Epicyclic-type automatic transmissions are widely used in automobiles, it provide different speed ratio by control different elements to be an input or a fixedness with clutches and brakes. There are many researches about the Epicyclic-type automatic transmissions, but the research of the arrangement of clutches and brakes is fewer, and lacked for a method for arranging the desired clutches and brakes quickly. Therefore, the purpose of this research is to develop a methodology for arranging the desired clutches and brakes. First, introduce a planar-graph representation and a number sequence which had been used in arranging desired clutches and brake for years. Second, explore the relationship between contracted graph and epicyclic gear mechanisms based on topology theorem. Then provide a systematical procedure to arrange desired clutches and brakes into epicyclic gear mechanisms. With the above method, can find seven types of feasible clutching sequence that havn¡¦t been discovered in 94 types of feasible clutching sequence. Then, the number of the teeth of all gears can be calculated, as a result, five types of six-speed automatic transmissions are found. Finally, build the model of all the nine-link two-DOF epicylic gear mechanism that can be used in six-speed automatic transmissions.

An existing drivetrain model with clutch temperature dynamics has been used to simulate the behaviour of a heavy duty truck. During the implementation of the model in MATLAB/Simulink modularity and simplicity was greatly emphasized. This was done in order to facilitate the use of the model in various applications as well as making it easy to understand. The main contributions of the thesis is however the adaptation of a clutch temperature and wear observer for use in an on-line application in the gearbox management system (GMS). The process of taking the observer from an off-line simulation environment to running on-line includes taking into consideration the configuration and limitations of the GMS as well as adapting the interface of the observer. Concretely this means dealing with the limitations of the available data types in the GMS, compensating for the effect of biased measurements as well as accounting for the different dynamics of the sensor-types used in the clutch.In a simulation environment the performance of the adapted observer has been studied and its ability to compensate for heat expansion and wear in the clutch shown. / En existerande drivlinemodell med temperaturdynamik i kopplingen har använts för att simulera beteendet hos en lastbil. Vid implementation av modellen i MATLAB/Simulink betonades vikten av en enkel och modulär struktur. Detta gjordes för att underlätta användning av modellen i olika applikationer samt för att göra den lätt att förstå.De huvudsakliga bidragen i uppsatsen är anpassningen av en temperatur- och slitageobeservatör på kopplingen för användning i realtid av växellådans styrenhet. För att ta observatören från simulerings- till realtidsmiljö måste styrenhetens konfiguration och begränsningar beaktas samt gränssnittet hos observatören anpassas. Konkret betyder detta att hänsyn till begränsningarna hos de olika datatyper som används i kopplingens styrenhet tagits, att den negativa inverkan som brusiga mätsignaler kan få begränsats samt att skillnader i dynamik hos de olika sensortyper som används i kopplingen kompenserats för. Med simuleringar har prestandan hos den anpassade observatören studerats samt dess förmåga att kompensera för värmeutvidgning och slitage i kopplingen visats.

This master thesis focuses on design of steering wheel and clutch controller module for Formula Student car, The first part of this thesis is focused on communication protocol CAN and continues with explanation of reasons for development of this solution. Requirements for individual components of system are introduced in next part. At the end of the thesis the final electrical and hardware design is introduced as well as software design. The last part of this thesis is focused on simulation of system in race condition and evaluation of results.

MARTINOVSKÝ Peter: Identification and elimination of errors in the productions of bearings Diploma thesis elaborated in frame of engineering studies branch by means of identifying and eliminating errors in the production process of the clutch bearings using FMEA and Poka – Yoke. With the contribution of these methods are identified and eliminated the five most serious errors, which value of RPN exceeded a limits demanded by customers.

The primary goal of this work is to design and implement a clutch and brake system on the single tire Terramechanics rig of Advanced Vehicle Dynamics Laboratory (AVDL) at Virginia Tech. This test rig was designed and built to study the performance of tires in off-road conditions on surfaces such as soil, sand, and ice. Understanding the braking performance of tires is crucial, especially for terrains like ice, which has a low coefficient of friction. Also, rolling resistance is one of the important aspects affecting the tractive performance of a vehicle and its fuel consumption. Investigating these experimentally will help improve tire models performance. The current configuration of the test rig does not have braking and free rolling capabilities. This study involves modifications on the rig to enable free rolling testing when the clutch is disengaged and to allow braking when the clutch is engaged and the brake applied. The first part of this work involves the design and fabrication of a clutch system that would not require major changes in the setup of the test rig; this includes selecting the appropriate clutch that would meet the torque requirement, the size that would fit in the space available, and the capability to be remotely operated. The test rig's carriage has to be modified in order to fit a pneumatic clutch, its adapter, a new transmission shaft, and the mounting frame for the clutch system. The components of the actuation system consisting of pneumatic lines, the pressure regulator, valves, etc., have to be installed. Easy operation of the clutch from a remote location is enabled through the installation of a solenoid valve. The second part of this work is to design, fabricate, and install a braking system. The main task is to design a customized braking system that satisfies the various physical and functional constraints of the current configuration of the Terramechanics rig. Some other tasks are the design and fabrication of a customized rotor, selection of a suitable caliper, and design and fabrication of a customized mounting bracket for the caliper. A hydraulic actuation system is selected since it is suitable for this configuration and enables remote operation of the brakes. Finally, the rig is upgraded with the assembly of these two systems onto it. / Master of Science

