact nature and efficient processing of various materials. While traditional fixed laser beam drilling methods such as Single Pulse Drilling (SPD) and Percussion Laser Drilling (PLD) are commonly used, mobile laser beam drilling techniques like Laser Trepanning and Helical Drilling are preferred for applications requiring precise control over hole geometric accuracy. This paper presents a new Dove-prism-based trepanning system model that enables analytical calculation of the laser trajectory within a 3D spiral domain. This model facilitates accurate prediction of drilled hole geometries, including diameter and taper. An innovative aspect of this study lies in the incorporation of a laser ablation effect into the prediction of hole geometry, which is often overlooked in other trepanning drilling research. By integrating a prediction function for ablation crater diameter, the accuracy of hole geometry prediction can be improved. The validity of the model is confirmed through extensive experiments, establishing its reliability while revealing important insights such as the impact of initial optomechanical conditions on hole geometry and the influence of laser parameters on hole circularity. Additionally, our compensation method enhances predictability and expands achievable geometry range when drilling holes. This research establishes a robust theoretical foundation for advancing mobile laser drilling technology, particularly in terms of system design and process optimization.