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The Development of the New Concept of Autonomous Cranes
Kubín, Martin ; Knoflíček, Radek (referee) ; Hrabovský, Leopold (referee) ; Škopán, Miroslav (advisor)
The presented PhD thesis aims to verify the possibilities of using capacitive accelerate sensors on the crane and handling technology. Capacitive acceleration sensors of MEMS type are currently widely used in electronics, e.g. laptops and mobile phones. Using these sensors could help to automate cranes, which would eventually reduce the financial costs of material handling. Precise knowledge of their own condition and position of the machine and the load is a necessary part of autonomous manipulators. The first part of thesis deals with the exploration of scientific research in the Czech Republic and abroad. Furthermore the options of mathematical description of moving the load on the rope tow are described including solved examples. One chapter is devoted to the description of sensors that could be used in the automation of cranes. The main part is focused on description of several experiments. The experiments were conducted in a lab constructed specially for this measurement. Mainly basic simpler models are described illustrating abilities of the sensor. The last part outlines further possible progress of research in this area.
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Modelling of Load Impacts Acting on Transport and Handling Equipments with the Aim of their Optimization
Šťastný, Antonín ; Hrabovský, Leopold (referee) ; Kuľka,, Jozef (referee) ; Škopán, Miroslav (advisor)
This PhD thesis deals with employment of the state of the art methods of mathematical optimization and structural analysis in the field of load carrying steel structures of handling devices. The goal of the thesis is to compile a methodology which enables generating of optimal dimensions of conceptually designed load carrying parts of handling devices. The proposed methodology is composed of sub-methods which are successively applied to find an optimal configuration of structure according to a chosen criterion. The methodology incorporates sub-methods such as Design of Experiments, parametric finite-element modelling, the state of the art computational methods for stability assessment, mathematical approximation methods and state of the art optimization schemes based of both, heuristic and gradient principle. Recommendations from Eurocode 3 are used to introduce imperfections to the finite element model in order to perform the nonlinear buckling analysis. The practical part of this thesis is focused on optimization of welded beams. The principle of the methodology is in detail explained and demonstrated on an example of lifting spreader beam of load carrying capacity of 20 tons. The proposed methodology is practically realized by an algorithm created in Matlab software. Matlab is also utilized to implement some sub-methods including mathematical optimization schemes. Both, gradient and heuristic optimization algorithms are used for comparison and mutual verification. Structural analysis is performed by means of parametrical finite-element models which are built in the Ansys Parametric Design Language (APDL). The methodology takes into account buckling, which is inherent to thin walled structures under compressive load. The buckling analysis is performed by means of both, linear and non-linear procedures in Ansys. The output of the algorithm is an optimized configuration of the structure, which minimizes the objective function and complies with all requirements implemented in the form of design constraints.
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Interaction between Mobile Working Machines and Rolled Surfaces
Pokorný, Jan ; Hrabovský, Leopold (referee) ; Červinka, Jan (referee) ; Škopán, Miroslav (advisor)
This dissertation thesis is concerning with an interaction between mobile working machines and rolled surfaces. Machines and their constructions parts behavior were observed. There are some machines that can change state of surface. And due to these change of surface the machine is in different conditions for drive and also for works. The interaction of working machines and rolled surfaces was categorized in this work and for each category here is a methodic work flow for solution of various cases. Three examples are described in this work. Some simulating programs were used for all cases and therefore there is a methodic work flow for creating and simulating of models. Three described examples include a complex solution of hydraulic drive for vibration exciter of vibration roller, small cleaner of canalizations with aim on load case to frame of this cart. The third example describes solution of undercarriage frames of agricultural semi-trailers. This example is the most extensive chapter from this work due to including of marketing research at the beginning of development and also verification of simulated results with results from real prototype tests at the end of development of these undercarriage frames.
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Modelling of Load Impacts Acting on Transport and Handling Equipments with the Aim of their Optimization
Šťastný, Antonín ; Hrabovský, Leopold (referee) ; Kuľka,, Jozef (referee) ; Škopán, Miroslav (advisor)
This PhD thesis deals with employment of the state of the art methods of mathematical optimization and structural analysis in the field of load carrying steel structures of handling devices. The goal of the thesis is to compile a methodology which enables generating of optimal dimensions of conceptually designed load carrying parts of handling devices. The proposed methodology is composed of sub-methods which are successively applied to find an optimal configuration of structure according to a chosen criterion. The methodology incorporates sub-methods such as Design of Experiments, parametric finite-element modelling, the state of the art computational methods for stability assessment, mathematical approximation methods and state of the art optimization schemes based of both, heuristic and gradient principle. Recommendations from Eurocode 3 are used to introduce imperfections to the finite element model in order to perform the nonlinear buckling analysis. The practical part of this thesis is focused on optimization of welded beams. The principle of the methodology is in detail explained and demonstrated on an example of lifting spreader beam of load carrying capacity of 20 tons. The proposed methodology is practically realized by an algorithm created in Matlab software. Matlab is also utilized to implement some sub-methods including mathematical optimization schemes. Both, gradient and heuristic optimization algorithms are used for comparison and mutual verification. Structural analysis is performed by means of parametrical finite-element models which are built in the Ansys Parametric Design Language (APDL). The methodology takes into account buckling, which is inherent to thin walled structures under compressive load. The buckling analysis is performed by means of both, linear and non-linear procedures in Ansys. The output of the algorithm is an optimized configuration of the structure, which minimizes the objective function and complies with all requirements implemented in the form of design constraints.
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|
|
The Development of the New Concept of Autonomous Cranes
Kubín, Martin ; Knoflíček, Radek (referee) ; Hrabovský, Leopold (referee) ; Škopán, Miroslav (advisor)
The presented PhD thesis aims to verify the possibilities of using capacitive accelerate sensors on the crane and handling technology. Capacitive acceleration sensors of MEMS type are currently widely used in electronics, e.g. laptops and mobile phones. Using these sensors could help to automate cranes, which would eventually reduce the financial costs of material handling. Precise knowledge of their own condition and position of the machine and the load is a necessary part of autonomous manipulators. The first part of thesis deals with the exploration of scientific research in the Czech Republic and abroad. Furthermore the options of mathematical description of moving the load on the rope tow are described including solved examples. One chapter is devoted to the description of sensors that could be used in the automation of cranes. The main part is focused on description of several experiments. The experiments were conducted in a lab constructed specially for this measurement. Mainly basic simpler models are described illustrating abilities of the sensor. The last part outlines further possible progress of research in this area.
|
|
|
Interaction between Mobile Working Machines and Rolled Surfaces
Pokorný, Jan ; Hrabovský, Leopold (referee) ; Červinka, Jan (referee) ; Škopán, Miroslav (advisor)
This dissertation thesis is concerning with an interaction between mobile working machines and rolled surfaces. Machines and their constructions parts behavior were observed. There are some machines that can change state of surface. And due to these change of surface the machine is in different conditions for drive and also for works. The interaction of working machines and rolled surfaces was categorized in this work and for each category here is a methodic work flow for solution of various cases. Three examples are described in this work. Some simulating programs were used for all cases and therefore there is a methodic work flow for creating and simulating of models. Three described examples include a complex solution of hydraulic drive for vibration exciter of vibration roller, small cleaner of canalizations with aim on load case to frame of this cart. The third example describes solution of undercarriage frames of agricultural semi-trailers. This example is the most extensive chapter from this work due to including of marketing research at the beginning of development and also verification of simulated results with results from real prototype tests at the end of development of these undercarriage frames.
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