Wheel Center Research Articles

Wheel-INS: A Wheel-Mounted MEMS IMU-Based Dead Reckoning System

To improve the accuracy and robustness of the inertial navigation systems (INS) for wheeled robots without adding additional component cost, we propose Wheel-INS, a complete dead reckoning (DR) solution based on a wheel-mounted microelectromechanical system (MEMS) inertial measurement unit (IMU) in this article. There are two major advantages of mounting IMU to the center of a non-steering wheel. Firstly, the gyroscope outputs can be used to calculate the wheel speed, so as to replace the traditional odometer to mitigate the error drift of INS. Secondly, with the rotation of the wheel, the constant bias error of the inertial sensor can be canceled to some extent. The installation scheme of the wheel-mounted MEMS IMU (Wheel-IMU), the system characteristics, and the DR error analysis are all discussed in this paper. Experimental results show that the maximum position drift of Wheel-INS in the horizontal plane is less than 1.8% of the total traveled distance, reduced by 23% compared to the conventional odometer-aided INS (ODO/INS). In addition, Wheel-INS outperforms ODO/INS because of its inherent immunity to constant bias error of gyroscopes. The source code and experimental datasets have been made available to the community ( <uri xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">https://github.com/i2Nav-WHU/Wheel-INS</uri> ).

Stress behaviors of rib-to-deck double-sided weld detail on orthotropic steel deck

To clarify the stress behaviors at a rib-to-deck (RD) double-sided weld detail, controlled truck loading tests were first performed on a newly built long-span cable-stayed bridge with orthotropic steel decks (OSDs). A specifically designed truck loading scheme were employed to simultaneously obtain stress records at the outside weld of the RD detail. A solid FEM panel model was established to determine the stress at the RD double-sided weld detail. It was found that the stress at the detail under wheel loads was dominated by significant local effects, where the apparent stress at the details was produced if their distances to the wheel center were not larger than the rib spacing in the bridge transverse direction or the floorbeam spacing in the bridge longitudinal direction. In addition, each axle could produce an individual stress cycle only when the detail was underneath the deck plate covered by the wheel load distribution width. The FEM results indicated that among the three typically transverse loading locations, the riding-rib-wall loading was the most critical, and generated the highest stress range at the RD double-sided weld detail. The stress range at the outside weld of the detail was higher than that of the inner weld, hence stress measurements outside the detail could conservatively be used for evaluating the fatigue of existing OSD bridges that use the RD double-sided weld detail. The results also provided strong support for the FEM analysis of the OSD using a panel model loaded with a one-sided twin axle.

Parametric design of inner teeth of center wheel in electromagnetic harmonic movable teeth transmission

In order to improve the rationality and design efficiency of the structural parameters of the electromagnetic harmonic movable teeth drive system, the rationality of the set parameters is judged based on theoretical calculation, and visual programming is carried out by using VB. The designer only needs to input the set parameters into the specified dialog box to get the corresponding output results, which makes the design of the inner teeth of the center wheel more convenient and fast.

Wheel Hub Automatic Production System Based on Industrial Robots

In this thesis, a control system for a wheel hub machining line based on a Fanuc robot, which includes adopting Siemens 300PLC as the main control unit, performing wheel circumferential positioning and center correction based on vision technology, and controlling the machine tool to perform real-time tool compensation based on the measured data, is researched and designed to achieve fully automatic unmanned wheel processing.

The convective heat transfer characteristics of the track surface on which wheels roll over periodically

The convective heat transfer coefficient on the rail surface is an important parameter to determine the temperature field of the wheel/rail contact region, especially at the condition that train operates normally and the condition that an eddy current brake is used. Because of the complex configuration of a real wheel/rail contact system, it is hard to build a model with similar geometry as the real one. In this paper, a simple experimental model is used to obtain the convective heat transfer coefficient on a circular track surface on which the wheels pass periodically. In the experimental processes uniform heat flux is applied on the track surface, and the six types of the wheels are used. The results show that when the heat transfer coefficient is presented regarding to the wheel center velocity or angular velocity, it is dependent on the wheel diameter. For the same wheel diameter, the heat transfer coefficient has a parabolic distribution characteristics regarding to the wheel center velocity, which means the heat transfer coefficient increases firstly and then decreases as the wheel center velocity increases. The maximum value of the heat transfer coefficient is independent of the wheel diameter. It is hard to find a correlation between Nusselt number and Reynolds number for the wheels with different diameters. The significant characteristic is that the frequency of the wheels pass takes a major role on the heat transfer coefficient. Therefore, the heat transfer coefficient can be correlated with the frequency of the wheels that run over the circular track.

