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Tyre Temper. Meauserement on Moving Vehicle with Use of Infrared Pyromether OS100
Morávek, David ; Rasch, František (referee) ; Blaťák, Ondřej (advisor)
Bc. David Morávek Tyre temperature measurement on moving vehicle with of infrared pyrometer OS100 MT, IAE, 2008, page 70, picture 41 Problemacy of recording the temperature and tyre pressure on driven car is processed in this diploma work. Suitable measuring chain was set up. Censor holders for this type of measurement were designed and produced. Driving exams and tests are depicted in this work, too. We came to the conclusion that tyre temperature depends on lengthways and transverse acceleration of the car and also on it’s load.
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Effect of Shock Absorber on Vehicle Limits
Jurka, Adam ; Blaťák, Ondřej (referee) ; Hejtmánek, Petr (advisor)
The aim of this master’s thesis is to evaluate the effect of shock absorber on vehicle limits. At the beginning of the thesis, shock absorber properties were described. Then computational model was created and manoeuvres for shock absorber behaviour were defined. Created mathematical model is based on quarter model of a car and excitation in form of road with a random profile is an essential part of the model. This model was used for evaluation of heave. After heave analysis, shock absorber behaviour during drive was investigated. Drive conditions were defined as set of handling manoeuvres. For the drive investigation, complete multibody virtual model of racing car was used. Based on drive investigation analysis, optimal damping characteristics for each manoeuvre were found. Furthermore, each optimal characteristic was compared for different manoeuvres. Obtained results were compared. As a conclusion, compromise damping characteristic was suggested with the aim to fit the combination of all defined drive conditions. Final part of the thesis was aimed at validation of the computational model. Data measured during real drive were used as an input for this validation.
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Influence of Steering Wheel Holding Techniques on Length of Driving Maneuver
Kašpar, David ; Kadula, Lukáš (referee) ; Mikulec, Roman (advisor)
This master’s thesis deals with the position of the hands on the steering wheel and its impact on the driving manoeuvre time. In the theoretical part, the correct sitting position of the driver, his seat and steering wheel settings were described. Furthermore, the analysis of the initial positions of the palms on the steering wheel was carried out as well as the positions that are recommended for quiet driving on the highway. These positions were analysed in terms of the ability to turn the steering wheel and to provide a range of turning in given positions. For the experimental measurements, a questionnaire for the passenger vehicle drivers was created. The responses were evaluated to construct the most common hand positions on the steering wheel. From the selected positions, test drives were conducted to determine the required time for manoeuvring or the time required for change of hand positions on the steering wheel to perform the manoeuvre.
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Influence of Aerodynamics on Vehicle Handling Performance
Hejtmánek, Petr ; Kaplan, Zdeněk (referee) ; Dundálek, Radim (referee) ; Píštěk, Václav (advisor)
The main aim of this dissertation was to develop a computational tool capable of evaluating the influence of aerodynamics on the handling of a vehicle. The methodology it uses is based on the simulation of driving manoeuvres with a single-track model of a vehicle, which was composed with an emphasis on minimizing the amount of necessary input parameters. This simple model, which allows the assessment of the influence of aerodynamics on vehicle dynamic and static driveability, therefore doesn’t require large amount of input data, which makes the acquirement of relevant values easier. The computational model was validated by extensive measurements of two driving manoeuvres defined by ISO norms (step steer input and steady state cornering). As a consequence of unsatisfactory initial validation results, the differences between measurements and simulations were analysed, which led to gradual enhancements of the model with additional inputs to achieve better accuracy of simulations. The final part of the thesis deals with the comparison of influences of individual aerodynamic parameters on vehicle handling and the assessment of overall significance of aerodynamics compared to other factors which were taken into account (tires, mass properties, steering etc.). This thesis was realized in close cooperation with Škoda-Auto.
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Vehicle Dynamics Measurement Analysis Using Mathematical Modelling
Blaťák, Ondřej ; Kledus, Robert (referee) ; Mazůrek, Ivan (referee) ; Kaplan, Zdeněk (advisor)
This doctoral thesis is focused in connection of measurement with a model in this meaning. Only relative easier measurable variables are measured on a vehicle and these variables make model inputs. This process can be improved by using dynamic filtering principles, where measured variables are used not only as model inputs, but they are used for the correction of a model motion too. We can obtain an optimal estimate of vehicle real behaviour during a manoeuvre with using this method. Linear discrete Kalman filter (dynamic filter) was used for the connection of the measurement with the mathematic model with regard to chosen model (planar linear single track model). The main task of Kalman filter is try to estimate the state of the discrete time depending process that is determined by the linear stochastic difference equation. Effective measurement system (based on CompactRIO unit) was built within the scope of this PhD thesis. This system is able to measure simultaneously a lot of quantities on the experimental vehicle. Velocity components (measured through optical correlative sensor Correvit), yaw velocity (measured through vibrating gyroscope), lateral acceleration, distance component (measured through MicrosatGPS system) are the basic measured parameters. Big attention was paid to obtain other important inputs of the mathematic model such centre of gravity position, moment of inertia, steering ratio etc. The last part of the thesis is oriented on the real connection of the measurement with the mathematic model. Formula Ford 1600 was used as the experimental car. The driving manoeuvre was arranged according to the norm ISO/WD 3888/2. Three versions of the Kalman filter were realised, which differs in the measured variables used for the mathematical model motion correction. Other possibilities, how to improve the process of state variables estimation eventually how to effective use this algorithm for vehicle parameters identification (cornering stiffness of the tires for example), are sketched in the end of the thesis.
