This master’s thesis is focused on a design of test stand for servodrives loading. The theoretical part analyses state of art of load testing systems and describes main parts of workplaces. In the practical part is design of mechanical construction of workplace and electrical parts of machine. Master’s thesis also includes verification of properties of mechanical assembly and safety functionality verification.

This master’s thesis deals with utilization of biomass for micro cogeneration. The theoretical part of the master’s thesis defines main terms of the master’s thesis, which is biomass and cogeneration. The practical part of the master’s thesis is focused on the design and manufacturing of small micro cogeneration unit based on a small membrane steam engine. It means design of two steam generators to produce steam for the membrane steam engine. It will be also carried out design and production of membrane steam engine which is fitted with a small BLDC generator including electrical part for power output and measuring parameters. It will be made several measurements with the steam engine including measuring power output characteristic of the steam engine and measuring loading characteristics of the generator.

This diploma thesis deals with vibration of powetrain on dynamometer. For this problem I got six-cylinder engine, which is connected by flexible coupling to dynamometer. According to simplified computational model is this assembly simulated in MBS of system ADAMS View. Two versions of flexible coupling are dealt. In the final part of the thesis is created single program for calculation self-frequency of this assembly and in the end of this thesis is general evaluation.

The theoretical part consists of the introduction of company KOMPAN A.S. In addition, there are also introduced the main parts of production, especially CNC workshop, shop floor workplace and warehouse. In the experimental part there is introduced HPL material first. The following is a description of the testing including used tools and materials provided by Kompan Czech Republic s.r.o. Testing was focused on measurement of force load of instruments using piezoelectric dynamometer. The obtained data was processed and analyzed. The last part of the master's thesis is economic evaluation of the production of selected product, which consist of HPL panels. In the following discussion there are evaluate obtained results. In the conclusion part are summarized main results.

Diplomová práce je zaměřena na výběr pohonné jednotky pro Formuli Student, sestavení spolehlivého výpočtového modelu za využití pokročilého testování. Dále se zaměřuje na přípravu vhodných podmínek pro testování, samotné testování a následnou kalibraci řídicí jednotky pro validaci simulací a také pro efektivní a spolehlivé řízení motoru v náročných závodních podmínkách. Je zároveň součástí komplexního projektu, který se zabývá celkovým vývojem přeplňovaného jednoválcového motoru pro tým TU Brno Racing.

Title: Evaluation of the strength of selected muscle groups and the range of motion in sport aerobics athletes Objective: Sport aerobics belongs to group of sport gymnastics, which brings increased demands especially on joint mobility, muscle strength and coordination of movement. Athletes are selected according to these prerequisites the development of which is still supported by training. The thesis follow up the physical measurement of these attributes. The Aim: Evaluation of joint mobility and muscle strength of 12-16 year old sport aerobic athletes and their correlations. Furthermore, the comparison together with the level of the performance group. Method: Measurement of joint mobility using goniometry, hypermobility evaluation using Beighton score, measurement of the muscle strength using HUMAC isokinetic dynamometer. Comparison of measured results with performance group level. Results: During measurement of the joint range using the method goniometry was found, that in flexion of the hip joint had 100 % of the athletes increased joint motion. In hip extension, the joint range wasn't increased at all. Beighton score showed, that 90 % of athletes were constitutionally hypermobile. The relationship between joint range and the values of the muscle strength - peak torque has not been proven. Key...

Title: The influence of foam rolling on range of motion, strength of the knee extensors and flexors and H/Q ratio. Objectives: The aim of the diploma thesis was to determine the effect of the foam roller on the range of motion and strength of the extensors and flexors of the knee joint. The muscular strength of the knee extensors and flexors was determined using a Humac norm isokinetic dynamometer. Another goal was to determine the effect of the foam roller on the force ratio of extensors and flexors (H / Q) which is an important detail for the prevention of lower limb injuries Methods: This is an experimental study. The measured research group (n = 12) consisted of the students of the Faculty of Physical Education and Sport at the Charles University. A Black roll foam roller of medium hardness with a non-serrated surface was used. The range of motion of the knee flexors were measured using the sit and reach test and the knee extension test. The range of motion of the knee extensors were measured using a modified Thomas test and Ely's test. The isokinetic strength of the extensors and flexors muscles of the knee joint and the H/Q ratio were measured using a Humac Norm isokinetic dynamometer. Results: Measurements showed that the foam roller affected the range of motion of the flexors and extensors...