Accelerometer-Based Wheel Odometer for Kinematics Determination

Various high budget industries that utilize wheel-based vehicles rely on wheel odometry as an integral aspect of their navigation process. This research introduces a low-cost alternative for typical wheel encoders that are typically used to determine the on-track speed of vehicles. The proposed system is referred to as an Accelerometer-based Wheel Odometer for Kinematics determination (AWOK). The AWOK system comprises just a single axis accelerometer mounted radially at the center of any given wheel. The AWOK system can provide direct distances instead of just velocities, which are provided by typical wheel speedometers. Hence, the AWOK system is advantageous in comparison to typical wheel odometers. Besides, the AWOK system comprises a simple assembly with a highly efficient data processing algorithm. Additionally, the AWOK system provides a high capacity to handle high dynamics in comparison to similar approaches found in previous related work. Furthermore, the AWOK system is not affected by the inherited stochastic errors in micro-machined electro-mechanical systems (MEMS) inertial sensors, whether short-term or long-term errors. Above all, the AWOK system reported a relative accuracy of 0.15% in determining the distance covered by a car.

Influence of ovality of the wheel center on the stressdeformed condition of the “bandage-center” connection of the eleсtric locomotive wheel

Influence of ovality of the wheel center on the stressdeformed condition of the “bandage-center” connection of the eleсtric locomotive wheel

Development of a mathematical model of dynamic characteristics of a drive with a planetary mechanism

The article is devoted to the development of a mathematical model of dynamic characteristics of a drive with a planetary gear mechanism. The subject of research is a drive with a planetary gear mechanism. The following issues were considered in the article: the synthesis of a planetary gear mechanism; the development of a mathematical model that describes the dynamic characteristics of the system; the determination of the dynamic characteristics of a drive with a planetary gear mechanism. Research is based on the method of determining the number of gear teeth; the method of determining the kinetic energy of the James gearbox; the method of determining the dynamic characteristics of an electric motor. The possible number of satellites is given in the article; the pitch radii of the wheels for a given modulus are defined; the moment of inertia of the mechanism reduced to the movable central wheel is determined; a mathematical model of the motion of a drive with a planetary gear mechanism is developed. Equations of motion of a drive with a planetary gear mechanism were obtained. Assuming, in a particular case, all the links of the drive with the planetary gear mechanism as rigid links, a mathematical model was developed for this system, considering the dynamic characteristics of an electric motor. A mathematical model was developed that describes the dynamic characteristics of the system. Analytical solutions for the developed mathematical model are given.

Supply channels in planetary rotary hydraulic and pneumatic machines with central wheel wave numbers different by unit

The physical criteria limiting the size of the channels, including the conditions excluding the fl ow of the medium between adjacent cameras "under the satellite", are considered. The comparison of the variants of the channels execution is carried out: in the end wall of the epicycle; in the end wall of the sun gear; in the cylindrical toothed surface of the sun gear. The design criteria that characterize the relative sizes of the channels have been refi ned. For any planetary rotary machines with the number of waves N of the epicycle, which exceeds the number of waves M of the sun gear by two (N – M = 2), the channels should be located at the ends of the epicycle, but with N – M = 1, the relative cross-sections of the channels in the cylindrical toothed surface of the sun gear are much larger than in the end wall of the epicycle, therefore, for a planetary rotary machines with a low pressure of the medium, for example, vacuum pumps, it is advisable to make the channels in the cylindrical toothed surface of the sun gear.

Building a Maximal Independent Set for the Vertex-coloring Problem on Planar Graphs

We analyze the vertex-coloring problem restricted to planar graphs and propose to consider classic wheels and polyhedral wheels as basic patterns for the planar graphs. We analyze the colorability of the composition among wheels and introduce a novel algorithm based on three rules for the vertex-coloring problem. These rules are: 1) Selecting vertices in the frontier. 2) Processing subsumed wheels. 3) Processing centers of the remaining wheels. Our method forms a maximal independent set S1 ⊂ V (G) consisting of wheel's centers, and a maximum number of vertices in the frontier of the planar graph. Thus, we show that if the resulting graph G′ = (G − S1) is 3-colorable, then this implies the existence of a valid 4-coloring for G.

P.039 Cell type-specific DNA methylation is associated with childhood attention-deficit hyperactivity disorder symptoms

We analyze the vertex-coloring problem restricted to planar graphs and propose to consider classic wheels and polyhedral wheels as basic patterns for the planar graphs. We analyze the colorability of the composition among wheels and introduce a novel algorithm based on three rules for the vertex-coloring problem. These rules are: 1) Selecting vertices in the frontier. 2) Processing subsumed wheels. 3) Processing centers of the remaining wheels. Our method forms a maximal independent set S1 ⊂ V (G) consisting of wheel's centers, and a maximum number of vertices in the frontier of the planar graph. Thus, we show that if the resulting graph G′ = (G − S1) is 3-colorable, then this implies the existence of a valid 4-coloring for G.

