Die Head Position Control for Undulated Substrate Coating

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing coating methods face challenges in accurately following the shape of substrates with undulations due to differences in control response delays between mechanisms for moving the die head parallel and perpendicular to the substrate, especially when the substrate has a large gradient or high moving speed.

Innovation Solution

A control system and program that integrates a measurement sensor with the die head, using model predictive control to adjust the position of the die head along both axes based on real-time measurements, ensuring accurate tracking of the substrate's surface by generating operation amounts for drive devices to maintain a constant distance and follow the target trajectory.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If two mechanisms are linked to move the die head parallel and perpendicular to the substrate simultaneously, then the die head can follow the substrate surface shape, but control response delay differences between the two mechanisms cause positioning errors

Engineering Contradiction:

Improvepositioning accuracy of die headVSAvoidcontrol response delay

Core Design Contradiction:

Manufacturing precisionVSLoss of time

Solution Approach 1:

The control response delay of each mechanism is measured in advance, and compensation values are calculated and stored before actual coating operation. During operation, these pre-calculated compensation values are applied to correct the command positions, eliminating the need for real-time delay correction and ensuring accurate positioning despite different mechanism response times.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

A feedback mechanism is implemented where the actual positions of the die head in both parallel and perpendicular directions are continuously monitored. The measured positions are compared with command positions, and compensation is applied based on the detected deviations and pre-measured response delays, creating a closed-loop control system that corrects positioning errors.

Inventive Principle:

Principle #23Feedback

2Productivity

If the die head moves at high speed to increase productivity, then coating efficiency improves, but the control object becomes unable to accurately follow the substrate surface shape

Engineering Contradiction:

Improvecoating speedVSAvoidsurface shape following accuracy

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

Response delay compensation values are pre-calculated and stored for different operating speeds. Before high-speed coating operation begins, the appropriate compensation values corresponding to the intended speed are loaded into the control system. This allows the system to maintain positioning accuracy even at high speeds by applying the correct compensation in advance.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The control system dynamically adjusts operation parameters including speed-dependent compensation values. When operating speed changes, the system selects or calculates appropriate compensation parameters and applies them to maintain accurate following of the substrate surface shape despite the increased speed.

Inventive Principle:

Principle #35Parameter changes

3Adaptability or versatility

If the substrate has large gradient undulations to coat complex surfaces, then versatility improves, but the control object becomes unable to accurately follow the surface shape due to amplified control delays

Engineering Contradiction:

Improveability to coat undulated surfacesVSAvoidtrajectory accuracy

Core Design Contradiction:

Adaptability or versatilityVSManufacturing precision

Solution Approach 1:

The feedback mechanism continuously monitors the actual die head position and compares it with the command position along the target trajectory. When coating surfaces with large gradients, the system detects positioning deviations caused by amplified control delays and applies real-time compensation based on pre-measured delay characteristics, maintaining accurate following of complex surface shapes.

Inventive Principle:

Principle #23Feedback

Solution Approach 2:

For complex undulated surfaces with large gradients, the control system pre-calculates compensation values based on the measured surface geometry and pre-characterized response delays. This preliminary compensation preparation enables the system to handle steep gradients accurately by anticipating and correcting for delays before they cause significant positioning errors.

Inventive Principle:

Principle #10Preliminary action

Data Source

PatentUS11630426B2Control system and non-transitory computer readable recording medium

Publication Date: 2023.04.18 OMRON CORP

AI summary

A measurement sensor is integrated with a control object so that a position separated from a processing object by the control object along a target trajectory is a measurement point. A control device includes: a first generator that generates a first command position of the control object on a plane; a first control part that generates a first operation amount using a model predictive control; a second generator that generates a second command position of the control object on an orthogonal axis that is orthogonal to the plane; and a second control part that generates a second operation amount using the model predictive control. The second generator generates the second command position so that the distance between the control object and the surface of an object is constant, based on the measurement result of the measurement sensor and the first command position.