Nowadays, the increasing amount of greenhouse gases and diminishing of the existing petroleum minerals for future generations, has led the automotive companies to think of producing vehicles with less emissions and fuel consumption. For this purpose, Hybrid Electric Vehicles (HEVs) have emerged in the recent decades. HEVs with different configurations have been introduced by engineers.The simulation platform aim for a parallel HEV, where the intention is to reduce the emissions and fuel consumption. The simulation platform includes an Electric Motor (EM) in addition to an Internal Combustion Engine (ICE). A new transmission system is modeled which is compatible with parallel configuration for the HEV, where the inertial effects of the gearbox, clutch and driveline is formulated. The transmission system includes a gearbox which is equipped with synchronizers for smooth change of gears. The HEV is controlled by a rule based controller together with an optimization algorithm as power management strategy in order to have optimal fuel consumption. Using the rule based controller, the HEV is planned to be launched by EM in order to have a downsized clutch and ICE. The clutch modeling is the main focus of this study, where the slipping mechanism is considered in the simulation. In the driveline model, the flexibility effects of the propeller shaft and drive shaft is simulated, so that the model can capture the torsional vibrations of the driveline. The objective of modeling such a system is to reduce emissions and fuel consumption with the same performance of the conventional vehicle. To achieve this goal first a conventional vehicle is modeled and subsequently, a hybrid vehicle is modeled and finally the characteristics of the two simulated models are studied and compared with each other. Using the simulation platform, the state of charge (SOC) of the battery, oscillations of propeller shaft and drive shaft, clutch actuations and couplings, energy dissipated by the clutch, torques provided by EM and ICE, fuel consumptions, emissions and calculation time are calculated and investigated. The hybridization results in a reduction in fuel consumption and emissions, moreover, the energy dissipated by the clutch and clutch couplings are decreased.

Many new cars are equipped with automatic transmissions. These gearboxes often have a dual clutch transmission (DCT) that has a built-in wet clutch. The lubricants used in these gearboxes is often very advanced because it must take care of two systems, the wet clutch and the gears. There is always a strive to make the drain intervals longer. To do this a fundamental understanding of the aging mechanisms inside a DCT must be understood. This project focuses at the aging of the lubricant and friction material inside the wet clutch. A test rig at Luleå University of Technology is redesigned to be able to age this kind of systems. The test rig contains a wet clutch from Volvo Construction Equipment and the redesign focuses mainly on decreasing the oil sump volume to 6 liter and getting the oil sump to be at 100 °C during the tests. To verify the test rig a test is done that are trying to mimic a test done on a test rig called ZF GK3. The same lubricant, friction material and grove pattern are used as in the test with the ZF GK3. Due to the difference in how the test rigs are built all parameters cannot be held the same during the test. At first the same sliding speed at the mean radius, the average power over an engagement and the oil sump temperature is kept the same. A drop in the static friction can then be seen over time. This was however not the expected behavior. The sliding speed is therefore increased which also increases the average power and transferred energy per engagement. This has also big effects on the temperature inside the clutch. A drop in the coefficient of friction can then be seen at 50 % of the sliding speed which also is seen on the test carried out on the ZF GK3. This verifies that the test rig can be used for aging of these kind of systems.The aging that takes place seems to be dependent on the temperature inside the clutch.