Transient oscillatory processes at the balancing device operation of abrasive wheel grinder

In conditions of the practice development of building new production facilities following the concept of Industry 4.0 and the intensification and complication of production processes, the need for a general reduction in costs arises. One of these problems is the lengthening the life of supports of abrasive wheel grinding machines based on the balancing process automation without stopping the machines for maintenance work. This paper proposes a method for numerical calculation of the motion path of the grinding wheel spindle axis during the balancing process. Based on the proposed method, a numerical calculation was carried out and the motion path of the grinding wheel centre was built. As a result of the work, a transient balancing oscillatory process of a damping mode was built. This process does not lead to the forcing of the system in the eigenmode range, which creates prospects for the introduction of this balancing method in the grinding process and reducing production costs.

Bucket wheel excavators: Dynamic response as a criterion for validation of the total number of buckets

An original method for validation of the number of buckets on the working device of a bucket wheel excavator based on the dynamic response of its slewing superstructure (SS) is presented. A set of 16 seemingly acceptable solutions which satisfied the rigid design restrictions, based on the preservation of the existing (a) bucket wheel drivetrain, (b) theoretical capacity, (c) characteristics of the excavated soil and (d) position of the superstructure centre of gravity (CoG), was analysed. Already on the basis of the limiting vertical and lateral accelerations of the bucket wheel centre, which represents a well-grounded indicator of its dynamic behaviour prescribed by the code DIN 22261-2, 14 out of 16 analysed design variants have been discarded, reducing the set of possible solutions to only two – the originally-designed variant (with 17 buckets), and the variant with 20 buckets. Conclusions on the validity of these two design variants were derived on the basis of the dynamic response analysis of the referent points of the SS. The analysis of the impact of soiling on the dynamic response of the SS has shown that negative dynamic effects, observed in the preceding analysis of the originally-designed solution, increase with the amount of the adhered material. Although the redesigned variant with 20 buckets has proven as the only suitable solution from the standpoint of dynamic behaviour of the SS, the results have to be assessed carefully due to the fact that the reduction of the mass of the bucket wheel steel structure by more than 14% leads to the appearance of unfavourable dynamic effects, even though the SS CoG position is preserved.

Effect of offset of the crucible center with wheel center during planar-flow-melt-spinning process

Planar-flow-melt-spinning process (PFMS) produces amorphous ribbons for lamina of transformer core. However, the amorphous structure depend process parameters. The present work investigates the effect of offset of the crucible center to the wheel center, on puddle-formation and ribbon-thickness. Ribbon thickness is observed to increase to 13% and 10% respectively for an offset of 4 mm to wheel center in the clock-wise direction and in the anti-clockwise direction of rotation of the wheel. The preferable position of the crucible is its center being collinear with wheel center and the limiting offset of not>4 mm to the left of wheel center.

Heat Conduction and Temperature Rise for a Planar Movable Tooth Drive

Abstract Planar movable tooth drives have a compact structure. However, as the size decreases, the heat dissipation capacity decreases; therefore, temperature control is required. A heat conduction model of the drive system, including the central wheel and movable tooth, is established, and the meshing point of the movable tooth and center wheel is considered the heat source. The heat flux density at the meshing point is determined, and the analytical equations describing the temperature increases of the center wheel and the movable tooth are derived. The effects of the input power and system parameters on the temperature increase of the system are analyzed. The results show that the temperature difference of the movable tooth is about 1.5 times the temperature of the center wheel, and the temperature increase near the heat source decreases by more than 15 °C as the movable tooth radius increases from 2 mm to 2.5 mm. The movable tooth radius and center distance have significant effects on the temperature increase and can be used as control parameters to prevent a temperature increase of the drive.

Modeling of kinematics and kinetostatics of planetary-lever mechanism

The article provides analytical formulas for determining the kinematic parameters of a planetary-lever mechanism with one and two degrees of mobility. The obtained formulas were realized on a computer, in the program Math CAD 15. According to the results of calculations on a computer, regularities were established for the change in the kinematic parameters of the links of the mechanisms under consideration. The influence of the direction and magnitude of the angular velocity of the central wheel on the kinematic characteristics of the planetary-lever mechanism with two degrees of mobility has been determined. Formulas are created to determine the reaction in kinematic pairs of a planetary-lever mechanism with one degree of motility. Based on the calculation results and analysis provided, regularities of the reaction change in the kinematic pairs, as well as balancing moments in the carrier, were established during the basic geometric parameters of this mechanism were varied.

