Development of a novel mechatronic system for mechanical weed ...

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Materials and methods plants were repeated 20 times in darkness, by daylight and with intensive artificial illumination respectively. 42 4.2 The use of integrated mechanism design and simulation in prototype development The path from an idea to a prototype can be significantly shortened by the use of integrated mechanism design and simulations. With the intensified growth of processing power and software capabilities the concept of virtual prototyping (VP) has become an appropriate alternative to conventional physical prototypes. 4.2.1 Introduction to prototypes The design process is nowadays shifting rapidly toward the use of advanced three-dimensional modelling techniques and a relatively new technology called virtual prototyping. This technique involves the creation of a comprehensive three-dimensional model capable of interacting with a virtual environment that allows for the testing of every functional aspect of a mechanism. Any mechanism can be simulated to interact directly with the same elements it will eventually encounter in its real-world environment. Up until very recently, just the last five to ten years, all prototype testing was conducted on physical prototypes that had to be manually built and tested. Although procedures for physical prototypes development have been perfected and are today quite efficient, several major drawbacks still exist, mainly because of financial, material, labour, and time demands required to complete the cycle. For any new prototyping process to be useful, it will have to continue to provide all the feedback of physical prototyping, while at the same time reducing or eliminating its drawbacks. Ideally, it will also provide additional usefulness not currently available in physical prototyping. Virtual prototyping meets all of these requirements and, as it is still a new technology, promises to continuously improve in the coming years. With the exponential growth of software and hardware capabilities at the beginning of the 21 st century, the concept of a virtual prototype has only recently
Materials and methods become a possibility. The question now is whether it is more beneficial to continue to rely on and seek to further improve physical prototyping or to switch over to a virtual prototyping centred testing process. Virtual prototyping offers many significant advantages over physical prototyping that makes it worthy of consideration and use. 4.2.2 Advantages of virtual prototyping The advantages of virtual prototyping have caused it to become widely used in the academic and industrial sectors. The most important advantages include cost savings in labour and materials, nearly immediate feedback from prototype testing, increased possibilities for design variations and shortened time from a concept to a market ready product. Many designs are unique and they entail a lot of trials to eliminate errors in order to achieve the first prototype ready for manufacturing. Time demanding development results in higher costs and delays in prototype production. The time delays are often of vital concern, because the progress in design is often halted awaiting the results of prototype testing. Often the data required from a prototype test is essential to the next design decision. Usually trained lab technicians, and not the designer, carry out the testing. This means, that the designer needs to take a lot of time to explain and describe what he exactly hopes to gain out of the test. The understanding of the experiment is potentially subject to error, and it is sometimes the case that the designer does not get all data that he would have liked from a prototype test and the experiment needs to be repeated. Also, motion experiments with a conventional physical prototype can take a lot of time and often it is hard to conduct explicit measurements. On the other hand use of virtual prototypes reduces the build-test-analyze process from weeks or even months, when all the delays are factored, to terms of minutes and hours. A simulation-ready model is simply an assembly of all the parts that have been designed, so a virtual model can be built just by defining the relations between parts and their motion constrains. The power of virtual 43
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Institut für Landtechnik der Rhein
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Development of a novel mechatronic
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Kurzfassung Entwicklung eines neuar
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Acknowledgements Acknowledgements M
Page 9 and 10: Table of contents Table of contents
Page 11 and 12: Glossary of abbreviations and symbo
Page 13 and 14: Symbol Unit Description Mmmax Nm Ma
Page 15 and 16: Symbol Unit Description Glossary of
Page 17: ωold ωout rad s -2 Latest rotatio
Page 20 and 21: Introduction The most frequently us
Page 22 and 23: Introduction application that had p
Page 24 and 25: Introduction be to go from a system
Page 26 and 27: Introduction limited and environmen
Page 28 and 29: Introduction than 40 years before g
Page 30 and 31: Introduction techniques. It is know
Page 32 and 33: Introduction Sowing and planting al
Page 34 and 35: Introduction Inter-row weeding syst
Page 36 and 37: Introduction 18 Figure 1.3 Inter-ro
Page 38 and 39: State of the art 20 Figure 2.1 a) F
Page 40 and 41: State of the art cylinder rotates a
Page 42 and 43: State of the art 1998). This device
Page 44 and 45: State of the art 26 2.2 Detection o
Page 46 and 47: State of the art The fluorescence s
Page 48 and 49: Definition of the problem and resea
Page 51 and 52: 4 Materials and methods 4.1 Detecti
Page 53 and 54: Materials and methods Figure 4.1 a)
Page 55 and 56: Materials and methods Figure 4.3 a)
Page 57 and 58: 4.1.2 Data acquisition 4.1.2.1 Hard
Page 59: 4.1.4 Test objects Materials and me
Page 63 and 64: Materials and methods environments
Page 65 and 66: Materials and methods dimensions ne
Page 67 and 68: Materials and methods (PFM). As the
Page 69 and 70: Materials and methods A command sig
Page 71 and 72: Materials and methods The drive con
Page 73: Materials and methods Another tool
Page 76 and 77: Results and discussion 58 Figure 5.
Page 82 and 83: Results and discussion objects. Acc
Page 84 and 85: Results and discussion Plant positi
Page 86 and 87: Results and discussion Plant positi
Page 88 and 89: Results and discussion 70 5.1.4 Dis
Page 92 and 93: Results and discussion Connection b
Page 94 and 95: Results and discussion 76 5.2.1 Opt
Page 96 and 97: Results and discussion xmi1 = ( RLA
Page 98 and 99: Results and discussion With the inv
Page 100 and 101: Results and discussion 82 Horizonta
Page 102 and 103: Results and discussion 84 5.2.4 Sel
Page 104 and 105: Results and discussion 86 5.2.5 Dis
Page 106 and 107: Results and discussion Conventional
Page 108 and 109: Results and discussion Since the fi
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Results and discussion To avoid con
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Results and discussion As the size
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Results and discussion 96 5.3.4 Alg
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Results and discussion 98 V = zc( t
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Results and discussion corresponds
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Results and discussion 102 5.3.6 Me
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Results and discussion hoeing accur
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Results and discussion between the
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Results and discussion distance fro
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Results and discussion Distribution
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Results and discussion cuts are ran
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Results and discussion Forward spee
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Results and discussion x [mm] Distr
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Results and discussion The experime
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6 Summary Summary Neither a mechani
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Summary The third part of the work
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7 Conclusions Conclusions The prese
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8 References References Agrios, G.
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References in California's Sacramen
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References Johnson, W C and Mullini
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References Schans, D. v. d. et al.
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List of figures List of figures Fig
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List of figures Figure 5.24 Scheme
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Plant position 9 Appendix Table 9.1
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Plant position Table 9.3 Detection
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Personal data Education About the a
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