Wheel Brakes Research Articles

Thermostatic interaction analysis of electric wheel brakes

Abstract The electric wheel needs to integrate the hub motor and brake in the wheel hub, so the integration scheme and structural parameters of each component in the electric wheel determine whether the electric wheel can coordinate the operation and the quality of the running performance. In this paper, the thermosolid interaction analysis of the brakes of electric wheels is carried out through ABUQUS software, so as to judge that the performance of the brakes meets the requirements, which will play a decisive role in the safety performance and life limit of the automobile, so as to effectively improve the working stability of electric wheels.

Measurement and Analysis of Brake and Tyre Particle Emissions from Automotive Series Components for High-Load Driving Tests on a Wheel and Suspension Test Bed

A current challenge in realising clean road transport is non-exhaust emissions. Important advances regarding measurement systems, including well-defined characterisation techniques, as well as regulation, will be made in the next few years. In this work, we present the detailed results of particle emission analyses, consisting of aerosol (size distribution, particle number (PN), and mass (PM)) and electron microscopy (EM) measurements, under different load conditions on a test bed for a wheel suspension and brakes. Standard tyres and brakes from serial production were tested with a high-load driving cycle, while particle measurements were conducted by gravimetric measurements and with a TSI SMPS, a TSI APS, and a GRIMM OPS. Furthermore, samples were analysed by electron microscopy. A bimodal particle size distribution (PSD) was obtained with an SMPS, with peaks at 20 nm and around 400 nm. The results of an EM analysis of >1400 single particles from the electrostatic sampler match the PSD results. The EM analysis also showed ultrafine particles, mainly containing O, Fe, Si, Ba, Mg, and S, and also fractal particles with high-C fractions. Our results suggest, in agreement with the previously published literature, that particulate emissions are related to the brake disc temperature and occur in significant amounts above a threshold temperature.

Invention of Electro Magnetic Eddy Braking System

Electromagnetic braking systems use electronic and magnetic power to apply wheel brakes. Our system utilizes the concept of electromagnetism in order to achieve braking without friction. Eddy braking improves the reliability &life of brakes since they do not wear out over time due to friction. This needs comparatively very less maintenance and no oiling. Electromagnetic brakingis an upcoming technological replacement for traditional braking systems. The main objective behind the proposed use of these eddy braking system in automobiles is that it is frictionless. This leads to a very low maintenance cost due to no friction and no oiling. Also traditional braking systems are prone to slipping while this one is guaranteed to apply brakes to the vehicle.

“Evaluation of an electromagnetically actuated drum brake concept”

In publications and conferences on the subject of wheel brakes, different concepts of electromechanically actuated wheel brakes can be found, as well as investigations into their suitability for the use in passenger cars. The vast majority of these brakes are disc or drum brakes, which are actuated by an electric motor. In the present publication, a brake concept is considered, that combines an electromagnetically actuated full-pad disc brake with a 10″ duo-duplex drum brake. The brake concept is researched in a project regarding brakes for autonomous shuttles and thus dimensioned using vehicle data of an example shuttle. The electromagnet was designed using finite element methods and the overall brake prototypically realized. The validation of the system design is carried out in component and system tests. The results show the suitability of the concept for the selected vehicle in terms of dynamics, installation space and energy requirements. However, there is a strong dependence of the braking torque output on the frictional sliding speed. Using hypothesis-based testing, electromagnetic effects like eddy currents are ruled out as a possible cause and the friction coefficient within the full-pad disc brake is identified as the main cause for the loss in torque. Consequently, the associated development conflict is identified and lies in the double function of the flux-carrying material in the electromagnet, which also acts as a friction partner for the braking disc.

Method for determining of aircraft landing performance by the simulation modeling

The paper considers the method for determining of aircraft landing performance, the basic of which is landing roll depending on the type and tire inflation pressure, runway surface condition, aircraft weight, availability of brake parachutes. The given results are received by the simulation modeling of aircraft spatial movement on a landing mode. The model of aircraft dynamics includes modules of aircraft movement kinematic parameters calculation, engine thrust, landing gear ground reaction, retarding force in wheel brakes and brake parachutes. Adequacy and reliability of the designed model of aircraft movement is confirmed by comparison of values of movement kinematic parameters obtained as a result of simulation modeling, and the parameters received from a real flight of the maneuverable aircraft. The designed simulation model allows us to analyze change of aircraft movement kinematic parameters, defining its flight mode. By the results of the conducted study, it has been defined that halving of normal operational pressure in MLG wheels decreases aircraft landing roll by over forty per cent. Installation of КТ-163D wheels instead of КТ-251А reduces landing roll by approximately a factor of one and a half times, use of brake parachutes reduces aircraft landing roll almost twice at landing on an icy runway. The introduced method is recommended to be used while studying aircraft landing performance during its design or modernization. It is also suggested to integrate the designed method for determining landing performance as a part of on-board information and control system with the view of immediate aircraft landing performance determination in real-time operation in specific flight conditions.

