Car Wheel Research Articles

Експериментальне дослідження опору кочення коліс автомобіля на роликовому стенді

The article considers the results of experimental studies of the rolling resistance of car wheels on a roller stand. Also, the dependence of the coefficient of total resistances during wheel rolling on the stand rollers on the speed was established. Monitoring and diagnosing the technical condition of the rolling stock of vehicles from the point of view of traffic safety is one of the most important problems. This control is especially important for systems whose technical condition affects traffic safety, first of all, brake systems, as well as the power unit in the traction test mode. Foreign and domestic experience testifies to the effectiveness of instrumental control. Its advantages lie in the reliability of the values of the checked parameters. The diagnostic equipment includes roller stands, on which you can check the braking and traction properties of cars. As shown by many studies, in particular, carried out at the Department of Technical Operation and Service of Automobiles, KhNADU (HADI), inertial stands provide more reliable information about the technical condition of the car. The inertial test method allows you to reproduce real speed and thermal modes of operation. To improve the accuracy of diagnosing a car on a roller stand, it is necessary to have an idea of the nature of the interaction of the car wheels with the stand rollers. Studies of wheel rolling on the stand rollers have been carried out by many authors since the 70s of the last century. However, all of these studies were conducted on old bias tires. Now, only radial tires are used on passenger cars, the rolling resistance of which on rollers has practically not been studied. Therefore, returning to the study of this issue is relevant. The rolling resistance of wheels on the rollers of the stand will significantly affect the nature of their interaction during long-term running tests (due to increased heating of contacting bodies, power losses, violation of similarity conditions, etc.). It was found that the value of the rolling resistance coefficient noticeably depends on the ratio of the radii of the roller and the wheel, as well as the contact load, that is, the radial force of pressing the wheel against the roller, and in addition, on the speed and duration of the mode. The obtained results of the experiment made it possible to improve the theory of the interaction of a car wheel with the rollers of an inertial diagnostic stand. Also, the results of the experiments can be extended to different types of tires and the ratio of the radii of the wheel and roller.

How do pedestrians distribute their visual attention when walking through a parking garage? An eye-tracking study

We examined what pedestrians look at when walking through a parking garage. Thirty-six participants walked a short route in a parking garage while their eye movements and head rotations were recorded with a Tobii Pro Glasses 2 eye-tracker. The participants’ fixations were then classified into 14 areas of interest. The results showed that pedestrians often looked at the back (20.0%), side (7.5%), and front (4.2%) of parked cars, and at approaching cars (8.8%). Much attention was also paid to the ground (20.1%). The wheels of cars (6.8%) and the driver in approaching cars (3.2%) received attention as well. In conclusion, this study showed that eye movements are largely functional in the sense that they appear to assist in safe navigation through the parking garage. Pedestrians look at a variety of sides and features of the car, suggesting that displays on future automated cars should be omnidirectionally visible. Practitioner summary: This study measured where pedestrians look when walking through a parking garage. It was found that the back, side, and wheels of cars attract considerable attention. This knowledge may be important for the development of automated cars that feature so-called external human-machine interfaces (eHMIs).

Analysis of Car Body and Wheel Geometry Depending on Mileage on the Wear of Tyres in Passenger Cars

This paper analyses changes in body geometry and related wheel geometry which may affect the wear of passenger car tyres. By means of an electronic device, changes were measured in the position of the spots that best reflect the changes of the body geometry. This included the front bench attachment, front suspension and rear suspension, at the beginning of the front stringers, at the end of the rear stringers, around the bulkhead, as well as the top mounting points of the McPherson struts. Changes were also identified in geometrical values for the suspension and steering system. The analysed parameters of wheel geometry included, among others, toe-in, inclination angles for all the wheels, camber and castors for front wheels, etc. Tire wear was characterized by the tyre tread size in the inner, middle and outer parts of all four vehicle wheels. Based on the results obtained, quantitative relationships were identified between the mileage of the vehicle, changes in the body geometry, changes in the suspension and steering system geometry, tyre wear and the coefficient of non-uniformity in tyre wear. It was concluded that changes in car body geometry were strictly correlated with vehicle mileage. These changes, in turn, directly influenced changes in wheel geometry which, apart from influencing vehicle safety, also contribute to excessive tyre wear.

