Development of control concepts for improved driving dynamics of harvesting machines with large headers (eBook)

Benedikt Jung (Autor)

eBook Download: PDF

2018 | 1st ed. 2019
XI, 126 Seiten
Springer Berlin Heidelberg (Verlag)
978-3-662-57775-2 (ISBN)

Infos

This book examines the driving dynamics of harvesting machines with large harvesting heads. It looks at how to efficiently use these machines. The author explores a common problem that hinders machine performance when harvesting with very large headers. He deals with concepts for reducing the undesired effects of vehicle dynamics when using these machines.  

With the steadily increasing capacity of harvesting machines, the working widths of the harvesting heads get wider and the headers get heavier. It has become essential with these giant headers to use header height sensors and header control systems to avoid the headers from being run into the ground when encountering elevation changes in the terrain. A fundamental limitation of the viable speed of header height adjustments arises from the combination of the wider and heavier headers with soft agricultural tires. 

The current solution to find an appropriate speed of header height adjustments is to perform a header calibration whenever a new header is attached to the machine and to endow the machine operator with the capability to tweak the speed of adjustments manually. The result of an inappropriate speed of height adjustments is a reduction in overall productivity and an under-utilization of the harvesting machine. The author looks at ways to prevent this. He offers detailed modeling of the vertical dynamics including dynamic wheel loads. In addition, the book contains results from simulations and machine tests.

Dr.-Ing. Benedikt Jung studied Mechanical Engineering and Automotive Systems Engineering with a focus on Automation and Turbomachinery. Between 2014 and 2018 he was an external PhD student at the Institute of Agricultural Systems at the Technical University of Dresden. Since 2011, he works in the Research and Development department of a global manufacturer of Agricultural machinery.

Inhalt

Preface 6
Acknowledgements 7
Contents 8
Acronyms 10
1Introduction 11
1.1 Motivation 12
1.2 Self-propelled harvesting machines 13
1.3 State of the art in harvester header control 15
1.3.1 Basic system structure 15
1.3.2 Modes of header operation 16
1.3.3 Header height sensing concepts 17
1.3.4 Header height control approaches 19
1.3.5 Header height calibration procedures 21
1.4 Research objectives 22
1.5 Approach and structure of this book 22
References 23
2Vehicle dynamics modelling and model analysis 25
2.1 Modelling assumptions 27
2.1.1 Vehicle coordinate system 27
2.1.2 Degrees of freedom 27
2.1.3 Pitch centre 28
2.2 Planar vertical dynamics 29
2.3 Dynamic wheel loads 35
2.4 Propulsion system 37
2.5 Hydraulic raise/lower circuit 40
2.6 Hydro-mechanical coupling 44
2.7 Linearisation 45
2.8 Amplitude resonances, natural frequencies and damping 49
2.9 Sensitivity analysis of the natural frequencies and damping ratios 56
2.10 Summary and conclusions 59
2.11 Discussion of solution approaches 60
References 61
3Proactive vehicle oscillation suppression 63
3.1 Introduction to command shaping 64
3.2 Choice of the adaptation scheme 70
3.3 Signals and signal processing 73
3.3.1 Choice of the identification signals 73
3.3.2 Pre-filtering 78
3.4 Parametric model 79
3.4.1 Model order determination 80
3.4.2 Dead time determination 83
3.5 Derivation of the shaper parameters 87
3.6 Concept validation 88
3.6.1 Adaptation scheme validation 89
3.6.2 Command shaping validation 94
3.6.3 Test track benchmarking 96
3.7 Summary and conclusions 100
References 103
4The vehicle speed as additional actuator 105
4.1 Impact of the vehicle speed inclusion on the system’s controllability 106
4.2 Limitations of the viable range of vehicle speed changes 107
4.2.1 Acceleration effects on the human body 107
4.2.2 Limitations arising from the harvesting process 108
4.3 Enhancement of the vehicle speed control loop 109
4.3.1 The pitch rate controller 110
4.4 Concept validation 110
4.5 Summary and conclusions 113
References 115
5Key conclusion and future work 116
References 120
Appendix A Appendix 121
A.1 Recursive method of least squares 121
A.2 Validation test track: Adaptive command shaping 124
A.3 Adaptation scheme validation: Time-series data 125
A.4 Validation test track: Vehicle speed as actuator 128
A.5 Key symbols 129
References 134

Produkt-Details

• Erscheint lt. Verlag: 27.6.2018
• Reihe/Serie: Fortschritte Naturstofftechnik
• Zusatzinfo: XI, 126 p. 71 illus., 7 illus. in color.
• Verlagsort: Berlin
• Sprache: englisch
• Themenwelt: Technik ► Elektrotechnik / Energietechnik
• Themenwelt: Technik ► Maschinenbau
• Schlagworte: Command shaping • Harvester header hight control • Harvesting machine dynamics • Harvesting Techology • Identification of dynamic systems • Vehicle dynamics modeling
• ISBN-10: 3-662-57775-5 / 3662577755
• ISBN-13: 978-3-662-57775-2 / 9783662577752