Ispitivanje parametara vozila u zavisnosti od tehničkog pregleda

In a strategic document of EU for Road safety improvement, up to 2030, "safe vehicle" is recognized as one of the pillars of a stable Road safety system. The part of the "safe vehicle" pillar is technical vehicle ispection, where parameters important for road safety are periodically checked. The aim of this work is to determine the quality of the measurement data and the ability to repeat measurements of some parameters during technical vehicle inspection, or more precisely, to determine whether measured data of turning wheel resistance and brakes ovality differ depending on the inspection place. The research is done by inspecting ten vehicles at five inspection places with different levels of resources use. The results show that the spread of measured data of turning wheel resistance is statistically significant and that it depends on the inspection place, as well as that measured data of turning wheels resistance significantly vary between inspection places. The measured percentage of brakes ovality is different from one inspection place to another, but the differences are statistically significant only for right wheels. The impact of inspection place, although less than in turning wheel resistance measurement, is still significant.

Functional Safety for Developing of Mechatronic Systems - Electric Parking Brake Case Study

The electric parking brake (EPB) system as the complex mechatronic system consists of the actuators that generate the clamping force necessary to hold the vehicle safe, the conventional calipers that convert clamp force into brake torque, electronic hardware with the Electronic Control Unit (ECU), cable harness and switches and especially the control software providing the functions that the driver will experience. Like most of the modern automotive components, the EPB is equipped with embedded electronic systems that include ECU, electronic sensors, signals, bus systems, and coding. Due to the complex application in electrical, electronics and programmable electronics, the need to carry out detailed safety analyses that are focused on the potential risk of malfunction is crucial for automotive systems. This paper describes a possible division of the EPB sub-functions between the supplier the wheel brakes and the supplier which supplying the ECU. Functional safety must be a guarantee with concerning the overall vehicle system. Functional safety is according to the requirements of the ISO 26262 standard and in the context of this paper relates solely to the E/E components (electrical and/or electronic) of the EPB. This paper covers the hazard analysis and risk assessment relevant to the EPB control software, and the derived allocation of ASIL risk levels to the EPB software elements of the functional architecture of the EPB.

Unsteady flow and aerodynamic behavior of high-speed train braking plates with and without crosswinds

Owing to continuous improvement in train running speeds, braking safety has become increasingly important, challenging braking approaches such as adhesion, eddy current, and electric magnet wheel brakes. Aerodynamic braking is an effective braking supplement whose braking effect is particularly outstanding in trains running at high speed. However, the flow field around the train can be significantly changed with the aerodynamic plate opening, degrading the aerodynamic performance of the train and even causing the train to sway violently. In this study, the unsteady aerodynamic characteristics of the full course of the braking plate, with and without crosswinds, were simulated and analyzed. The results show that pulse aerodynamic forces appear during the plate motion process, especially in the opening stage, and crosswinds increase the maximum values of these forces. Aerodynamic forces on the plate in the opening process are greater than those on the plate in the same position in the closing process. The difference in the flow field behind the plate in these processes is aggravated by crosswinds. Therefore, aerodynamic braking devices should be designed very carefully to minimize the impact of plate motion on the catenary and pantograph.

Selection of the torque – speed curves for the units of a wear-resistant brake system of high-mobility wheeled vehicles

With the growth of the power-to-weight ratio of the modern high-mobility wheeled vehicles, the capacity of their working brake systems is no longer sufficient for operation at the high speeds owing to high thermal loads of the brakes. In order to increase the average speed of the vehicle during the long-term downslope decelerations, as well as at the intensive use of the wheel brakes it is necessary to use additional devices – exhaust and retarder brakes. This kind of devices include the exhaust brake installed inside the internal combustion engine and the transmission hydro- and electrodynamic brakes (retarder brakes). The use of an electric machine operating in generator mode for storing the braking energy in an electric storage device is also a promising option. The combination of such additional devices is called “a wear-resistant brake system”. The research is focused on the selection of the torque – speed curves of a wear-resistant brake system providing higher average speeds of the wheeled vehicles and lower loads of the working brake system. Selection of the torque – speed curves of the units of a wear-resistant brake system is carried out by the analysis of the wheeled vehicle operation in different driving cycles which are close to its real operation cycles. These cycles are usually generated for a stationary case with the use of a quasi-stationary mathematical model of the vehicle motion. In the model, the vehicle – terrain interaction is described by means of the equations of the vehicle motion including stochastically generated roads. The analysis of the vehicle operation in different driving cycles provides stochastic data on the loads of the wear-resistant brake system as a whole, which allow selecting the torque – speed curves of its units depending on their operational features. The proposed method provides selection of the required torque – speed curves of the wear-resistant brake system units: the internal combustion engine (operating in the brake mode), the electric machine, and the retarder. Selection of the parameters of the electric machine is the first step for the solution of the next important problem – selection of the required capacity of the electric energy storage device. The results of the analysis provide selection of such combination of the characteristics for each unit of the wear-resistant brake system that will ensure the required deceleration of the vehicle.

