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IF paint is applied to a blasted surface in sufficient quantity the wet film will form a plane surface (neglecting variations in thickness due to spray pattern or brush marks) and there will be a greater thickness of paint over hollows than over the peaks. This condition can be accentuated if, in addition, paint flows from peaks to hollows during the drying process. When multi‐coat schemes are applied the surface profile is filled progressively by successive coats of paint (see Fig. 1); if sufficient paint is applied the dry paint/air surface may approximate to a plane. Estimates of paint requirements, albeit approximate ones, can only be properly made on the assumption that this condition will be attained.

This paper aims to present a new trajectory optimization approach targeting spray painting applications that satisfies the paint thickness requirements of complex-free surfaces.

In this paper, a new trajectory generation approach is developed to optimize the transitional segments at the junction of adjacent patches for straight line, convex arc and concave arc combinations based on different angles between normal vectors of patches. In addition, the paint parameters including the paint gun velocity, spray height and the distance between adjacent trajectories have been determined in the generation approach. Then a thickness distribution model is established to simulate the effectiveness of trajectory planning.

The developed approach was applied to a complex-free surface of various curvatures, and the analysis results of the trajectory optimization show that adopting different transitional segment according to the angle between normal vectors can obtain the optimal trajectory. Based on the simulation and experimental validation results, the proposed approach is effective at improving paint thickness uniformity, and the obtained results are consistent with the simulation results, meaning that the simulation model can be used to predict the actual paint performance.

This paper discusses a new trajectory generation approach to decrease the thickness error values to satisfy spray paint requirements. According to the successfully performed simulation and experimental results, the approach is useful and practical in overcoming the challenge of improving the paint thickness quality on complex-free surface.

Automatic trajectory generation for spray painting is highly desirable for today’s automotive manufacturing. Generating paint gun trajectories for free‐form surfaces to satisfy paint thickness requirements is still highly challenging due to the complex geometry of free‐form surfaces. In this paper, a CAD‐guided paint gun trajectory generation system for free‐form surfaces has been developed. The system utilizes the CAD information of a free‐form surface to be painted and a paint gun model to generate a paint gun trajectory to satisfy the paint thickness requirements. A paint thickness verification method is also provided to verify the generated trajectories. The simulation results have shown that the trajectory generation system achieves satisfactory performance. This trajectory generation system can also be applied to generate trajectories for many other CAD‐guided robot trajectory planning applications.

Aims to experimental determination of paint flow rate flux for elliptical paint sprays. Paint flow rate flux distribution is necessary for computer simulation of the spray painting process.

Different painting strokes at different spray distances and painting velocities are made on flat surfaces by using paint sprays with elliptical spray areas. Then, thickness measurements are made across the strokes after the paint dries out completely. Thickness distributions are used for determination of the paint flow rate flux distribution by making use of the developed formulation and algorithm.

Finds that it is possible to determine the paint flow rate flux for elliptical paint sprays by making use of the painting strokes made on flat surfaces at different spray distances and painting velocities.

Computer simulation of the spray painting process for elliptical paint sprays is made possible. Simulation software for circular paint sprays has been developed previously by the authors.

Paint flow rate flux distribution is necessary for computer simulation of the spray painting process. Such simulation software has been developed previously by the authors.

This paper aims to present a new offline robot programming approach for automated trajectory generation on free-form surfaces targeted toward spray painting application.

In this paper, an incremental trajectory generation approach is developed where new paint passes are generated based on paint deposited on the surface as a result of previous paint passes. The trajectory is generated on real surfaces where optimal velocity is calculated using genetic algorithm considering parameters such as surface model, spray gun model, paint distribution model and task constraints.

The developed approach was implemented on various surfaces for different paint distribution patterns, and the simulation results reveal that the approach is flexible and efficient to handle variety in part geometry and paint distribution. From experimental validation and analysis of results thus obtained, the developed approach is highly promising compared to the existing methods.

The approach assumes that the computer-aided design (CAD) model of the surface is available and is limited to surjective surfaces in a structured environment where the spray gun characteristics and process parameters are known beforehand.

The problem of programming a robot manually is overcome by automatically generating a sub-optimal trajectory which can be easily transferred to an industrial robot for spray painting the surface.

This paper discusses a new approach for automated trajectory generation from CAD model. The experimental validation of the developed approach is successfully performed on a highly curved test surface, and obtained results are in agreement with the simulation results.

The purposes of this paper are to review the progress of and conclude the trend for paint thickness simulation for painting robot trajectory planning.

This paper compares the explicit function-based method and computational fluid dynamics (CFD)-based method used for paint thickness simulation. Previous research is considered, and conclusions with the outlook are drawn.