Investigation on clinching assembly process of automobile wheel hub bearings

In this study, a precise and high-efficient clinching assembly strategy was proposed to improve the automobile wheel hub bearing’s reliability of service quality consistency. The structure of the wheel hub bearing was first improved to enable the requirement of axial working clearance. During assembly, the accuracy of each bearing was monitored online via micro-laser sensor to achieve precise and consistent axial working clearance. The effect of processing parameters were analyzed via simulation analysis. According to simulation results, it only cost 2.35 s to complete assembly process and the optimal clamping force of 38.8 kN was generated. The prototype bearings were manufactured and exhibited a reliable service life of more than 250,000 km, which verified the reasonability of the proposed clinching assembly strategy. Additionally, the assembly mechanism was further analyzed. The ferrite in the clinched hub shaft end was gradually lengthened and the cementite aggregation was improved.

Discrete fuzzy adaptive PID control algorithm for automotive anti-lock braking system

Due to the low slip rate and poor braking performance of automobile anti-lock braking system, a discrete fuzzy adaptive PID control algorithm for automobile anti-lock braking system is designed in this paper. Based on the theory of discrete fuzzy adaptive PID control algorithm, the braking force of a vehicle is analyzed and the anti-lock control target is set. The automobile adhesion coefficient and wheel slip rate are calculated as the input and output of the PID control algorithm to complete the control of the anti-lock brake system of the network automobile. Experiments show that the sliding rate of the discrete fuzzy adaptive PID control algorithm of the designed anti-lock system is close to 20%, which proves that the design method has good braking effect.

Дослідження взаємодії коліс автомобіля з роликами стенда при гальмуванні

The article discusses the issues of modeling conditions for obtaining diagnostic information about complex objects. As an example, the study of the braking qualities of four-wheel drive cars on an inertial roller stand is considered. Diagnosing the technical condition of cars from the point of view of traffic safety is one of the most important problems. This is especially important for systems whose technical condition affects traffic safety: especially braking systems. Foreign and domestic experience testifies to the effectiveness of instrumental control. The diagnostic equipment includes roller stands, on which you can check the braking properties of cars. As shown by many studies, in particular, carried out at the Department of Technical Operation and Service of Automobiles, KhNADU (HADI), inertial stands provide more reliable information about the technical condition of the car. Such stands allow you to reproduce the real speed and thermal modes of the brakes (especially those equipped with ABS). To improve the accuracy of diagnosing a car on a roller stand, it is necessary to have an idea of the nature of the interaction of the car wheels with the rollers. The studies of wheel rolling on the stand rollers have been carried out by many authors since the 80s of the last century. However, all these studies were carried out on uniaxial stands and for mono-drive vehicles. Nowadays, a large number of passenger cars have four-wheel drive. Rolling of the wheels of such cars on rollers and their interaction has practically not been studied. Therefore, a return to the study of this issue is relevant. A power model of the system of interaction between the car and the stand has been developed, taking into account the design features of the stand and the design features of the car's suspension. The power model of the system under consideration contains the equilibrium equations of the body and two bridges and the equations of motion of the rollers and wheels of the car. Based on the results of the analysis of the acting forces in the "car-stand" system, the braking moments on the wheels M and the coefficients of the use of the load q during the braking tests of a 4x4 vehicle were determined. The obtained research results allowed to improve the theory of interaction of a car wheel with the rollers of an inertial diagnostic stand.

