Agricultural Engineering Research - English edition

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A DGPS-Based Safety System for Agricultural Machinery
(2000) Klee, Ulrich; Hofmann, Lutz
When DGPS technology for the localization and navigation of vehicles became available, investigations were initiated at the Institute of Agri- cultural Engineering and Land Improvement of the Martin-Luther Uni- versity Halle-Wittenberg in order to extend automatic tractor steering which had been developed as of the beginning of the nineties to comprise safety-relevant tasks. The goal of the first development step is the timely recognition of given field boundaries, natural obstacles, and freely chosen blocked areas, which are noticed in time during the field ride due to the combination of automatic steering with a Differential Global Positioning System (DGPS) and can warn the driver by triggering optical and/or acoustic signals before a critical position is reached. The intended hard- and software-based connection of these two different technical systems in a „safety system for agricultural machinery“, which has a modular design and works independently of the driver, is to make a contribution towards improved ergonomic process design and to create the necessary prerequisites for greater process security.
A Dual Sensor for Simultaneous Investigation of Soil Cone Index and Moisture Content
(2003) Sun, Yurui; Schulze Lammers, Peter; Damerow, Lutz
A dual sensor combining dielectric and mechanic principles was developed. The geometric structure of this sensor has been designed according to the ASAE- standard for penetrometer cones, and the sensor can provide a pair of output signals when inserted into soil. By analyzing both signals, one can determine the correlation among cone index, soil bulk density, and moisture content. Some preliminary experiments were performed in a laboratory environment, and the sensor will be ready for use in the field in the near future.
Adaptability of milking clusters to different udder formations in different milking systems
(2006) Rose, Sandra; Brunsch, Reiner; Schröter, Knut; Huschke, Wolfram; Klimetschek, Hans-Jörg
One important reason for udder damage may be the milk- ing equipment, especially wrong positioning of the milk- ing unit, leading to the teats being pulled by different forces. For this reason the German Agricultural Society has developed a test machine, making it possible to meas- ure four forces at the teats. To examine the influence of the resulting forces caused by different udder formations and differences between the milking systems, two udder formations were tested using different makes of automatic milking systems (AMS) and conventional milking systems (CMS). Wrong positioning of teat cups was ascertained in both systems. In CMS this was influenced mainly by the type of milking parlour and the type of support arms, and in AMS mainly by single tube guiding.
An Ammonia-Controlled Ventilation System for Fattening Pigs
(2001) Grotz, Walter; Rathmer, Barbara; Gronauer, Andreas; Schön, Hans
In farm animal housing, a good stall climate is the prerequisite for ani- mals and humans in the stall to stay healthy. Taking this into account, the legislator has set maximum limits for certain gaseous pollutants such as ammonia (NH3 ) in the calf- and pig husbandry decrees. At the Bavarian Research Center for Agricultural Engineering, an ammonia-controlled ventilation system with NH3 as an additional regulation variable besides the temperature was developed in cooperation with ventilation compa- nies and successfully tested in a stall for fattening pigs. Low-cost NH3 sensors, which were tested during the project at a gas dilution station in the laboratory and in practical trials in the stall, currently do not yet seem suitable for long-term, reliable use in an ammonia-controlled ven- tilation system.
Analysis of site-specific N-fertilization on-farm trials in cereals under assump-tion of spatial covariance structures
(2007) Thöle, Heinrich; Richter, Christel; Kroschewski, Bärbel; Ehlert, Detlef
The application of real-time sensors provides the possi- bility of adapting nitrogen fertilization to requirements in heterogeneous cereal crops site-specifically. Efficient and environmentally sound fertilization strategies can be de- veloped by the use of on-farm trials as a contribution to sensor-based farming. This paper assesses what agro- nomic effects can be found using the mechanical sensor "Crop-Meter" for nitrogen fertilization. On-farm trials were conducted to compare the application of uniform ni- trogen rates with sensor-based site-specifically applied rates. As an example, an approach is demonstrated taking the crop heterogeneity into account as a factor of interest in the statistical analysis, whereas heterogeneity is often treated as undesired noise factor. To include the hetero- geneity, yield data were classified by magnitude of the above-ground plant mass in order to create comparable conditions. Each class was analyzed by assuming mixed models taking into account spatial co-variance structures, which provided substantially better model fits than the classic ANOVA model. The trial considered showed that the reduction of nitrogen fertilizer in site-specific appli- cation (mean: 22 kg ha–1 N) caused no statistically sig- nificant yield differences by comparison with uniform application. Therefore, the spatial variation of nitrogen fertilizers seems a useful contribution to reducing direct cost of crop production and to decreasing environmental impacts.
