Jovanka Lukić

University of Kragujevac · Faculty of Engineering

The existence of masking effects for fore and aft vibration under two axial Whole-Body Vibration (WBV) broadband random vibrations of seated subjects was investigated. Subjects were exposed to two axis excitation in simulated driving condition. Initially, level of excitation was the same in the both direction. Subjects did not have the same sensati...

Previous studies of brake wear emission have primarily performed as laboratory testing, i.e. on the brake dynamometer, which may not accurately reflect real-world driving conditions, especially vehicle's dynamics. Different experimental designs have been developed to avoid that brake wear particles could be mixed with other non-exhaust emission sou...

Bearing in mind the important role of the suspension system in maintaining ride comfort, stability and safety of the car by transferring the forces and moments from the road to the car body in strictly determined manner, the aim of the research presented in this paper was to derive analytically the suspension force ratios. Two suspension ratios wer...

The existence of masking effects for fore and aft vibration under two axial broadband randomvibrations of seated subjects was investigated. Subjects had to adjust equal level of stimulus sensation. Level of excitation (0.55 m/s 2 r.m.s., 1.75 m/s 2 r.m.s. and 2.25 m/s 2 r.m.s.) and seat backrest position (position K inclined 14° with respect to ver...

Electric vehicles (EVs) are increasingly being used, as they are more environmentally friendly than conventional vehicles with internal combustion engines (ICE). Battery electric vehicles (BEVs) can be said to have zero exhaust emissions only if the electricity used to drive these vehicles is obtained in an environmentally friendly way. It is commo...

Sustainable development represents one of the primary strategic management challenges for organizations operating across various economic sectors. The production and utilization of transportation means aimed at reducing greenhouse gas emissions lead to an enhancement of environmental protection. Many automotive companies are deploying electric vehi...

Knowing and understanding the parameters influencing the concentration of particles created by brake wear, as one of the main contributors to non-exhaust emissions from vehicles, is important for the further development of systems on vehicles to reduce the concentration of particles, and also for further research in the field of developing new fric...

The aim of this paper is to present the design of the experiment to determine the most influential factors on the occurrence of non-exhaust emissions of PM2.5 and PM10 particles, namely those caused by vehicle's brake wear. The focus in this case is on the operating parameters of the braking process (vehicle speed, brake pressure and vehicle load),...

With the development of contemporary drive systems that have a lower or zero emission of exhaust products, a significant reduction in the harmful influence of traffic on the environment has been achieved, but today new pollutants have been identified on the vehicle. One of such non-exhaust pollutant are brakes whose wear can be a significant partic...

Driving comfort is one of the important factors for vehicle users. There is a lot of research related to comfort or discomfort in a vehicle but there is still no well-defined way to assess it accurately. In this paper, an assessment of vehicle comfort during fore-and-aft random vibrations was made based on measured and predicted r.m.s. acceleration...

"The analysis of the braking system from the aspect of ecology is becoming an important topic today, bearing in mind that there is environmental pollution by particles that occur during the wear of the brake pairs. The use of an inertial brake dynamometer is one of the methods used in measuring the concentration of formed particles. A review and an...

Steering and suspension systems of a motor vehicle have very important mutual connections that have direct influence on a vehicle’s steerability, stability, comfort and life expectancy. These mechanical and functional couplings cause an intensive interaction between the two mentioned vehicle systems on a geometrical, kinematical and dynamical level...

In parallel with the significant reduction of the impact of vehicles on the environment, the development of modern propulsion systems that have less and less harmful impact, new pollutants are being identified on the vehicle. One of the such pollutants is the brakes, which wear out and lead to the formation of particles that are released into the a...

Micromobility includes light vehicles such as electric scooters, bicycles, electric bicycles. It is becoming more and more common in cities, both because it is easier to apply and to reach a certain place faster. Micro vehicles produce a small amount of exhaust gases and emit low noise levels. They are characterized by the fact that they represent...

Car model, color, design, motor power, driving performance, is just some of the factors that influence the purchase of a new car. However, one of the most important task of vehicle manufactures is driver comfort. In the initial phase of designing a car, a posture of vehicle driver must be carefully considered, because a long-term driving can affect...

