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This paper aims to present a set of processes for obtaining the global spraying trajectory of a cold spraying robot on a complex surface.

The complex workpiece surfaces in the project are first divided by triangular meshing. Then, the geodesic curve method is applied for local path planning. Finally, the subsurface trajectory combination optimization problem is modeled as a GTSP problem and solved by the ant colony algorithm, where the evaluation scores and the uniform design method are used to determine the optimal parameter combination of the algorithm. A global optimized spraying trajectory is thus obtained.

The simulation results show that the proposed processes can achieve the shortest global spraying trajectory. Moreover, the cold spraying experiment on the IRB4600 six-joint robot verifies that the spraying trajectory obtained by the processes can ensure a uniform coating thickness.

The proposed processes address the issue of different parameter combinations, leading to different results when using the ant colony algorithm. The two methods for obtaining the optimal parameter combinations can solve this problem quickly and effectively, and guarantee that the processes obtain the optimal global spraying trajectory.

Model Maker (MM) is a commercial rapid prototyping (RP) system using tiny jets to deposit thermoplastic materials onto a platform to build physical models and the associated support structures. Also, a cutter is employed to plane off the deposited surface in order to maintain smaller layer thickness and hence, model accuracy. The model’s accuracy is mainly affected by the profile layer thickness. The interior filling does not affect the model accuracy or layer thickness very much, but it significantly affects the building time. Hence, a new interior fast filling of MM using a spraying nozzle is proposed in this paper. The detail design, construction, and evaluation of the new proposed fast interior‐spraying process are presented. The results show that the building time using spaying nozzle is only 15 per cent of the time used by the original process.

Sprayed metal coatings are an alternative means of effectively protecting steel structures and equipment exposed to severe environments where other coatings, such as paint, are unsuitable or provide only temporary protection. Selecting the most suitable material for a given application is a very important step in achieving success. For resistance to corrosive environments, zinc and aluminium are the most successful and widely used coatings, both being anodic to iron and steel. The performance of sprayed metal coatings is a function of the environment, coating thickness, adhesion, density and the type of sealer used. The mechanism of adhesion is mainly mechanical, the bond strength being dependent on the application process chosen and standard of surface preparation. This paper describes the results of research work associated with hot sprayed aluminium applied by combustion flame and electric arc processes using compressed air and argon carrier gases. Studies included ductility and adhesion tests, scanning electron microscopy of surfaces and cross sections, and Auger surface analyses.

Zinc was well established as a protective coating for steel before metal spraying was introduced on a commercial scale, and it was natural that sprayed zinc should be to the fore amongst sprayed metal coatings, a position which it has never lost. During the last 15 years, wide fields of usefulness have been developed for zinc‐sprayed coatings which are often peculiar to them. Today it is rare for a decision to have to be made as to whether or not spraying or galvanizing should be used, the controlling factors in most cases being obvious. The use of zinc‐sprayed coatings on large structures, usually on site, is well known, but there has been comparatively little published information on its many other applications.

Traditional rapid prototyping (RP) uses one nozzle, with a single‐diameter, to conduct spraying of a RP part. The process is usually time‐consuming and inefficient. To improve the traditional method, this research aims to develop a new approach by planning an adaptive path and applying it to the spraying process of every slice. Each accurately sprayed slice then adds one upon another to form a RP part. The processing includes four steps, which will help to produce the adaptive path file, which can be input into the RP machine to make a prototype.

The purpose of this paper is to report salt spray testing of epoxy‐polyester top‐coating applied on Zn‐sprayed, Al‐sprayed and 85Zn‐15Al‐sprayed steel samples.

In these tests, steel substrates sprayed with Zn, Al and 85Zn‐15Al coatings of different average thicknesses ranging from 120 to 210 μm were top‐coated with an epoxy‐polyester sealing layer. The corrosion test was performed with salt solution for over 2,000‐h. The degree of damage to the samples was evaluated quantitatively in terms of ratio of scribed to unscribed area of coating.

It was evident that the corrosion resistance of Al‐sprayed top‐coated surfaces was better than coated Zn‐spray or coated 85Zn‐15Al‐spray systems. As a result, when Al‐coated surfaces were top‐coated with polymeric layer, it was found that their surfaces were remarkably unaffected by the salt spray environment.

The salt spray measurements indicated that the Al‐spray epoxy‐polyester polymer double system was more durable than the other two systems (polymeric top‐coated Zn‐spay, and polymeric top‐coated 85Zn‐15Al‐spray), so far as protection from the chloride salt spray environment was concerned.

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.

Nowadays, food problems are likely to arise because of the increasing global population and decreasing arable land. Therefore, it is necessary to increase the yield of agricultural products. Pesticides can be used to improve agricultural land products. This study aims to make the spraying of cherry trees more effective and efficient with the designed artificial intelligence (AI)-based agricultural unmanned aerial vehicle (UAV).

Two approaches have been adopted for the AI-based detection of cherry trees: In approach 1, YOLOv5, YOLOv7 and YOLOv8 models are trained with 70, 100 and 150 epochs. In Approach 2, a new method is proposed to improve the performance metrics obtained in Approach 1. Gaussian, wavelet transform (WT) and Histogram Equalization (HE) preprocessing techniques were applied to the generated data set in Approach 2. The best-performing models in Approach 1 and Approach 2 were used in the real-time test application with the developed agricultural UAV.

In Approach 1, the best F1 score was 98% in 100 epochs with the YOLOv5s model. In Approach 2, the best F1 score and mAP values were obtained as 98.6% and 98.9% in 150 epochs, with the YOLOv5m model with an improvement of 0.6% in the F1 score. In real-time tests, the AI-based spraying drone system detected and sprayed cherry trees with an accuracy of 66% in Approach 1 and 77% in Approach 2. It was revealed that the use of pesticides could be reduced by 53% and the energy consumption of the spraying system by 47%.

An original data set was created by designing an agricultural drone to detect and spray cherry trees using AI. YOLOv5, YOLOv7 and YOLOv8 models were used to detect and classify cherry trees. The results of the performance metrics of the models are compared. In Approach 2, a method including HE, Gaussian and WT is proposed, and the performance metrics are improved. The effect of the proposed method in a real-time experimental application is thoroughly analyzed.

The purpose of this paper is to study the effect of surface salt spray duration on the fretting wear and electrochemical corrosion behaviors of Inconel 690 alloy.

A high-temperature steam generator was applied to salt spray test samples, a fretting wear rig was used to realize the damage behavior tests, an electrochemical workstation was applied to analysis the changes of each sample’s corrosion dynamic response before and after fretting wear.

The thickness of the oxide film that formed on sample surface was increased with the salt spray duration, and somewhat it could act as lubrication during the fretting wear process; however, the corrosive chloride would accelerate the fretting mechanical damage behavior.

In a salt steam spray condition, the fretting tribo-corrosion behaviors of Inconel 690 alloy surface was studied.

Since the 1950s, Ocean Spray cranberry growers have typically seen themselves in terms of their membership in the Ocean Spray cooperative rather than as cranberry growers. This association with the cooperative is so powerful that both members and independents alike believe that without Ocean Spray, the cranberry industry would not exist as it does today. Yet, as a way to recoup the losses resulting from the recent cranberry glut, some member-growers have proposed selling the cooperative. Although the sale would have generated a large sum of money for them, growers voted overwhelmingly against it. In order to understand why growers identify so closely with the cooperative, this paper intends to demonstrate how Ocean Spray’s influence transcended its role as a marketing cooperative to that of a significant social institution.