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The goal of this thesis is to analyze the current state of vehicle brakes construction, possibilities of measuring the brake power, braking deceleration and to analyze the influence of pipe diameter to the beginning braking force, based on data from the measuring in the dynamic cylindrical testing lab. In the first part are described braking systems and Czech and International legislation, which have to comply with all road vehicles. The section also describes ABS, the modern brake system elements and testing methods that measure the requirements of the braking effect. The next section discusses the methodology of measuring and describes the experimental cylindrical test at Czech Agricultural University in Prague. In this thesis, they are processed and evaluated the data obtained from the measurement. At the conclusion are summarized the findings from the data evaluation and overall assessment of the influence of pipe diameter to beginning braking power.

The thesis deals with the analysis and comparison of the braking distance and the braking deceleration of the tractor Zetor Forterra 12441 and the towed trailer BSS 10 in relation to its load. For a complex analysis, the measurement of air pressure in front of and behind the load air pressure regulator of the trailer was performed during the brake tests as well. The work also includes a description of the current vehicle braking systems, methods of performing brake testing and legislative requirements on brake testing. There is also the methodology of comparative tests themselves and their specifications described in the thesis. The values achieved by the measurement are confronted both with the legislative regulations valid until the end of 2015 and the regulation newly valid from 1st January 2016. The analysis of the measured values shows that the braking distance of the set is lengthening with increasing the weight of the trailer load.

This thesis deals with a summary and evaluation of the practical measurement of brake discs and pads. The work consists of two parts - theoretical and practical. The theoretical part describes the history of brake systems and existing knowledge about current trends in the design of braking systems such as EHB, BAS, SWT, and others. In the practical part there is graphical representation of the braking force dependant on timing of each brake disc in combination with different types of pads of different manufacturers. In the end, there is an overall evaluation of the results arising from the calculations and graphs.

This thesis is aimed for rating condition of used tires and pressure in the tires and final results of breaking mechanism and mainly breaking distance. In the theory part is an explenation how the breaking process works. Other things this thesis is about are factors which affects breaking distance and most advanced electronic breaking systems. The end of the teoretical part is aimed for possibility of determinating breaking distance in offroad conditions, and also specialized testing rooms. Goal of practical part is to measure in laboratory conditions on vehicle with following results of breaking distance on booth sets of tires with different depth of the pattern and pressure in tires.

The aim of this work is to investigate the potential of Laser-Induced Breakdown Spectroscopy (LIBS) for identification of visually unrecognizable braking tracks. Identification of these tracks is based on different chemical composition of tire tread in comparison to road surface. The investigation was divided in several sequential steps – selection of suitable chemical element and its spectral line for break tracks identification; determination of the limits of detection and threshold intensity respectively for the selected chemical element; verification of LIBS ability to detect braking tracks on a real braking track. This testing braking track was prepared by exactly defined and described conditions. The detection was performed in two ways – laboratory analysis of tire treads particles collected via adhesive tape and in situ analysis via mobile apparatus. Results of both measurements showed that LIBS is able to detect visually unrecognizable braking tracks. Concepts of the devices capable of routine braking tracks identification for both possibilities were introduced.

The thesis deals with the possibilities of identifying the relevant tire traces at the place of a traffic accident based on their physical characteristics. Braking traces on the road are one of the most important objective elements for accident analysis, their easy and accurate detection is very important for accurate accident assessment. With the increasing technical equipment of vehicles, especially with the introduction of newer generations of braking assistance systems, traces left by the tires become almost invisible to the human eye. It is therefore highly desirable that their detection should be not only as accurate as possible but also as easy and fast as possible, not only for forensic experts, but especially for members of the traffic police departments. In line with the development and introduction of new safety and assistance systems for vehicles should also be the development of means and methods of providing the basis for technical analysis of traffic accidents. Reality shows that the procedures, even if still functional, are practically identical for several decades, are dependent on the subjective capabilities of the documenting person. An essential element of the work, compared to the previously described measurement procedures, is the use of modern methods and devices at the highest known level of knowledge. The aim is to find and verify a simple, accurate, subjectively least influenced detecting method for tire traces on the road. A series of measurements confirmed the possibility of using the thermal camera at the technical level usually available at the place of the accident, under limited atmospheric and time conditions. In addition, laser-induced plasma spectroscopy and rLIBS were used. This method of detecting spotless tire treads can be marked as a minimally feasible documentary and at the same time as fast enough, based on the measurements made and the intended removal of defects of the instrument in the development phase of the prototype.

The diploma thesis deals with the issue of braking trucks at different loads. The theoretical part defines the basic construction of trucks, truck brakes, the braking process and the factors that affect braking, braking deceleration, and legislative requirements for truck brakes. The practical part describes the course of experimental measurements, the use of the technique, the place of measurement, atmospheric conditions and used trucks. At the end of the work, based on experimental measurements, the obtained values of braking deceleration of trucks are evaluated.

This diploma thesis is engaged in analysis of braking process of vehicles, especially heavy utility vehicles, with regard to their instantaneous weight. This thesis features survey and division of braking systems and function of brakes including schemes and descriptions. Also there is introduce of some systems improving vehicle properties. Furthermore this work puts mind to possibilities of examination of brakes, measurement of braking distance and braking retardation namely in brake test rooms or by outdoor driving tests including descriptions of particular methods and equipment. There is also mention about legislative requirements for braking distance and braking retardation. The conclusion of this thesis compares numerically predicted braking distance and real braking distance measured for factual vehicle during outdoor driving test

This thesis is devoted on passenger car tyres. Theoretical part covers description of production, construction and tyre parameters. Practical part is comprised experimental measurement of influence of tread grooves depth on achievable vehicle deceleration. First, it is focused on preparation conditions of measurement, with subsequent processing and evaluation of the data obtained.