It is very important during production to take into account the requirements regarding to recycling of vehicles. On this manner it is possible reuse of consisting materials and optimization of End-of-Life Vehicles. In European Union has defined targets to be achieved in the future for the recycling rate of vehicles at the end of their service cycle...

This study investigates the influence of thermal conditions in an agricultural tractor cab on the operator's thermal sensation. The study was performed using computational fluid dynamics (CFD) software Star CCM+. To evaluate the microclimate conditions, parameter equivalent temperature (standard EN ISO 14505-2) was used and compared with the result...

Suspension system of a vehicle is one of the most important components of a vehicle that directly affects the safety, performance, noise level. Designing mechanisms of suspension system of the vehicle is a very complex task. At the beginning it is necessary to realize many requirements relating to the suspension system. McPherson suspension system...

Brake is a device for slowing or stopping the vehicle. The sound that occurs in the process of braking is very irritating for the driver. Brake systems of road vehicles as important factor in overall vehicle noise have attracted great attention. All global brake system manufactures are focused to the quieter brakes. This paper presents an analysis...

Automotive ergonomics is a set of knowledge which has a task to design a vehicle to make the passengers feel comfortable. Interior packaging represents an important stage in the vehicle design process, in order to enable the driver to every important aspect of movement. During the process of driving, the driver performs various movements of arms an...

Noise is unpleasant sound that can have harmful effect on people's health. Motor vehicles and working machines are mobile sources of noise, in which engine is one of the key elements that create noise. Engine noise can be divided into mechanical noise and combustion noise. Diesel engines are always considered to be louder, and, as such, they are us...

Problem of vehicle noise has been observed since the appearance of the larger number of vehicles on the roads. Drivers and passengers are exposed to constant noise and vibration originating from their own vehicles and all other vehicles participating in traffic. This paper reviews development of regulations that impose limits for vehicle noise. Chr...

Road traffic emissions are a major contributor to ambient particulate matter concentrations and therefore, these emissions are targeted through ncreasingly stringent European emission standards. These legal restrictions succeed in reducing exhaust emissions, but do not address “nonexhaust” emissions from brake wear, tire wear, clutch wear, road sur...

Widely used method for transient signal assessment were applied on time series of disk brake signal noise. Wavelet Transform (WT), Short Time Fourier Transform (STFT) and Continuous Wavelet Transform (CWT) were applied on time series signal of disc brake noise in order to get significant data to identify process of appearing of squeal brake noise....

As agricultural tractor size and speeds have increased during recent years, heavier loads are transported on public roads at higher speeds. With the combination of higher-energy level and more rapid deceleration, brake systems with excellent heat dissipation characteristics are required. Wet multiple-disc brakes have similar multipledisc constructi...

Braking system is one of the most important components of a vehicle on the road. This system has the task to bring the vehicle to stop or slow down. Friction brakes, during the braking process, convert the kinetic and potential energy into the thermal energy (heat). The basic components of braking systems, brake discs and brake pads, in a short per...

It has been proved in literature that there is no generally accepted method for the evaluation of characteristics and output parameters of the disc brake mechanism. This paper presents experimental research of disk brake subsystem with brake fluid pressure in the brake cylinder and disc speed as input quantities and brake torque and brake noise (ex...

Automobile disc brakes were intensively developed over recent decades, but at the same time the engine power, average vehicle speed, and hence the kinetic energy to be transformed into the brake, were significantly increased, too. A small part of the kinetic energy is transformed into sound energy and creates noise. Disc brake noise is a problem th...

The noise that comes from the road traffic, along with other emitters of environmental noise has a largely negative impact on quality of life. In the Republic of Serbia as in communities everywhere in the world, the noise that comes from the road traffic has become an increasingly noticeable and serious problem which is especially pronounced in lar...

Development of the braking system includes optimization of many aspects of its performance, including the propensity to generate noise, in order to meet the demands of customers. Modern vehicles, with a generally high share of the front (disc) with regard to rear (drum) brakes during braking process and with small wheels, require from disc brakes e...

