High-Precision Vision-Guided Automated Electrochemical 3D Printing for Microscale Metal Fabrication

Microscale metal fabrication for microelectronics, sensors, and MEMS devices requires precise automated positioning and shape control, particularly challenging on conductive substrates where non-transparency limits conventional vision-based positioning. This letter presents a high-precision vision-guided automated electrochemical 3D printing system that integrates meniscus-confined electrodeposition (MCED) with real-time visual feedback for accurate microscale metal fabrication in air. The system employs a cantilevered micropipette design to avoid obstructing the top-view field, combined with a vision-guided tracking algorithm using closed-loop feedback control to achieve 1.24 µm positioning accuracy with a relative positioning error of 5.17% on non-transparent conductive substrates. An integrated substrate calibration method based on four-point plane fitting and coordinate transformation compensates for surface irregularities and assembly errors, reducing angular deviations to 3.2%. The self-adjusting voxelated MCED approach utilizes pre-defined trajectories to ensure consistent structural geometry despite environmental variations. Experimental validation demonstrates fabrication of complex microscale structures including intersections, arrays, and controlled electrode interconnections. The integrated vision-guidance, automated calibration, and adaptive deposition control establish this system as an automated solution for refined microscale metal fabrication.