Designing and Analyzing the Brake Master Cylinder for an ATV vehicle

A braking system is a means of converting momentum into heat energy by creating friction in the wheel brakes. The braking system which works with the help of hydraulic principles is known as hydraulic braking systems. The most frequently used system operates hydraulically, by pressure applied through a liquid. These are the foot-operated brakes that the driver normally uses to slow or stop the car. Our special interest in hydraulics is related to the actions in automotive systems that result from pressure applied to a liquid. This is called hydraulic pressure. Since the liquid is not compressible, it can transmit motion. A typical braking system includes two basic parts. These are the master cylinder with the brake pedal and the wheel brake mechanism. The other parts are the connecting tubing, or brake lines, and the supporting arrangements. The present paper is about designing of Twin master cylinder system for an all-terrain vehicle and doing a feasibility study of its strength using ANSYS. Our work is focused on reducing weight which is one of the factors to increase efficiency. Reduction in weight and space, due to its compactness. The twin Master cylinder system is a great advancement in the braking system for an ATV. 3-D CAD modeling is done using SOLIDWORKS 2017, whereas the analysis of its strength is done using ANSYS.

A Flight Simulator Study of an Energy Control System for Manual Flight

This article describes a flight simulator study to validate a new command control system for longitudinal load factor $n_x$ . The system is called nxControl and actuates thrust, speedbrakes, and wheel brakes that directly influence the total energy state of the aircraft. It aims at manually flying with higher precision and lower workload. After a brief overview of the functionality of nxControl and its cockpit interfaces, the key results of earlier proof-of-concept simulator studies are summarized. The focus lies on the comprehensive flight simulator study with 24 airline pilots to conclusively evaluate the complete system. The task was a highly demanding approach trajectory containing segmented-continuous-descent in gusty wind conditions, touch-down, deceleration, and taxi as well as engine failure at low altitude. With nxControl, the pilots achieved higher precision in airspeed and energy control with lower workload compared to conventional manual thrust control. In addition, nxControl achieved safety benefits in case of an engine failure.

TRAIL Spotlight

The first thing that you feel when an airplane lands is the effect of the brakes to slow it down. But, as the report “The Use of Wheel Brakes on Airplanes” points out, the use of brakes had to be proven to be safe before becoming part of standard operating procedures.

UTILIZATION OF THE AIRCRAFT FLIGHT DATA FOR ASSESSMENT OF THE AVIATION WHEEL BRAKES ENERGY STRENGTH

The utilization of flight data for assessing of the energy loading of aviation wheel brakes is proposed. The operational ranges of the main characteristics of the aircraft, which affect the load capacity of the wheel brakes, namely, landing speed, landing mass of the different aircraft using the flight data on-board means of objective control and registration (FDR), are studied.

A new control allocation algorithm to improve runway centerline tracking at landing

Abstract To achieve a high performance level during ground operations, the lateral dynamics of an aircraft must be controlled using all available actuators (rudder, nose wheel steering system and brakes), which gives rise to a challenging allocation problem. After an extensive literature review and evaluation of the most promising techniques, a novel and easily implementable control allocation technique is developed, which meets actuator and implementation constraints. It automatically manages the trade-off between minimizing actuator use and attaining the maximum virtual control. It is tested on a realistic on-ground aircraft model, which has been previously validated against a high-fidelity Airbus simulator.

