Additive Manufacturing Recoater Torque Monitoring

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current additive manufacturing systems lack automatic detection of defects such as part swell and incomplete recoats, which can lead to damage or inefficiencies in the powder bed fusion process, with no effective monitoring system for recoat quality or coverage.

Innovation Solution

A method that utilizes torque data from a powder recoater to determine the quality of the additive manufacturing process and product by comparing it with reference data, alerting users to incomplete recoats or part swell, and optionally adjusting the recoat or laser power based on the analysis.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional additive manufacturing systems are used without torque monitoring, then the system structure remains simple, but defect detection capability is poor leading to undetected part swell and incomplete recoats

Engineering Contradiction:
Improvedefect detection capabilityVSAvoidsystem complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent replaces complex optical or sensor-based monitoring systems with a simple torque measurement system. By measuring the torque required to rotate the recoater roller, the system infers defects like part swell and incomplete recoats without requiring additional complex mechanical or optical components. This substitution achieves high measurement precision while maintaining relatively simple device architecture.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent introduces torque data as an intermediary parameter that indirectly indicates defect conditions. Instead of directly detecting defects with complex sensors, the system uses torque measurements as a mediator to infer the presence of part swell, incomplete recoats, or other anomalies. This intermediary approach enables defect detection while avoiding the complexity of direct detection systems.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If real-time torque monitoring is implemented, then defect detection accuracy improves, but the system complexity and cost increase

Engineering Contradiction:
Improveprocess monitoring reliabilityVSAvoidmonitoring system complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent makes the existing recoater motor serve a dual function: both performing the recoating operation and providing torque data for defect detection. By utilizing the inherent torque measurements already generated during normal recoating operations, the system achieves reliable process monitoring without adding separate monitoring motors or sensors. This self-service approach increases reliability while minimizing additional system complexity.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent implements a feedback mechanism where torque measurements are continuously monitored and compared against expected ranges to detect anomalies. The system provides real-time feedback about recoating quality and part conditions, enabling immediate detection of issues like part swell or incomplete coverage. This feedback loop enhances reliability by ensuring continuous monitoring while using simple computational logic rather than complex control systems.

Inventive Principle:
Principle #23Feedback

3Manufacturing precision

If torque data is used to detect incomplete recoats, then recoat quality improves, but the system requires new measurement capabilities

Engineering Contradiction:
Improverecoat qualityVSAvoidmeasurement system complexity
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The patent replaces complex optical or capacitive sensors for measuring recoat quality with simple torque measurements on the recoater roller. By substituting mechanical torque sensing for optical measurement systems, the patent achieves high manufacturing precision for recoat detection while avoiding the complexity and cost of optical measurement infrastructure.

Inventive Principle:
Principle #28Mechanics substitution (Replace mechanical system)

Solution Approach 2:

The patent makes the recoater torque measurement system multi-functional, using the same torque data to detect multiple defect types including incomplete recoats, part swell, and potential crashes. This universal approach to quality control improves recoat quality monitoring while avoiding the need for separate specialized sensors for each defect type, thereby reducing overall system complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

4Productivity

If automatic defect detection is implemented, then productivity is improved by preventing crashes, but the system complexity increases

Engineering Contradiction:
Improvemanufacturing efficiencyVSAvoidcontrol system complexity
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent enables the recoater system to self-monitor its own operational status through torque measurements. By using the inherent torque data from the recoating process to detect potential crashes or defects, the system improves productivity through automatic protection without requiring a separate complex monitoring and control system. The recoater essentially monitors itself, achieving high productivity with minimal additional complexity.

Inventive Principle:
Principle #25Self-service

Solution Approach 2:

The patent implements simple feedback logic that monitors torque measurements and triggers alerts or process adjustments when anomalies are detected. This feedback mechanism prevents crashes and defective builds, improving manufacturing efficiency by reducing waste and rework. The feedback system uses straightforward threshold-based detection rather than complex predictive algorithms, maintaining low system complexity while achieving high productivity benefits.

Inventive Principle:
Principle #23Feedback

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

Enables real-time monitoring and improved quality control by detecting incomplete recoats and part swell, preventing damage and ensuring consistent layer thickness, thereby enhancing the overall additive manufacturing process efficiency and product quality.

Implementation Method 1

a torque sensor positioned on the roller that rotates relative to the powder bed to detect a torque applied to the roller during the recoating process

Methodology Applied
Scientific EffectTorque measurement: Torque

Data Source

PatentEP3168035B1Additive manufacturing quality control systems
Publication Date: 2019.11.13 HAMILTON SUNDSTRAND CORP
  • EP3168035B1 patent drawingFigure 1~2
  • EP3168035B1 patent drawingFigure 3~4

AI summary

A method 100 includes receiving 101 torque data of a powder recoater (201) operatively connected to an additive manufacturing system (200). The torque data includes torque data of the recoater (201) when the recoater traverses a build area (205). The method also includes determining 103 a quality of one or more of an additive manufacturing process and/or product based on the torque data.