The first part of the master's thesis presents the optimization of the existing machine, which is intended for depositing cast stators on a pallet laying on a conveyor belt, after which they are taken for machine inspection. The stators are stacked on trays, which are loaded onto carts, and then together loaded into machine. The storage servomotors lift the tray to the transmission by means of grippers, which is moved by an additional servomotor. The robot picks up each stator separately, takes it to the location of the QR code reading, then to check the hue of its color, and finally to the palette located on the conveyor belt. First, some mechanical modifications that were necessary for more reliable operation of the machine are presented. The program is described with the following: production of a program block for moving servomotors, production of a fully automatic cycle of storage and transmission, optimization of manual machine mode, code for performing measurement capture in color sensor measurement system analysis and screen control panel optimization. Programming took place on a Siemens system using their TIA Portal programming environment.
The machine also includes measurements of the color shades of the stators, with the help of which the verification of their heat treatment is performed. Therefore, in the second part of the master's thesis, the analysis of measuring systems is presented, which we must perform on our sensor. Measuring systems must ensure that excessive deviations from the real value do not occur when performing measurements. The analysis of the measuring system checks the stability, which represents the change of bias over time, bias, which represents the difference between the reference value and the average of some measurements, linearity, which shows the bias difference throughout the measuring range of the system, repeatability, which represents the difference between successive measurements of one appraiser and reproducibility, which represents the difference between the average measurements of individual appraisers. Repeatability and reproducibility can be considered together to obtain a variance equal to the sum of the variations within the measurement system. The measuring system meets our requirements when all the listed properties are within the limit values.
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