Electric wheelchairs make it easier for disabled and elderly people to live, move, interact, and participate in society. Moving a wheelchair in open spaces is relatively easy, but in closed and small spaces, maneuvering is difficult. Solutions to such problems for people with disabilities are applicable to a relatively small group of recipients and are mostly custom-made solutions, whose considerable cost is a significant barrier to accessibility. New technologies can provide an opportunity to improve the quality of life of people with disabilities in this aspect. Using selected elements of complex automation and control systems, cost-effective solutions can be created that facilitate the functioning of people with disabilities. This paper presents an analysis of hazards and problems when maneuvering a wheelchair in narrow passageways, as well as the authors’ solution to this problem, and the concept and assumptions of a mechatronic anti-collision system based on 2D LiDAR laser scanners. This solution is composed of a proprietary 2D rotating scanner mechanism that ensures the acquisition of 3D images of the environment around the wheelchair. Preliminary tests of this solution yielded promising results. Further research will include miniaturization of the device.

The paper presents the process of preparing gear models with an original profile for numerical analyses. We used solid modeling reflecting the gear cutting using the enveloping generation method. A script was prepared in AutoCAD to enable automatic simulation of the material removal process and obtain precise gear models. The analyzed gears had geometry based on Novikov’s engagement; however, during the tool design, the tooth profile was adjusted due to the incorrect values of certain parameters present in the standards. Gears models with a circular-arc tooth profile created in this process were used for finite element method (FEM) calculations in ANSYS. An analysis of the contact pattern for the loaded gearbox was conducted. The stress state for the analyzed gear transmission with the adjusted tooth profile was also determined.

The contact pattern between gear teeth is one of the most significant indicators of proper gear operation. This paper presents an analysis of the contact pattern of gears with a sinusoidal profile. The gear geometry was obtained through direct solid simulation of the machining process. Generally, analytical, numerical, and experimental methods are used for contact pattern analysis in gearboxes. This article presents contact pattern investigations using numerical methods and a novel experimental method that utilizes pressure measurement films. A proprietary program using image analysis was used for the contact pattern analysis. The numerical studies utilized the Finite Element Method (FEM) and the CAD method. The results obtained from the presented methods show good convergence.

This paper presents a strength analysis of helical gears for several selected tooth profiles. Four analogous gear design solutions with identical geometry and functional features were compared, with differences limited solely to the parameters of the gear rim. The primary focus of the research was on gears featuring convex–concave profiles based on Novikov and sinusoidal tooth profiles, which were compared against the standard involute profile. Solid models of the investigated gears were prepared using a CAD (Computer-Aided Design) method developed by the authors. The modelling process, which replicates the generating gear cutting method, allowed for highly accurate gear models to be obtained. The computational models of circular-arc tooth profile gears prepared in this manner were subsequently used for numerical FEM (Finite Element Method) analyses in ANSYS 2025 R2 software. As part of the numerical computations, instantaneous contact patterns and total contact patterns for the loaded gear drive were determined. Furthermore, the stress state at the tooth root and the surface stresses on the contacting tooth flanks were specified. Stress plots in these critical areas, which are essential for gear strength, were generated alongside distribution maps of regions prone to failure. Finally, an evaluation and comparative analysis of the results obtained for all considered gear models were conducted. The conclusions derived from the study provide insights into the stress distribution within critical regions of gears with different circular-arc tooth profiles.

The paper discusses the issue of transverse natural vibrations of toothed wheels intended for operation in aviation power transmission systems or in the transmission of aircraft engine aggregates. The discussion was conducted using wheels with straight, oblique and circular-arc teeth, as well as with a full wheel disc and a wheel disc with eccentric holes. In the analysis process, simplified toothed ring models were proposed for each gear in the form of rings made of a hypothetical material with satisfactory physical properties (equivalent values of Young’s modulus and the density). In the proposed models were also taken into account the properties of cyclic symmetry exhibited by the studied objects. The calculation process was carried out using the finite element method and the commercial ANSYS software. The influence of the type and size of finite element on the quality of the obtained results was also investigated. The main part of the work concerns the assessment of the usefulness of the proposed simplified models of the analyzed wheels in the vibration simulation process. In order to confirm the correctness of the simulation research methodology, for one of the analyzed wheel cases, the numerical simulation results were verified experimentally on a real object. The article concludes with remarks and conclusions regarding the obtained results. The issues presented in this paper may be useful in engineering practice related to vibrations of circularly symmetric systems (in particular, gear wheels).