Painting Simulation

Multiphysical simulation of a high rotation atomizer with contact charger to calculate the droplet trajectories, in this example, to the chassis of a Volvo V60.

Fully automated Paint Booth

In many industries, well over half of all components are now painted manually simply because of the number and variety of options. The fully automated paint booth will enable the processing of any object in batch sizes of one.

Self-programming Paint Booth for Batch Size One

Project SelfPaint

The programming of a fully automated painting robot is still very expensive using current painting technology. In the "SelfPaint" project we are creating a new self-programming paint booth in cooperation with Fraunhofer Institute for Manufacturing Engineering and Automation (IPA) and the Fraunhofer-Chalmers Research Centre for Industrial Mathematics (FCC) in Sweden.

 

Aims 

The aim of the Fraunhofer research project is to develop a painting booth within three years (2016-2018) that independently and cost effectively scans, measures, and paints an object.

The fully automated paint booth will be capable of processing customized objects that are 1x1x2 m³ in size. This innovation will be suitable for many industries and applications.

Steps for Optimal Painting

Automated painting is a five-step process:

  1. First, a three-dimensional scan of the component is performed.
  2. Data from this scan forms the basis for a fluid dynamic simulation: Simulation software plots the trajectory of the paint particles and then determines the optimum volume of paint and air needed to achieve the required coating thickness.
  3. The system takes the simulation data to plan the most efficient robot path for the painting process. The optimal painting paths in the processing line are determined using intelligent algorithms and precise fluid dynamic flow simulations. Machine learning methods are used to optimize the path.
  4. The component is painted.
  5. Quality assurance check: Is the required coating thickness achieved?
Schematic representation of the 3D scanning process
© ITWM

Schematic representation: 3D scanning process, in this example for a chair.

"We use terahertz technology for the quality control checks, in other words, a beam of light at a wavelength that lies between microwave and infrared. This enables us to measure wet, colored paint without actually touching it," said Dr. Joachim Jonuscheit, deputy department head at ITWM's Center for Materials Characterization and Testing. He added, "The in-house developed 3D scanning technology identifies the object and allows it to be precisely positioned by the parts carrier in the paint booth." This whole process will soon be automated in everyday painting operations: Robots will scan, paint and check the quality of the paintwork – all without human intervention.

Schematic representation
© ITWM

Schematic representation: Scan data are used as the basis for a fluid dynamic simulation.

Schematic representation
© ITWM

Schematic representation: Painting the component, in this example, a chair.

Schematic representation
© ITWM

Schematic representation: Quality checked via terahertz technology.

Modules

Separate modules in the automated paint booth enable:

  • an optical 3D scan of the object to be painted,
  • computer-aided optimization of the painting process, and
  • a non-contact check of the finished coating thickness.

 

Advantages of the "SelfPaint" Technology

  • Enables automated painting of small lots and even customized work pieces, the so called batch size 1.
  • Achieves up to 20 percent savings in paint and reduces solvent emissions by 20 percent.
  • Consumes 15 percent less energy.
  • The operation is five percent faster than conventional manual painting.
  • Reproducibility of the painting operation: In contrast to a human, a machine or a robot always applies the same amount of paint – and, in the ideal case, this is even automatically documented.
  • The automation of painting processes represents an opportunity to return production operations to Europe and Germany and it even increases job safety in the process.

 

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