ВЛИЯНИЕ ИЗНОСА РИСУНКА ПРОТЕКТОРА БЕГОВОЙ ДОРОЖКИ ШИНЫ НА ЕЕ СЦЕПНЫЕ СВОЙСТВА ПРИ ТОРМОЖЕНИИ НА СТЕНДЕ В БЛОКОВОМ РЕЖИМЕ

The PURPOSE of the article is to carry out an experimental study of the effect of the tire tread pattern wear on the implemented coefficient of adhesion to the support surfaces of the test bench under the variation of normal load value. METHODS. The studies were performed on the test bench of modular design, which allows to measure the normal and tangential reactions of the elastic tire with support surfaces. RESULTS. It has been determined that the increase of the tire tread pattern wear from 10 to 90% reduces the adhesion coefficient of the automobile wheel elastic tire by 35.3% when braking in the locked mode on a flat support surface. When the wheel brakes on one support roller of the test bench and the tread wear is from 10% to 90% the adhesion coefficient reduces by 18%. When the wheel brakes on two support rollers of the test bench the coefficient of adhesion makes 23.8% on the front roller and 48.4% on the rear support roller of the stand, with an increase in the wear of the tread pattern from 10% to 70%. CONCLUSION. The conducted experimental studies allowed to determine the dependence of the adhesion coefficient of the elastic tire on the wear degree of the tire tread pattern and the variation of normal load under the locked wheel braking on the flat support surface and one or two support rollers.

Wheel brakes for electric vehicles potentials and challenges

Wheel brakes for electric vehicles potentials and challenges

BRAKE OF THE FRONT DRIVE WHEELS OF THE TRACTOR "BELARUS"

The increase in the energy saturation of the new models of tractors "Belarus", as well as the mass of towed trailers and agro-technological tools that are mounted with them, required an increase in the efficiency of the tractor braking system. The purpose of the study is to increase the efficiency of the braking system of the wheeled tractor "Belarus MTZ" by creating wheel brakes for the front axle with minimal changes in its standard design. The developed drum brake with hydraulic drive of the front drive wheels of the tractor "Belarus MTZ-1221" does not require significant changes in the standard design of the front axle of the MTZ tractor and is adaptive to the anti-lock system, which operates on the basis of measurement and analysis of force factors. The design of the developed brake mechanism allows its adaptation to the anti-lock system, which operates on the basis of measuring and analyzing the forces that arise in the contact of the wheels of the front axle of the tractor with the supporting surface. The braking effect of the tractor "Belarus MTZ-1221" is provided by additional use of its coupling weight, which falls on its front axle. A set of design documentation for the drum brake for the front driving wheels of the tractor "Belarus MTZ-1221" was developed. The use of an additional traction weight of the tractor due to the wheel brakes of the wheels of the front axle of the tractor "Belarus MTZ-1221" will increase the efficiency of its braking, as well as increase the competitiveness of wheeled tractors produced by the JSC "Minsk tractor works". Bench tests confirmed the possibility of braking the calculated moments corresponding to the weight load on the front axle of the tractor "Belarus MTZ-1221". Consequently, the developed brake mechanism will ensure effective use of the tractive weight of "Belarus MTZ-1221" tractor.

철도적용에서 구동장치의 피로강도에 관한 시험적 연구

The truck that is used as running equipment for tank freight car support is a core structural part that supports the load of the car body and significantly influences the safety of freights and vehicles, as well as their running performance. Running equipment is composed of truck frames, wheels and wheel axles, independent suspensions, and brakes. Among these components, the truck frame supporting the load of the vehicles and freights may be the most important component. This study was carried out to analyze the structure of truck frames and to determine whether they are safe when the maximum vertical load, braking part load, and the front and rear load are applied to truck frames. This was achieved by subjecting the truck frames to stress tests and then measuring the stress on each part. The results of the stress tests showed that truck frames have a safe vehicle load design.

A Study on the Fatigue Test of Truck Materials for Railway Vehicles

The truck that is used as running equipment for freight car support is a core structural part that supports the load of the car body and that greatly influences the safety of freights and vehicles, as well as their running performance. The running equipment is composed of truck frames, wheels and wheel axles, independent suspensions, and brakes. Among these components, the truck frame supporting the load of the vehicles and freights may be the most important one. This study was carried out to analyze the structure of truck frames and to determine whether they are safe when the maximum vertical load, breaking load, and front and rear loads are applied to them. This was done by subjecting the truck frames to stress tests and then measuring the stress on each of their parts. Before the load test, a structural-analysis program was used for the stress distribution analysis of the truck frame. To measure the stresses based on the results of the structural analysis, strain gages were attached to the surfaces of truck frames [1].

Comparative analysis into the tractor-trailer braking dynamics: tractor with single axle brakes, tractor with all wheel brakes

AbstractThe paper elaborates a mathematical model in order to conduct a study into the dynamics of tractor-trailer systems during braking. The braking dynamics is analyzed by considering two versions for the braking system: 1) braking applied on the rear axle and 2) braking applied on all four wheels. In both versions the trailer is braked on all wheels. The mathematical model enables us to determine and graphically illustrate the evolution of the following parameters: braking deceleration, braking speed and the distance traveled by the tractor during braking. The mathematical model elaborated is applied on a tractor-trailer system completing transportation works.