The CFD-based paint deposition simulation is the trend for paint thickness simulation for painting robot trajectory planning. However, the calculation of paint thickness resulting from dynamically painting complex surface remains to be researched, which needs to build an appropriate CFD model, study approaches to dynamic painting simulation and investigate the simulation with continuously changing painting parameters.

This paper illustrates that the CFD-based method is the trend for the paint thickness simulation for painting robot trajectory planning. Current studies have been analyzed, and techniques of CFD modeling have also been summarized, which is vital for future study.

The purpose of this paper is to establish a paint deposition pattern model applied to robotic air spray painting in order to achieve the accuracy and uniformity of paint film thickness on free‐form surface.

The paper opts for an exploratory study using the curvature circle method for air spray painting on free‐form surface to construct a spray gun model. First, a paint deposition pattern model of ellipse dual‐β distribution is fitted on the basic of experimental data from robotic air spray painting. Second, a spray gun model is proposed using the curvature circle method for air spray painting on free‐form surface. The theoretical result is coincident with the film thickness in verification experiment spraying a cylinder surface. The biggest error of the sample points between the theoretical and experimental results is less than 4 μm, thereby the correctness and effectiveness of the proposed model is validated.

The paper provides a specific theoretical and methodological support for the realization of process planning and simulation system in surface spray manufacturing. It will make the future developed system meet the actual processing requirement. At the same time, it is more representative.

The paper finds an approach to solve paint deposition pattern model suitable to free‐form surface. The present method can be applied to the complex reality of topological relation for actual workpiece surface to be painted.

Researchers heavily investigated the use of industrial robots to enhance the quality of spray-painted surfaces. Despite its advantages, automating process is not always economically feasible. The manual process, on the other hand, is cheaper, but its quality is prone to the mental and physical conditions of the worker making it difficult to operate consistently. This research proposes a mathematical cost model that integrates human factors in determining optimal process settings.

Taguchi's robust design is used to investigate the effect of fatigue, stability of worker's hand and speed on paint consumption, surface quality, and processing time. A crossed array experimental design is deployed. Regression analysis is then used to model response variables and formulate cost model, followed by a multi-response optimization.

Results reveal that noise factors have a significant influence on painting quality, time, and cost of the painted surface. As a result, a noise management strategy should be implemented to reduce their impact and obtain better quality and productivity results. The cost model can be used to determine optimal setting for different applications by product and by industry.

Hardly any research considered the influence of human factors. Most focused on robot trajectory and its effect on paint uniformity. In proposed research, both cost and quality are integrated into a single objective. Quality is measured in terms of uniformity, smoothness, and surface defects. The interaction between trajectory and flow rate is investigated here for the first time. A unique approach integrating quality management, statistical analysis, and optimization is used.

The purpose of this paper is to analyze a new structural design applied in industrial frames using two type of steels (S275 and fire resistant (FR)) with different mechanical resistance against fire. To do it, the authors have taken into account variables such as intrinsic metallic design, span length, intumescent paint thickness, and fire time exposure, which offers information about new scenarios of design in industry.

The key methodology followed has taken into account a modeling program that uses the following variables: 25 and 35 m of span, 45 and 60 fire exposure times, and seven different intumescent paint thickness. An optimum structural design has been evaluated by discretization of each scenario with the particular type of steel, S275 and FR. The obtained approach could be a good guideline for future designs.

The results and analysis have shown a very good and valid idea of a new structural typology using optimum intumescent paint thickness into the final design of the industrial frame considering that it has two different types of steel. It is in realty a handicap since usually mechanical engineers employ structural steel without paying attention to this new feature.

Cheaper structural designs could be obtained using the two different types of steel considering the proper positioning into the full building.

The validity of design of two types of steel plus intumescent paint in building construction has been shown, and this study will encourage designers to use it, in particular in buildings with high fire risk.

Aims to introduce a self‐adjusting robotic painting process for automotive fuel containers, capable of predicting the required correction action to avoid further defect production.

Presents the development, testing and on‐site implementation of a robotic thermal machine vision system designed for evaluating coat thickness and coverage attributes. Computer simulation is used to study the effect of the painting robot's program on the film build‐up.

Effective technique for the real‐time detection of anti‐corrosive coat's pinholes and pop‐ups. A systematic study for this paint deposition scheme.

The presented detection system and the simulation program methodology could be further studied and modified for other painting applications.

Provides insights validated with on‐site results and systematic study for the automated or the manual adjustments of the robotic painting parameters.

Introduces a novel application of thermal imaging for evaluating coated surfaces. In addition, a first reported case study of automotive fuel container's painting process. Presents potential application to reduce the defects generation thus, improving quality, and reducing production cost.