Based on the conducted analyses, it has been proven that there is no generally accepted method for evaluation of characteristics and output parameters of drum brake mechanisms. Experimental research of he drum brake subsystem with brake fluid pressure in the brake cylinder as input quantity and brake torque as output quantity is presented in the pa...

Serbia has great potential for the production of the biogas, due to growing energy crops and livestock are the greatest potential of its agriculture. The use of biomass through anaerobic digestion to get the biogas, would reduce the need for the slate to import energy. environmental protection should be raised to a higher level, the economy would b...

Brake squeal phenomenon has been studied for nearly 70 years now. During this period, majority of tests were based on subjective assessments and measurements with a moving vehicle on the road. Over the years, many laboratory tests have been developed with a wide range of options and approaches. The modern brake noise dynamometer has become a sophis...

A model based dynamic simulation has a significant role during motor vehicle’s development. A role of modeling is very significant in the preliminary phases of design - in definition of governing parameters. In practice, it is usually assumed that the vehicle’s vibration parameters are constant during exploitation, which is basically incorrect. Nam...

This work presents a method for analyzing the noise and vibration problems caused by hydraulic pumps in vehicles. This methodology is based on experimental research and coherent analysis of observed systems. Experimental investigations are conducted in order to determine dominant excitation of hydraulic systems. Vibrations and sound pressure levels...

The electrification of conventional vehicles, ranging from passenger vehicles and trucks to ground vehicles such as agricultural tractors, construction equipment and military vehicles, can potentially offer improvements in fuel economy and emissions. Nearly all conventional vehicles are powered by a gasoline or diesel fueled internal combustion eng...

A catalyst convertor has maximal efficiency when it reaches working temperature. In a cold start phase efficiency of the catalyst is low and exhaust emissions have high level of air pollutants. The exhaust system optimization, in order to decrease time of achievement of the catalyst working temperature, caused reduction of the total vehicle emissio...

During the engine cold start, there is a significantly increased emission of harmful engine exhaust gases, particularly at very low environmental temperatures. Therefore, reducing of emission during that period is of great importance for the reduction of entire engine emission. This study was conducted to test the activating speed of the catalyst a...

Understanding the behavior of human body under the influence of vibration is of great importance for the optimal motor vehicle system design. Therefore, great efforts are being done in order to discover as many information about the influence of vibration on human body as possible. So far the references show that the major scientific attention has...

Human body behaviour under the influence of two-directional random vibrations is of great importance for optimal motor vehicle design. Efforts are being made in order to discover as much information about the influence of vibration on human body as possible. References show that the most attention has been paid to vertical vibration, although inten...

Fore and aft vibration is a phenomenon familiar to trucks. Primarily, it appears as a result of irregularities of engine operation, clearances and elasticity in transmission, road roughness, etc. In order to determine the effect on driver and passenger due to fore and aft vibration, investigations were performed on heavy-duty trucks (wheel formula...

Contemporary vehicles have to satisfy high ride comfort criteria. In order to determine appropriate human body model in driving condition field and laboratory investigations on passenger cars have been performed. In field research, dominant vibrations loading of passenger was determined by variance analysis of experimental results. The highest load...

Contemporary vehicles must satisfy high ride comfort criteria. This paper attempts to develop criteria for ride comfort improvement. The highest loading levels have been found to be in the vertical direction and the lowest in lateral direction in passenger cars and trucks. These results have formed the basis for further laboratory and field investi...

Contemporary passengers motor vehicles I1m'e to achieve a great deal of comfort requirements. Problems of noise and vibration reduction ill vehicles may be sol\'ed by choice of optimal power train (PT) suspension this paper an analytic methods developed. Also, global model of both reMele and PT is developed and analyzed. Experimental investigations...

This work presents a method to analyze the noise and vibration problem caused by hydraulic pumps of power steering systems and body control system of vehicle. This methodology is based on experimental research and coherent analysis of observed system. Experimental investigations are conducted to get data in order to determine dominant excitation of...