This paper presents a comparative analysis of bearing and rotating component fault classification based on different time–frequency representations using vision transformer (ViT). Four different time–frequency transformation techniques—short-time Fourier transform (STFT), continuous wavelet transform (CWT), Hilbert–Huang transform (HHT), and Wigner–Ville distribution (WVD)—were applied to convert the signals into 2D images. A pretrained ViT-Base architecture was fine-tuned on the resulting images for classification tasks. The model was evaluated on two separate scenarios: (i) eight-class rotating component fault classification and (ii) four-class bearing fault classification. Importantly, in each task, the samples were collected under varying conditions of the other component (i.e., different rotating conditions in bearing classification and vice versa). This design allowed for an independent assessment of the model’s ability to generalize across fault domains. The experimental results demonstrate that the ViT-based approach achieves high classification performance across various time–frequency representations, highlighting its potential for mechanical fault diagnosis in rotating machinery. Notably, the model achieved higher accuracy in bearing fault classification compared to rotating component faults, suggesting higher sensitivity to bearing-related anomalies.

This paper deals with some problems in the modernization of a type of machine tools with multi–coordinate drive systems. The basic requirements to the drives of each coordinate axis and the spindle are presented. Using the analysis carried out, a practical approach to appropriate selection of the respective drives is applied. The methodology offered is illustrated with some examples for choice of drives with direct current and alternating current motors. Some experimental research of cases with different feed and spindle drives are described and discussed. Better capabilities of the modernized machines for processing more complex workpieces are achieved, at a relatively low price. This research and the obtained results can be used in the design and tuning of electric drives for the considered type of machines with numerical program control.

The basic features of the auxiliary drives in a kind of machine tools are analyzed in the presented work. Based on this, a control algorithm of the additionally introduced auxiliary drive has been developed taking into account the mechanical gear, the type of the computer numerical control and the respective sensors. Two different approaches for control of this drive are shown, namely one with ladder diagrams and one with the Verilog hardware description language (Verilog HDL). Experimental results of the implemented control device with Verilog HDL are presented and discussed. The research carried out and the results obtained can be applied in the design of such drives for the machine tools under consideration.

An approach to dual-zone speed control of DC motor electric drives is presented in this paper. The new point is that in the syntheses of controllers a combination between setting of closed-loop system poles (modal control) and optimal control through the quadratic quality criterion minimization is applied. Optimal modal control is achieved whereat a new type of complex criterion for selection of the functional is used. This approach allows taking into consideration the controlled object parameters' change at determination of the optimal modal controller coefficients when speed is regulated above the rated value. The research carried out as well as the results obtained can be used in the design, optimization and tuning of such types of drive systems

The main features of the tool magazine drive in a type of vertical machining centers with computer numerical control are analyzed. On this basis, an algorithm for optimal tool position searching has been presented. A control device using Verilog hardware description language has been developed. The approach offered achieves autonomous control of this drive and reduces the requirements to the respective CNC system. Experimental results of the synthesized control device and practical applications of the implemented tool magazine drive are presented and discussed. This research and the results obtained can be used in modernization of the considered machine tools.

The possibilities for reducing the energy consumption in CNC turning machines are formulated and analyzed in this paper. On this basis, some measures for energy efficiency improvement are offered. Experimental results from the research carried out are presented and discussed. This study and the results obtained can be used in the modernization and practical application of the considered class of machine tools.