ANALIZA ODDZIAŁYWANIA RÓŻNYCH WARTOŚCI CIŚNIEŃ W KOŁACH POJAZDU NA GEOMETRIĘ KÓŁ

The steering system in a vehicle is one of the main systems that ensures its controllability and is important for road safety. The steering system consists of two main mechanisms, namely the steering gear, the task of which is to convert the rotary motion into reciprocating motion, and the steering gear, the task of which is to ensure the correct steering of the vehicle. In this case, the steering system is interconnected with the suspension of the car, in which there are four main angles of the wheels that are responsible for the correct maneuverability of the vehicle, namely: camber angle, toe angle, angle of rotation of the axle of the fist and the angle of inclination of the pivot axis of the fist. Measuring the geometry of a vehicle's suspension has several interrelated purposes. One of them is the modification of the stability of the vehicle, that is, the effective impact on the maintenance of the vehicle on the road. Handling also depends on the geometry setting and ensures proper maintenance on the road. Well adjusted geometry ensures even tire wear on each axle. The purpose of the steering system is to maintain the correct position of the steering wheel in relation to the steering wheels. The tests were carried out in stationary conditions at the diagnostic station of the Rzeszow University of Technology using an automatic device for measuring and regulating the air pressure in the tires of the Unitrol PA-10K car and the Launch X-631 car wheel alignment system. The object of the study was a passenger car of the Opel Agila brand. The tests were carried out for various values of air pressure in the car wheels. Based on the above, the task was set - to demonstrate how incorrect air pressure in the wheels of a car changes the angles of inclination of the wheels of the car. When analyzing the obtained test results, it was found that the pressure in the wheels, different from the nominal, but the same in each wheel, does not significantly affect the change in the values of the parameters of the angles of inclination of the vehicle wheels. If the pressure in the wheels on one side of the vehicle drops by 1 bar, there is a significant difference in the camber angles of the front axle. Changes in the air pressure in one of the rear wheels of the car do not significantly affect the angles of inclination of the car wheels. KEY WORDS: AIR PRESSURE IN THE WHEELS, UNEVEN PRESSURE, WHEEL MOUNTING ANGLES, CAMBER AND TOE ANGLES, STEERING.

Digital mock-up and voice of the customer in the context of physical product development

Software development requires urgency in its launch in the market. Based on this, Agile Project Management has been introduced to reduce the time gap between idea and product release. Several studies have been developed to combine the qualities of Agile Management with those of the traditional Project Management for the application in physical products. Based on these studies, the following question has arisen: how can digital mock-ups be used to implement a hybrid (agile combined with traditional) project management approach, with customer participation, for physical products? In the present research, a development case study on a car steering wheel was conducted using digital mock-ups and the customer's voice. The study was applied to an audience of approximately 500 people. Results show the possibility of using digital mock-ups as a support for the development of physical products through the hybrid approach. For the generalisation of the method, more research must be conducted using different products from different areas.

DEVELOPMENT OF ROAD SURFACE BASED ON LOCAL RAW MATERIALS AND INDUSTRIAL WASTE

A review of the literature on the use of thermal power plants (TPPs) in the production of asphalt concrete was conducted. The advantages and disadvantages of asphalt concrete coatings are analyzed. According to experts, the reason lies in the violation of construction technology. And, in principle, the topics of ensuring compliance with construction standards and legislative regulation are among the most relevant in the construction of roads in Kazakhstan.The features of the use of asphalt-resin-paraffin waste from oil fields and ash of the Kyzylorda thermal power plant as part of asphalt concrete in road construction are considered. The construction of the pavement with the use of asphalt concrete based on the composite binder system "Bitumen - asphalt concrete-tar-paraffin waste (ARPW) - TPP ash" has been developed. Due to the stratification of the concrete mixture, the cement milk will be separated from the coarse aggregate, so the upper layer, which experiences the main loads and impacts from the wheels of cars, turned out to be without the main coarse aggregate. This subsequently led to its rapid wear and the formation of a rut. Cement concrete coating with all the positive aspects described below and obvious, and here, too, there are disadvantages of these types of coating, it is not the inability to open traffic immediately after the completion of construction and the need for expansion joints. The author reveals not only the advantages of asphalt concrete coatings, but also the disadvantage of asphalt mixtures in practical use in highways.

