In Situ Optical CT Monitoring for Volumetric 3D Printing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Volumetric additive manufacturing systems operate in an open loop fashion, struggling to accurately handle nonlinear optical responses and material property variations during the curing process, resulting in errors and reduced precision in the final geometry of printed parts.
Innovation Solution
Incorporating an in situ cure monitoring control system that uses optical Computed Tomographic (CT) images to generate real-time feedback on the curing state of the resist, allowing for adjustments to the curing beam to optimize the curing process.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If open loop volumetric AM printing is used, then the printing speed and productivity are improved, but the manufacturing precision and quality of final parts deteriorate due to inability to account for errors in real time
Solution Approach 1:
The patent implements a closed-loop control system that uses optical CT scanning to monitor the cure state of resist in real time during volumetric printing. The system captures 3D images of the curing process, compares the actual cure state against the desired cure map, and uses feedback to dynamically adjust printing parameters. This feedback mechanism resolves the contradiction by enabling real-time error correction while maintaining high printing speed, thus improving manufacturing precision without sacrificing productivity.
2Manufacturing precision
If real-time feedback monitoring is implemented, then the manufacturing precision and quality are improved, but the device complexity increases due to additional sensing and control systems
Solution Approach 1:
The patent employs an optical CT scanning system that serves multiple functions: it monitors the cure state of resist, captures 3D structural information, and provides feedback for control adjustments. By using a multi-functional sensing system, the patent reduces overall device complexity while achieving high manufacturing precision through real-time monitoring.
3Measurement precision
If optical CT scanning is used for real-time monitoring, then the measurement precision of cure state is improved, but the loss of time for scanning and processing images increases
Solution Approach 1:
The system performs preliminary actions by pre-planning the scanning paths and processing sequences before actual monitoring begins. The optical CT scanner is configured with pre-programmed scanning patterns that optimize image acquisition speed, and the processing system prepares analysis algorithms in advance. This preliminary preparation reduces the time penalty associated with high-precision measurement during the actual curing process.
4Reliability
If closed-loop control with real-time modification is implemented, then the reliability and determinism of the curing process are improved, but the device complexity and difficulty of operation increase
Solution Approach 1:
The closed-loop control system operates autonomously by automatically comparing measured cure states against target specifications and adjusting printing parameters without manual intervention. The system self-corrects errors in real time, improving reliability and determinism while maintaining ease of operation through automation. The intelligent control algorithm handles the complexity internally, presenting a simple interface to the operator.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach significantly improves the precision, quality, and determinism of the 3D printing process by enabling real-time modification of the curing map, leading to better resolution and repeatability in the final parts produced.
Implementation Method 1
an optical signal source configured to generate optical signals having a wavelength selected in relation to a characteristic of the resist, and directed to pass through the build volume as the curing beam is also passing through the resist. A detector may be included which detects the optical signals after the optical signals have passed through the resist
Data Source
AI summary
An in situ cure monitoring control system for use with a volumetric three dimensional (3D) printing system, wherein the volumetric 3D system includes a container defining a build volume, the container includes a photocurable resist used for making a 3D part, and the resist is responsive to an optical curing beam from a light source, which is controlled by a controller, and which is passed through the resist. The cure monitoring control system includes an optical signal source which generates optical signals having a wavelength selected in relation to a characteristic of the resist, and directed to pass through the build volume. A detector detects the optical signals and generates output signals in accordance therewith. Software monitors the output signals and uses the output signals to modify the curing beam to help optimize curing of the resist.