Fabrication of conformal ultrasound transducer arrays and horns based on multi-axis CNC accumulation

Ultrasonic imaging is an important medical imaging technique. It uses ultrasound over 20K Hz to detect and visualize muscles, tendons, and many internal organs. Previous studies have shown that an improved acoustic performance can be achieved by conformal ultrasound transducer arrays and horns that can wrap conformably around curved surfaces. To address challenges in fabricating such curved ultrasound transducer arrays and horns, we investigate the possibility of using a newly developed additive manufacturing (AM) process named CNC accumulation. In such an AM process, an accumulation tool can have multi-axis motion, which is beneficial for building conformal ultrasound transducer arrays and horns on a curved surface. To address different resolution requirements, we illustrate the use of multiple accumulation tools that can have different curing sizes and power in the fabrication of a single component. The tool path planning methods for any given cylindrical and spherical surfaces have been discussed. Based on the developed prototype system, various test cases have been performed. The experimental results have illustrated the capability of the process and its potential use in the fabrication of conformal ultrasound transducer arrays and horns. The current limitations and future development have also been discussed.