Influence of operating factors on the efficiency of the vehicle brake system

The main system responsible for the safety of the car is its braking system. The efficiency of the braking system is assessed by several parameters, the main of which is the maximum braking force, which is generated in the braking mechanisms, usually it is disc or drum types of brakes. The analysis of peculiarities of designs of existing types of brakes of cars is carried out, advantages and disadvantages of each of them, characteristics of application and maintenance are substantiated. The main factors that have a significant impact on the efficiency of the car's brake system have been identified. It was carried out the research of the influence of the main operational factors on the efficiency of the car's brake system: the pressure in the car's tires, contamination, and friction pairs of the brake mechanisms. The method of conducting experimental test lane and road researches of influence of the chosen factors on indicators of braking efficiency of the car is developed. Test lane experimental studies were performed using the Bosch BSA 4340 brake test equipment, graphs of changes in the braking efficiency of each of the car's wheels based on the researches were built, depending first on the change in tire pressure, then on the presence of rust, grit, and grime and level of wear of mechanisms. The quantity of the maximum braking force of the car depending on three quantities of pressure in tires of wheels was identified: the pressure recommended by the factory of 0,18 MPa, the lowered and increased pressures 0.15 and 0.25 MPa respectively. The influence of motor oil caught in the brake mechanism or treatment with special pastes on the value of the maximum braking force is also determined. The influence of the state of the brake discs and pads on the braking efficiency of the car was also investigated, the braking indicators were measured before and after the replacement of the brake disc and pads. On the basis of the conducted test line and road researches, conclusions are made and practical recommendations on prevention of reduction of brake efficiency of the car in the conditions of operation are offered.

Design and fatigue analysis of an aluminium alloy aerodynamic wheel

The deployment of CAx systems has a great influence on the design of individual car components. One of the components that must meet not only aesthetic requirements but also strict safety criteria, guarantee mechanical integrity and have good aerodynamic properties, is a car wheel. Before production begins, wheels must undergo a series of numerical analyses as well as experimental tests. Based on these tests, design modifications are made so that the wheel meets the safety criteria in real operation. The aim of this paper is to present the wheel design process, including the simulation of the rotary bending test using finite elements method (FEM). The paper describes boundary conditions of the numerical model, the process of finite element mesh generation and the results of linear static analysis and fatigue analysis of an aerodynamic wheel.

Hand vein recognition with rotation feature matching based on fuzzy algorithm

The Bodily motion or emotion, which can be obtained for example from a hand or a face, originates gestures. Every individual has a unique pattern of dorsal hand veins. The vein pattern's orientation changes when one rotates their hand in a particular direction. This study focused on hand-gesture recognition using dorsal hand veins. The aim of this work is a novel technique to track and recognizing hand vein rotation using fuzzy neural network, and the change in orientation was considered as a gesture and measured. The algorithms were tested over various rotations ranging from $-45^{circ}$ to $+45^{circ}$. We successfully detected various rotations in both clockwise and anti-clockwise directions, achieving $93%$ accuracy and a reasonable time execution. This problem can be solved because a person can steer a car wheel merely by rotating his/her hand. An infrared camera captured the rotation of hand veins, so car wheel steering was unnecessary.

Car wheel models using the distributions laws of forces on a contact patch with the road surface

It is natural to consider the rolling dynamics of an automobile wheel when it interacts with the road surface. At the same time the most difficult and important task is to determine the force components applied to the wheel, such as the friction driving force, the drag force, the rolling and spinning resistance moments that occur in the contact spot from the side of the roadbed. The paper investigates the aspects of dry friction, rolling and sliding of an automobile wheel presented as a deformable body. In this case, it is of great importance to take into account the treads, which is reflected in the tire models. An important aspect is the study of the laws of distribution of normal stresses in the contact area. To solve practical issues of road transport, approaches based on the Magic Formula of Pacejka and calculation methods based on brush, ribbon and string models, in particular, the Brush model of Svendenius, are highlighted. The conditions of its applicability are obtained and justified.

Casting X-ray image segmentation based on deep learning

Aiming at the problems that the current image segmentation algorithm has low accuracy in realizing the internal defect segmentation of industrial castings and the algorithm is not lightweight enough, an improved industrial casting internal defect detection algorithm Effi-DeepLab based on DeepLabv3+ was proposed. This method used MBConv in EfficientNet to replace the original Xception module for feature extraction, making the feature extraction network more efficient and lighter. Aiming at the problem of small internal defects in industrial castings, the expansion rate of the hollow convolution in the atrous spatial pyramid pooling (ASPP) layer was redesigned. The convolution block was more robust to small targets; the low-order semantic information in the feature extraction stage was fully utilized at the decoding end to perform multi-scale feature fusion to improve the accuracy of small target defect segmentation. The experimental results show that the segmentation accuracy and mIoU of the Effi-DeepLab model in the internal defect image data set of the automobile wheel are 93.58% and 89.39%, respectively, which are improved by 2.65% and 2.24%, respectively, compared with DeepLabv3+, and has better segmentation effect. In addition, it is experimentally verified that the proposed algorithm has good generalization.