The thesis project was carried out in collaboration with the company Swepart and aimed to develop a concept for an engageable and disengageable clutch that would be mounted onto an engine driven power take off. A power take-off is the link that connects a vehicle's engine with machines that are to be driven, and since these power take-offs are often connected even when the machines do not need to be used, there are unnecessary losses in the form of increased fuel consumption. To eliminate these losses, the thesis investigated the possibility of integrating a clutch in the engine driven power take-off. To get an estimate of how much the clutch had to cost for it to be profitable, a study was made of what it costs for a typical truck to have a power take-off connected. During the project, a modified variant of Ulrich, Eppinger and Yang's product development method was used to develop a complete concept for the clutch. The modified method included five steps that were used to first identify the requirements that the clutch needed to meet, examine which clutch variants were best suited for the project work, develop concepts that could be compared and finally refined to arrive at a final concept. The final concept was presented in the form of a CAD model and consisted of a total of 18 components that had a height and width of 160 mm and a length of approximately 250 mm. The estimate of what it costs for a truck to have a power take-off connected turned out to be between 11,500 and 13,500 SEK per year.The final concept for the engageable and disengageable clutch was a combination of a single-plate clutch and a spline clutch that provides a smooth start-up, has a high-power transmission capacity, generates a small amount of heat, and is activated through pneumatic pressure. For the concept to be improved and manufactured for real, there are several future works that must be carried out. Among other things, material selection must be made for the various components of the clutch. FEM analysis must be done to see how the concept can handle high torques and temperatures. A cost analysis should also be carried out to see if the clutch becomes profitable to manufacture.

Detta kandidatexamensarbete syftar till att finna felmoder på Scanias kopplingssystem för framtida självkörande lastbilar. Detta görs genom att fokusera på ECA (Electronic Clutch Actuator), hävarm och lager. FMEA är en riskanalys som används för att kartlägga felmoder, felorsaker och deras feleffekter. Med en 10-gradig skala görs en bedömning med avseende på tre parametrar: felsannolikhet, allvarlighetsgrad och upptäckbarhet. Ett riskprioteringstal, RPN, fås genom att multiplicera dessa. Metoder som vi använt i vår studie är ett studiebesök på SCANIA, litteraturstudier och FEM-analys av hävarmen. De sex vanligaste felmoder som identifierats för lagret är utmattning, nötning (adhesiv och abrasiv), korrosion, plastisk deformation, elektrisk korrosion och sprickbildning/brott. De vanligaste orsakerna till lagerfel kan klassificeras till områdena smörjning, montering, hantering, design och driftförhållanden. Där innefattas bl.a. främmande partiklar (smuts, nötningspartiklar), monteringsfel, linjeringsfel, otillräcklig smörjning och överbelastning. All hantering av lager är viktig då lagerfel är en kombination av flera orsaker. Enligt experter är hävarmen välkonstruerad med hög säkerhetsfaktor. Den största orsaken till fel är på grund av intilliggande komponenter som exempelvis lager och ECA. Hög temperatur ökar spänningar och deformationer väsentligt. Bristande smörjmedel i lagren vid hävarmen har identifieras som en huvudorsak till funktionsfel. Enligt experterna från reparationsverkstaden fungerar ECA enheten smidigt med väldigt lågt fel sannolikhet. / This bachelor thesis aims at finding the failure modes at Scania's clutch system for future selfdriving trucks. The examined components are the ECA (Electronic Clutch Actuator), the fork and the release bearings. The FMEA- tool was used for the mapping the failure modes, their causes and effects. This assessment is made using a 10-grade scale with respect to three parameters: occurrence, degree of severity and detectability. A risk priority number RPN, is calculated by multiplying the aforementioned numbers. The methods that we used are a study trip to SCANIA's facilities, the relevant literature on the subject, and the FEM-analyses of the fork. The six most frequent failure modes identified at the release bearing are (fatigue), wear (adhesive and abrasive), corrosion, plastic deformation, electrically induced corrosion and fractures/crack formation. The most common causes for release bearing failures are classified into smearing, assembly, handling, design and runtime circumstances. They include among others exogenous particles (dirt, wear particles), assembly errors, misalignment, insufficient (grease) and excessive loads. All handling of the release bearings is important because release bearing errors have several causes. According to experts, the clutch fork is well-designd with a high safety factor. The most common failure mode causes are a result of interactions with neighbouring components e.g. release bearing and ECA. High temperatures increase the stresses and the deformation of the components substantially. Insufficient amount of lubricant in the release bearing is identified as the main reason of failure. According to experts from the repair workshop, the ECA unit works smoothly and with a low probability of error.

This thesis proposes that compliant mechanism theory can be used to design over-running ratchet and pawl clutches with reduced part count, lower assembly and manufacturing time while maintaining functionality. An extension of the theory to the micro regime is also briefly addressed. The results of the research show that the ratchet and pawl type of over-running clutch is a good choice for the use of compliance, and the clutch pawls should be loaded in compression to get the largest amount of output torque. It was found that com-pliant mechanism theory can be used to design ratchet and pawl clutches with fewer parts and lower manufacturing and assembly costs, and that these clutches perform comparable to traditional rigid-body ratchet and pawl clutches. Compliant ratchet and pawl clutches can replace traditional rigid-body clutches in some applications and now make it possible to be used in applications where it was once not economically feasible to use a over-running clutch. It was also found that these clutches function at the micro level.