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The article considers a dynamic mathematical model of a new method of componentwise diagnosis of the brake master cylinder of a “tandem” type of the hydraulic brake system. We propose a variant of how simulated various faults affect the output parameters of brake process on the basis of mathematical modeling.

Simulation model of the automobile braking system performance taking into account not only the wheel, brake pads, brake drum dynamics but the dynamics of the hydraulic brake system: the main hydraulic cylinder, the brake gear hydraulic cylinders has been presented. Effect of changing parameters of the braking system elements on the braking distance of the automobile has been considered. Road users’ safety relies heavily on effectiveness of vehicle braking system. Thus, braking system design is essential when designing a new vehicle. Modeling of the functionality of the designed system is one of the most important phases of design. Time and material expenses for imitational modeling are always less than actually producing models and conducting experiments on them. Experiments should prove theoretical abstracts stated while modeling. Thus, the imitational model should be well designed and adequate. Imitational model allows efficient operation of brake system with different system of control.

Go-kart, an agile and elegant vehicle which has become the one from many to acquire basic knowledge of the automobile. Students are very much fascinated towards Design and fabrication of karts to gain hands-on experience. These vehicles encompass all recommended aspects which are involved in lightweight passenger vehicles. Some of the major aspects are likely to be steering, brakes, chassis, transmission system and wheels. Brakes play a crucial role in terms of control and safety. Hydraulic brakes are the only type which aids in achieving minimum stopping distance and time. Use of hydraulic brakes in go-kart became mandatory as the pressurized fluid makes the driver apply less effort. This paper investigated the effect of pedal ratio, manual force and gross weight of the vehicle on stopping distance and stopping time. The result outcomes can be used for the selection of better braking parameter configuration. The reader can choose the value without confusion and design his/her kart accordingly so that it can perform better with ease.

Magnetorheological (MR) brakes, belonging to the class of electromagnetic brakes, have a potential to replace conventional hydraulic brakes owing to reversible, rapidly controllable torque characteristics. In this study, T-shaped rotor MR brake was considered due to their higher braking torque capability and compactness compared to other configurations of brake. Optimal design of the brake was performed considering brake rotor radius, rotor thickness, flange length, casing thickness, coil height and coil width. Magnetostatic analyses were performed for different combinations of parameters of the brake dimensions to compute the magnetic flux density generated in the MR fluid region and the torque ratio and mass were calculated. The optimum dimensions of the brake were determined based on maximization of torque ratio and minimization of mass of the brake using multi-objective Genetic algorithm optimization technique. Further, magnetostatic analyses of the T-rotor brake with optimal dimensions were performed and torque characteristics were compared with those obtained for brake with simple disk rotor. It was concluded that T-rotor brake produces higher braking torque compared to simple disk rotor type MR brake for similar dimensions.

The vehicles usage is increasing day by day due to the recent, technological development in the automotive field. In a competitive global market in order to survive, the reliability needs to be ensured, through a proper monitoring system. Brake system is one such control component, in which much focus is very much essential. An efficient brake system should provide reliable and effective performance in order to ensure the safety. If it is not properly monitored, it may lead to a serious catastrophic effect such as accidents, brake down, etc. Hence, the brake system needs to be monitored continuously. In this study, an experimental investigation was carried out for monitoring the brake system using vibration signals. An experimental setup which resembles the brake system was fabricated. The vibration signals were acquired under various brake condition such as good and faulty. From the acquired vibration signals, the features were extracted using statistical and histogram feature extraction techniques and feature selection was carried out. The selected features were then classifieds using a Naive Bayes and Bayes Net a classifier. The classification accuracy of all the algorithms were compared for finding the best feature classifier model for monitoring the brake condition.

Brake pedal feedback is important for drivers to judge the braking time. Electric vehicles replace hydraulic brake pedal with electronic brake pedal simulator. Such a simulator transmits brake signal with cables. Therefore, a new electronic brake pedal simulator is designed in this paper, which can allow the implementation of an arbitrary nonlinear pedal force characteristic with electromagnet and different combinations of spring. The brake pedal feedback generated by the pedal simulator was emulated with matlab/Simulink. Furthermore, the springs were optimized to determine the combination to make the feedback meet requirements suitable for drivers. The simulated results prove the excellent brake pedal characteristic with the optimal groups of springs.

In this paper a mathematical model developed for the identification of excitation torque acting on the IC engine flywheel is presented. The excitation torque gained through internal combustion of the fuel in the IC engine is transmitted from the flywheel to the transmission. The torque is not constant but variable and is a function of the crank angle. The verification of the mathematical model was done on a 4-cylinder 4-stroke diesel engine for which the in-cylinder pressure was measured in one cylinder and the instantaneous angular speed of the crankshaft at its free end. The research was conducted on a hydraulic engine brake. Inertial forces of all rotational parts, from flywheel to the turbine wheel of the engine brake, are acting on the flywheel due to the nonuniform motion of the flywheel. It is known from the theory of turbomachinery that the torque on the hydraulic brake is a quadratic function of angular speed. Due to that and the variable angular speed of the turbine wheel of the engine brake, the torque during one engine cycle is also variable. The motivation for this research was the idea (intention) to determine the instantaneous torque acting on the flywheel as a function of the crank angle with a mathematical model without any measuring and based on this to determine the quality of work of specific cylinders of the multi-cylinder engine. The crankshaft was considered elastic and also its torsional vibrations were taken into account.

The article presents the results of work on the design of the air brake for testing of industrial gas turbine engines with free turbine. Designing of the air brake was performed on the basis of existing units using the program CFD - simulation Numeca FineTurbo. During the design the air brake arrangement was determined, which allows to utilize the required power to the shaft of the free turbine, increases stall margin of the air brake by waisting of the meridional flow channel. It was also made designing of the outlet guide vane to remove the residual twist. Unified nozzle also was designed to provide the air brake work at necessary points on the characteristic.

safety in automotive engineering has been considered as a number one priority in development of new vehicle. A brake system is one of the most critical systems in the vehicle, without which the vehicle will put a passenger in an unsafe position. Temperature distribution on disc rotor brake and the performance brake of disc rotor is influenced by the air flow around the disc rotor. In this paper, the effect of air flow over the disc rotor is analyzed using the CFD software. The air flow over the disc rotor is increased by using a duct to supply more air flow over the disc rotor. The duct is designed to supply more air to the rotor surface and it can be placed in front of the vehicle for better performance. Increasing the air flow around the rotor will maximize the heat convection from the rotor surface. The rotor life and the performance can be improved.

The electromagnetic braking using eddy current was studied, focused on two series of aluminium as the brake disc which are A16061 and A17075. This paper presents the comparison for both series in a few varied parameters related to eddy current braking such as air-gap, number of turns and brake disc thickness. Optical tachometer has been used along with PULSE analyzer to capture the speed (rpm) and time (s). The findings shows that the smaller the air-gap, the larger of electromagnet turns and the thicker disc thickness is, will generate higher braking torque to stop the rotational motion of disc brake and give great performance for eddy current braking. Thos parameters that been evaluated also addressed a potential on expanding this knowledge to develop an electromagnetic braking system to replace the conventional braking system.