Динамо-механический анализ резин с минеральными наполнителями в сравнении с наполнителями, широко распространенными в шинной промышленности

The work is devoted to the study of nanocomposites based on synthetic (styrene-butadiene) rubber with different fillers not previously used. The issue of using composites with alternative fillers is being investigated. The results of experimental testing and analysis of thermo-visco-elastic behav-ior of styrene-butadiene rubbers filled by various mineral particles of micro and nanosize, as well as pyrolysis products of organic food waste, are presented. The filled elastomers discussed in this work are mainly used in the tire industry to improve the performance of tires. All samples were tested on a dynamo-mechanical analyzer (DMA). Temperature and frequency dependences of the dynamic modulus and loss modulus are plotted for each of the composites. The frequency charac-teristics corresponded to the real range of rotation speeds of the car wheel, and the temperature var-ied from –50 to +50ºC. A comparative analysis of the results obtained was carried out. The struc-tural mechanisms of the filler are not investigated. It is assumed that the principles of operation of the investigated fillers at the structural level are similar to those described in many works for clas-sical fillers. Based on the test results a conclusion about the preferable operating conditions for the considered materials was made.

Human-Centered AI to Support an Adaptive Management of Human-Machine Transitions with Vehicle Automation

This article is about the Human-Centered Design (HCD), development and evaluation of an Artificial Intelligence (AI) algorithm aiming to support an adaptive management of Human-Machine Transition (HMT) between car drivers and vehicle automation. The general principle of this algorithm is to monitor (1) the drivers’ behaviors and (2) the situational criticality to manage in real time the Human-Machine Interactions (HMI). This Human-Centered AI (HCAI) approach was designed from real drivers’ needs, difficulties and errors observed at the wheel of an instrumented car. Then, the HCAI algorithm was integrated into demonstrators of Advanced Driving Aid Systems (ADAS) implemented on a driving simulator (dedicated to highway driving or to urban intersection crossing). Finally, user tests were carried out to support their evaluation from the end-users point of view. Thirty participants were invited to practically experience these ADAS supported by the HCAI algorithm. To increase the scope of this evaluation, driving simulator experiments were implemented among three groups of 10 participants, corresponding to three highly contrasted profiles of end-users, having respectively a positive, neutral or reluctant attitude towards vehicle automation. After having introduced the research context and presented the HCAI algorithm designed to contextually manage HMT with vehicle automation, the main results collected among these three profiles of future potential end users are presented. In brief, main findings confirm the efficiency and the effectiveness of the HCAI algorithm, its benefits regarding drivers’ satisfaction, and the high levels of acceptance, perceived utility, usability and attractiveness of this new type of “adaptive vehicle automation”.

EVALUATION OF DYNAMIC QUALITIES OF MOVEMENT OF RE-EQUIPPED HOPPER CARS OF PILS OF LONG-TERM OPERATION

As part of the work, a theoretical and experimental study (based on running dynamic tests) of the running qualities of empty hopper cars, converted from cement trucks and mineral trucks, was conducted. Computer simulation of the dynamics of empty hopper wagons converted from cement and mineral wagons depending on the condition of the track, the technical condition of the wagons and the weight of the container, the repeated presence of maximum vertical deviations and horizontal deviations of the track. A significant disadvantage of the railway transport of Ukraine is the limitation of the speed of trains with individual freight cars in an empty state, which are equipped with carts model 18-100. Among the reasons for the descent of the wheels of cars from the rails are: malfunctions of the running gear of the cars (fracture of the side frames and spring beams of the carts, malfunctions of the roller bearings of the axle box), wear of friction damper elements, unacceptable deviations and upgrades. As part of the work, a theoretical and experimental study (based on running dynamic tests) of the running qualities of empty hopper cars, converted from cement trucks and mineral trucks, was conducted. Computer modeling of the dynamics of empty hopper wagons, converted from cement and mineral wagons depending on the condition of the track, the technical condition of the wagons and the weight of the container and studies of the dependence of the wheel stability on the east.

