Automation and Control of the Electrocatalytic Layers Formation Using a Two-Dimensional Coordinate Spraying Machine

The paper describes the developed automated device for the formation of electrocatalytic layers used in electrochemical systems, and the issues of development of the sputtering technology, which allows to obtain the best parameters of the formed active layers. The general scheme of the automated device includes a system of automatic positioning of the spraying head according to two coordinates, driven by stepper motors controlled by a personal computer, an ultrasonic mini-disperser, a spraying head, ultrasonic generators for the ultrasonic mini-disperser, and the ultrasonic spraying head. Stepper motors were controlled by microprocessor system based on 8-bit Atmel AT90S2313 single-chip microcontroller and standard buffer microcircuits. The key actuating element of the device and the process is the developed atomizing head with an integrated ultrasonic homogenizer that prevents sedimentation of the catalytic composition. The overall automation circuit designed and reproduced to control all electronic devices was described in detail. It differed by application of Attiny2313 microprocessor for the control, availability of communication with personal computer via RS-485 interface that allowed not only to switch the disperser on/off, but also to control its working frequency directly from the personal computer. It was envisaged both manual control of stepper motor controller via control buttons and control from external personal computer, which had the opportunity to control spraying program step by step. In this case all the sequence of steps is contained in the personal computer memory, it is transmitted to the stepper motor controller step-by-step as the program is being executed. Algorithms for moving the spraying head that provide the best drying of catalytic composition in the process of its application have been developed. The effectiveness of the developed automated device has been shown by comparing it with manual application by a specialist according to such criteria as the rate of application of electrocatalytic layers and their quality. The created device, algorithms of its operation, software and scientific and technological advance, in general, can be used for the formation of various coatings both in electrochemical technologies and in other fields.

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