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Influence of Steering Wheel Holding Techniques on Length of Driving Maneuver
Kašpar, David ; Kadula, Lukáš (referee) ; Mikulec, Roman (advisor)
This master’s thesis deals with the position of the hands on the steering wheel and its impact on the driving manoeuvre time. In the theoretical part, the correct sitting position of the driver, his seat and steering wheel settings were described. Furthermore, the analysis of the initial positions of the palms on the steering wheel was carried out as well as the positions that are recommended for quiet driving on the highway. These positions were analysed in terms of the ability to turn the steering wheel and to provide a range of turning in given positions. For the experimental measurements, a questionnaire for the passenger vehicle drivers was created. The responses were evaluated to construct the most common hand positions on the steering wheel. From the selected positions, test drives were conducted to determine the required time for manoeuvring or the time required for change of hand positions on the steering wheel to perform the manoeuvre.
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|
|
Effect of Shock Absorber on Vehicle Limits
Jurka, Adam ; Blaťák, Ondřej (referee) ; Hejtmánek, Petr (advisor)
The aim of this master’s thesis is to evaluate the effect of shock absorber on vehicle limits. At the beginning of the thesis, shock absorber properties were described. Then computational model was created and manoeuvres for shock absorber behaviour were defined. Created mathematical model is based on quarter model of a car and excitation in form of road with a random profile is an essential part of the model. This model was used for evaluation of heave. After heave analysis, shock absorber behaviour during drive was investigated. Drive conditions were defined as set of handling manoeuvres. For the drive investigation, complete multibody virtual model of racing car was used. Based on drive investigation analysis, optimal damping characteristics for each manoeuvre were found. Furthermore, each optimal characteristic was compared for different manoeuvres. Obtained results were compared. As a conclusion, compromise damping characteristic was suggested with the aim to fit the combination of all defined drive conditions. Final part of the thesis was aimed at validation of the computational model. Data measured during real drive were used as an input for this validation.
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Influence of Aerodynamics on Vehicle Handling Performance
Hejtmánek, Petr ; Kaplan, Zdeněk (referee) ; Dundálek, Radim (referee) ; Píštěk, Václav (advisor)
The main aim of this dissertation was to develop a computational tool capable of evaluating the influence of aerodynamics on the handling of a vehicle. The methodology it uses is based on the simulation of driving manoeuvres with a single-track model of a vehicle, which was composed with an emphasis on minimizing the amount of necessary input parameters. This simple model, which allows the assessment of the influence of aerodynamics on vehicle dynamic and static driveability, therefore doesn’t require large amount of input data, which makes the acquirement of relevant values easier. The computational model was validated by extensive measurements of two driving manoeuvres defined by ISO norms (step steer input and steady state cornering). As a consequence of unsatisfactory initial validation results, the differences between measurements and simulations were analysed, which led to gradual enhancements of the model with additional inputs to achieve better accuracy of simulations. The final part of the thesis deals with the comparison of influences of individual aerodynamic parameters on vehicle handling and the assessment of overall significance of aerodynamics compared to other factors which were taken into account (tires, mass properties, steering etc.). This thesis was realized in close cooperation with Škoda-Auto.
|
|
|
Vehicle Dynamics Measurement Analysis Using Mathematical Modelling
Blaťák, Ondřej ; Kledus, Robert (referee) ; Mazůrek, Ivan (referee) ; Kaplan, Zdeněk (advisor)
This doctoral thesis is focused in connection of measurement with a model in this meaning. Only relative easier measurable variables are measured on a vehicle and these variables make model inputs. This process can be improved by using dynamic filtering principles, where measured variables are used not only as model inputs, but they are used for the correction of a model motion too. We can obtain an optimal estimate of vehicle real behaviour during a manoeuvre with using this method. Linear discrete Kalman filter (dynamic filter) was used for the connection of the measurement with the mathematic model with regard to chosen model (planar linear single track model). The main task of Kalman filter is try to estimate the state of the discrete time depending process that is determined by the linear stochastic difference equation. Effective measurement system (based on CompactRIO unit) was built within the scope of this PhD thesis. This system is able to measure simultaneously a lot of quantities on the experimental vehicle. Velocity components (measured through optical correlative sensor Correvit), yaw velocity (measured through vibrating gyroscope), lateral acceleration, distance component (measured through MicrosatGPS system) are the basic measured parameters. Big attention was paid to obtain other important inputs of the mathematic model such centre of gravity position, moment of inertia, steering ratio etc. The last part of the thesis is oriented on the real connection of the measurement with the mathematic model. Formula Ford 1600 was used as the experimental car. The driving manoeuvre was arranged according to the norm ISO/WD 3888/2. Three versions of the Kalman filter were realised, which differs in the measured variables used for the mathematical model motion correction. Other possibilities, how to improve the process of state variables estimation eventually how to effective use this algorithm for vehicle parameters identification (cornering stiffness of the tires for example), are sketched in the end of the thesis.
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Tyre Temper. Meauserement on Moving Vehicle with Use of Infrared Pyromether OS100
Morávek, David ; Rasch, František (referee) ; Blaťák, Ondřej (advisor)
Bc. David Morávek Tyre temperature measurement on moving vehicle with of infrared pyrometer OS100 MT, IAE, 2008, page 70, picture 41 Problemacy of recording the temperature and tyre pressure on driven car is processed in this diploma work. Suitable measuring chain was set up. Censor holders for this type of measurement were designed and produced. Driving exams and tests are depicted in this work, too. We came to the conclusion that tyre temperature depends on lengthways and transverse acceleration of the car and also on it’s load.
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