Forensic medical evaluation of dental-jaw injuries in cases of traffic accidents

Information about the differential diagnosis of human bodily injuries, which were formed when the body, wheel and bottom of a modern car came into contact with the body of a pedestrian; a person on the road surface, in the cabin of a modern car (driver and passengers), when a cyclist comes into contact with a car, in cases of combined types of car injury, is not enough. The purpose of the study is to increase the objectivity of forensic examinations by determining the criteria for assessing damage to the dental system in cases of the most common types of accidents: collision of moving vehicle with man; run over the body with a wheels or the bottom of vehicle; at an injury inside the vehicle on the basis of the analysis of morphological features and the mechanism of the specified damages. The archival materials of 130 forensic medical examinations of the municipal institution “Odessa Regional Bureau of Forensic Medical Examination” concerning victims of living persons and corpses as a result of traffic accidents that were accompanied by their injuries in the period 2015-2020 were used. The following research methods were used: anthropometric, morphometric, photographic, radiological, statistical. The article presents our own experience of improving the objectivity and provability of forensic examinations by determining the criteria for assessing damage to the dental system in cases of the most common types of vehicle: collision of moving vehicle with man; run over the body with a wheels or the bottom of vehicle; at an injury inside the vehicle on the basis of the analysis of morphological features and the mechanism of the specified damages. It is proved that according to the degree of gravity of physical injuries (health disorder or disability), damage to the dental apparatus in traffic accidents should be investigated only in cases of isolated injuries. In this case, fractures of the jaws, regardless of their nature, should be assessed as moderate injuries according to the criterion of long-term health disorders; Crown fractures, traumatic tooth dislocations, and soft tissue fatal wounds should be considered simple injuries that have caused short-term health disorders. Abrasions, bruises should be attributed to simple injuries. Thus, it is impractical to separately determine the severity of the injury of the dental system in cases run over the head with a wheels or the bottom of vehicle - in these cases, we always deal with gross, massive destruction of the bones of the skull.

RELIABILITY CRITERION AND A MODEL FOR DETERMINING THE OPTIMAL SPEED OF MOVEMENT ON AUTOMOBILE ROADS IN WINTER SLIDING CONDITIONS

The article presents a model for establishing the optimal speed of movement on highways, taking into account the determination of the braking distance in winter slippery conditions. According to the research results, it was established that the main criterion for the formation of road accidents on highways in winter slippery conditions is the drivers' underestimation of the adhesion qualities of road surfaces. The main criterion of the model under consideration is the interaction of the car wheel (braking distance) with the road (adhesion coefficient) and is a complex that characterizes the stability of the car rolling over on slippery surfaces and the driver's actions in making an effective decision and the duration of the reaction time. In the proposed mathematical model, the accident rate on a slippery road is estimated by the coefficient of adhesion of icy road surfaces, the value of the load or the average wheel pressure. Also, the frequency of load application, the amount of deflection of the coating (at an air temperature above +20 ° C), rolling resistance, the coefficient of adhesion of the car wheel to the coating. One of the main characteristics of the model is a subsystem - the average pressure p = Q / S (S is the area of the imprint of the wheel, cm²), etc. Thus, in the process of analyzing the results of the causes of road traffic accidents, the factors of the driver's reliability and the decisions made will be taken into account, which depend on the speed of vehicles in any condition of the road surface.

Toroidal variator with hydro-gas pressure mechanism for creating a holddown

The article presents an analysis of the existing constructions of automatic shift gearboxes (automatic transmissions) in modern cars and describes a new construction based on a toroidal variator with a hydraulically variable holddown. There is a rationale that in comparison with the traditional automatic transmissions, a new one has smaller mass- dimensions with the same possibilities of transmitting smoothly variable torque from the engine to the car wheels. The innovation of the construction consists in the mechanism for pressing the intermediate disk of the variator to the friction surfaces due to the controlled hydraulic actuator and a membrane that eliminates bulky pressing linkage in a traditional construction of the toroidal variators.