När en lastbil färdas på väg utsätts den för ett antal krafter. Däckens rullmotstånd utgör ungefär 36 till 60 % av färdmotståndet. Att kunna validera rullmotståndet vid egen testning är värdefullt för en fordonstillverkare som Scania. Däcktillverkare tillhandahåller en konstant rullmotståndskoefficient men det är oklart om den går att använda i beräkningar för Scanias testsetup.Provningen går ut på att undersöka om testuppställningen möjliggör uppmätning av däckens rullmotstånd på chassidynamometer med momentnav. För den experimentella delen av examensarbetet har en kvantitativ datainsamlingsmetod använts för vidare maskinell analys och manuellt utföra statistisk undersökning. Testdriven utveckling (TDD) har tillämpats för att utifrån testresultaten kunna arbeta iterativt.Vid testningen går rullmotståndskoefficienten upp, ner eller ligger stabilt. Detta beror på att Kistler (Kistler momentnav består av två fälgar som innehåller universalsensorer för att kunna mäta vridmoment) har elektrisk drift som korrelerar till spridning av uppmätt rullmotståndskoefficient. Kistler momentnav är inte repeterbart på grund av drift. Det är möjligt att kompensera för den elektriska driften i Kistler momentnav och beräkna rullmotståndskoefficienten baserat på sista analyspunkten från körningarna.Mätvärden från Kistler momentnav har spridning. Genom att beräkna medelvärde för rullmotståndskoefficienten fås bättre noggrannhet. Medelvärde indikerar att rullmotståndskoefficienten har inget eller litet hastighetsberoende.Det går att använda Kistler momentnav och chassidynamometer 2 som testuppställning för att mäta upp av däckens rullmotståndkoefficient. Det är möjligt för Scania att fortsätta använda denna testuppställning för att bland annat undersöka fler däck. / When a long haul truck travels on a road it’s subjected to a number of forces. The tires rolling resistance is approximately 36 to 60% off the total travel resistance. Being able validate the rolling resistance during own testing is valuable to vehicle manufacturers like Scania. The tire manufacturers provide a constant rolling resistance coefficient but it’s unclear if it can be used in calculations for Scanias test setup.The purpose of the testing is to investigate if the test setup enables measuring the tires rolling resistance on a chassis dynamometer with torque wheels. For the experimental part of the degree project, a quantitative data collection methodology has been used for further machine analyzation and manually performing statistical analysis. Test driven development (TDD) has been applied to work iterative based on the test results.During testing the value of the rolling resistance coefficient went up, down or was stable. This is dependent on the electrical drift Kistler have (Kistler torque wheel consists of two rims that contain universal sensors to measure torque), that correlated with the distribution of the measured rolling resistance coefficient. It’s possible to compensate for the electrical drift in Kistler torque wheel and calculate the rolling resistance coefficient based on the last analyzation point from the tests.The measurements from Kistler torque wheel are distributed. By calculating the average of the rolling resistance coefficients a higher degree of accuracy is obtained. The average indicates that the rolling resistance coefficient have no or a small speed dependency.It’s possible to use Kistler torque wheel and chassis dynamometer 2 as a test setup to measure the rolling resistance of the tires. It’s possible for Scania to continue using this test setup to investigate more tires.

Brake materials represent an important source of air pollution, especially in urban areas, where they can contribute to approx. 21 % of the traffic-related particulate matter emission. For this reason, the design of new brake materials with low emissions is a topical issue. In addition to low emissions, the design of new friction materials has to ensure excellent performance with stable coefficients of friction and low wear rate. Due to the several requirements that these materials need to fulfill, their development and testing are complex and intercorrelated. Good performance and low emission strongly depend on the mechanisms acting at the disc-pad interfaces. In this thesis, a brake dynamometer testing protocol is developed to better understand the relationships of the braking parameters with the brake performance and emission behavior, correlating them with the surface characteristics. The surface characteristics were investigated with a-posteriori analysis, in terms of extension of the contact area, degree of compaction of the wear particles and relevant composition. The work is focused on the bedding process and the influence of the braking parameters on the frictional, wear and emission behaviors. Regarding the bedding process, run-in, transition stage and steady states were identified as concerns the frictional, wear and emission behaviors. The frictional behavior gets stabilized by the extension of the secondary plateaus, whereas the wear and emission behaviors are stabilized as their degree of compaction increases. The influence of pressure and velocity under mild sliding conditions were studied for a low-met and NAO material, the two most common types of friction materials. The low-met material featured a more stable and higher friction coefficient and lower wear and emissions than the NAO material. The wear behavior is strongly affected by pressure for the NAO material, and for the low-met material, velocity is very influential. Emissions follow a cube relationship with velocity for both materials. The significant differences in the observed behaviors are explained in terms of the different features of the surfaces. The NAO material featured a smooth and uniform surface, with higher coverage than the low-met material, on which steel fibers play important adhesive and abrasive actions. From tests under mild sliding conditions of several friction materials sliding against cast-iron discs, a linear relationship is found between the specific wear rate and the emission factor. This relationship identifies a wear rate below 2.5 10-14 m2/N complying with the Euro 7 limitation of 3 mg/km/vehicle after 2034. Among the friction materials sliding against cast iron discs, the NAO material and only one friction material displayed an emission factor below the limit of 3 mg/km/vehicle. In addition, the emission factor of low-met material sliding against a cermet-coated disc was lower than this limit. These observations confirm that the NAO materials and coated discs are effective systems to mitigate emissions, whereas further efforts are required to improve the emission behavior of low-met materials. Interestingly, the low-met materials with a reduced presence of secondary plateaus featured higher wear and emissions. Regarding the brake performance, under severe sliding conditions, the NAO material displayed worse frictional and wear behaviors than the reference low-met material. For high-pressure ranges, the effect of pressure is to cause a monotonic decrease in the friction coefficient. The effect of temperature on the friction coefficient causes an increase in the friction coefficient when the tribo-oxidative processes are contained up to 300 °C. For combinations of high velocity and temperature, the tribo-oxidative processes are high enough to form a thick glaze layer on the surfaces. The glaze layers were correlated to a lubricating effect, or fade effect, at disc temperatures above 400 °C, especially when their extension covered the steel fibers. The cermet-coated disc displayed the same fade behavior at high velocity-temperature values, although at low velocities and high temperatures, friction instability was observed and related to larger but fewer patches originating to a significant extent from material transfer from the disc. The friction instability in the coated disc was ascribed to the different tribo-oxidative behavior in the formation of ‘glazes’ due to the low source of iron in the disc material.

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