Reinvestigation into railway wheel-track interaction and suspension damage

Without considering either velocity or acceleration effects, the current conventional method presented in literature applies the vertical deflection of a wheel centre caused by a flat defect to the Hertzian contact theory. This method has been numerically and theoretically proved to be inappropriate and can incorrectly predict a higher wheel-rail impact force for a low speed than a high speed. Therefore, under a hypothesis of no wheel bouncing and sliding, two new methods, the velocity-based and the acceleration-based have been proposed. The former method takes the wheel centre deflection change in each computational increment from the Hertzian contact theory while the latter applies the wheel centre acceleration caused by the flat in revolutions to the wheel as a force in dynamic simulation, which interprets the speed effects on impacts precisely. A sensitivity study proves that the velocity-based method is unreliable as opposed to the acceleration-based method. A beam/rigid FE model has also been developed to inspect the wheel-track interaction by performing dynamic analysis in the time domain. It has been found out that the impact responses predicted by the FE analysis and the velocity method are similar and the FE results heavily depend on the compute increment, which implies the FE modelling in ABAQUS may be unreliable for this issue with current applied increments. Finally, the results calculated using the acceleration method have been employed to study the suspension/damper torsional stress caused by a wheel flat. This indicates that a wheel flat may lead to potential fatigue damage if without proper maintenance management.

Positioning of the Mobile Phone to Minimize Driver’s Biomechanical Effort During Navigation: DHM-Based Approach

The use of mobile phone as a portable navigation system gained momentum in recent years due to the advancement in GPS technology. Although mobile phone is a major cause of distraction, its complete elimination is impractical, as it has become an inevitable part of driving, particularly for the drivers of Mobile Application-Based Taxi Services. While literature pertaining to onboard navigation systems are available, there is rarely any recommendation for optimal positioning of mobile phone (as portable navigation system) to minimize distraction. Earlier studies have considered a limited number of positions in comparison to those adopted by the drivers in practice. Moreover, the driver’s comfort in terms of biomechanical effort and reachability is still unexplored. Thus, the current research aims to identify the optimal in-vehicle positioning of mobile phone, based on the minimal requirement of head and/or torso movement (rotation, flexion/extension) and fingertip reachability. Three manikins of different percentiles were used for evaluation of viewing and operating the mobile phones in each of the nine positions using the CATIA software. Results showed that position ‘8’ (center of the steering wheel) and position ‘4’ (right side of the steering wheel) were more suitable, whereas position ‘9’ (below the central console) was unfit for keeping mobile phone in terms of the biomechanical effort of viewing and reachability.

Accuracy Analysis of RV Reducer Eccentric Shaft Follow-Up Grinder

Eccentric shaft follow-up grinder is the core equipment in the process chain of eccentric shaft machining. In the process of grinding, the establishment of the kinematic model and the determination of the kinematic relationship of the C-X axis follow-up grinding directly affect the quality of the grinding process, and there are many error factors in the grinding process. It is very important to analyze the influence law of these factors on the quality of the workpiece. Through the mechanism of the error in the process of machining, which is caused by the change of X coordinate position, head frame rotation and wheel center eccentricity, the geometric relationship is established to solve the problem. The MATLAB simulation is carried out to find out the source of the error, so as to lay the foundation for the subsequent error compensation and achieve the purpose of improving the machining accuracy.

Design and FDM/FFF Implementation of a Compact Omnidirectional Wheel for a Mobile Robot and Assessment of ABS and PLA Printing Materials

This paper proposes the design and 3D printing of a compact omnidirectional wheel optimized to create a small series of three-wheeled omnidirectional mobile robots. The omnidirectional wheel proposed is based on the use of free-rotating passive wheels aligned transversally to the center of the main wheel and with a constant separation gap. This paper compares a three inner-passive wheels design based on mass-produced parts and 3D printed elements. The inner passive wheel that better combines weight, cost, and friction is implemented with a metallic ball bearing fitted inside a 3D printed U-grooved ring that holds a soft toric joint. The proposed design has been implemented using acrylonitrile butadiene styrene (ABS) and tough polylactic acid (PLA) as 3D printing materials in order to empirically compare the deformation of the weakest parts of the mechanical design. The conclusion is that the most critical parts of the omnidirectional wheel are less prone to deformation and show better mechanical properties if they are printed horizontally (with the axes that hold the passive wheels oriented parallel to the build surface), with an infill density of 100% and using tough PLA rather than ABS as a 3D printing material.