Animal Health in Outside Climate Housing with Kennels for Fattening Pigs
(2001) Hornauer, Norbert; Haidn, Bernhard; Schön, Hans
For the assessment of the health status of fattening pigs in two outside climate stalls with resting kennels and a conventional warm house, their nasal flora was tested for four pathogens. Pasteurella haemolytica and Actinobacillus pleuropneumoniae could not be found. It was possible to isolate Pasteurella multocida and Bordetella bronchiseptica from ani- mals in every stall compartment. The percentage of germ carriers deve- loped non-uniformly in the systems and mostly without significant diffe- rences. A clear connection between detectable pathogens and lung dia- gnoses in the slaughterhouse could not be established. Damage to the integument (bursae auxiliares at the limbs) did not show any clear diffe- rences between the housing systems. With regard to the locomotor system, all three systems are characterized by few lame animals and prove flawless housing.
Application According to Plant Biomass : Sensor Based Distribution of Nitrogen Fertilizer, Growth Regulators, and Fungicides
(2004) Ehlert, Detlef; Dammer, Karl-Heinz; Völker, Ulrich
Recently a mechanical sensor pendulum-meter was developed for meas- uring the crop biomass density in cereal fields. It has a working width of 1 m and is central mounted in front of a tractor. The sensor has finished the stage of research and development and is now market available un- der the name "Crop-meter". To investigate the agronomic potential of the Crop-meter, the sensor was combined with a centrifugal spreader and a field sprayer for the variable rate application of nitrogen fertilizer, growth regulators and fungicides in real time. Based on farm scale strip trials, the effects regarding savings and yield response the new sensor was positive assessed.
Assessment of the Cost-Reduction Potential of Different Technology Improvements for a Competitive Biogas Production
(2003) Grundmann, Philipp
A substantial reduction of biogas production costs is necessary to reach cost-competitiveness of electricity produced from biogas using energy crops. Cost reduction opportunities are identified for several technologi- cal parameters within a sensitivity analysis. The analysed parameters are then evaluated based on theoretically achievable cost reductions. Results show that even under favourable operational, economic and political conditions, the achievement of competitive cost targets for electricity production from biogas using energy crops depends on the development of highly cost efficient methods and concepts, that substantially reduce production costs and increase market shares.
Bavarian animal welfare pilot farms - Labor input by comparison
(2007) Haidn, Bernhard; Schleicher, Thomas; Macuhová, Juliana
The aim of this working time study was to obtain basic data from all 34 monitored farms with different farm ac- tivities. Moreover, an overview of the labor management and working conditions in Bavarian livestock husband- ries was to be given to assess their national and interna- tional level. To collect labor input data, the farmers kept working diaries for 16 weeks over one or more periods (e.g. at least during one whole fattening period, or dis- tributed equally over the whole year), depending on their specialization. They were to enter all working procedures performed during this period. For seven farms the re- cording quality was evaluated as “unsatisfactory” or “in- sufficient”. Reliable data on labor input were obtained from the others. For the 12 dairy farms (18–99 cows) a labor input of 42 – 114 working hours (WH) per cow and year was ascertained. Milking, feeding, young cattle care and management required the greatest shares of working time in descending order. Only five farms do not exceed the available labor capacity. Three organic farms keeping 20–52 suckler cows had a labor input of 16–27 WH per cow and year. These are typical results for the herd sizes observed. In the piggeries the organic production method had a bearing on the labor input. Three organic farms keeping breeding sows needed 22–35 WH per sow and year, while four conventional farms had results between 10 and 14 WH per sow und year. Also in the pig fatten- ing activity the one organic farm tested differs substan- tially (3.7 WH per pig place and year) from the three conventional farms with 0.6–1.1 WH per pig place and year. In pig fattening production, the labor input is be- tween 4 and 98 % of the available work capacity. This was mostly influenced by the volume of production and the better utilization of the housing capacity after moving into a new building. Three farms with laying hens (500– 3,000 hen places) had a decreasing labor input per place und year with increasing herd size. Only 15–30 % of their available work capacity was used.
Biofilters - The Influence of Different Filter Materials on the Reduction Efficiency
(2000) Martinec, Milos; Hartung, Eberhard; Jungbluth, Thomas
The influence of five different filter materials on the reduction efficiency of biofilters has been investigated in parallel long-term measurements in a stall for fattening pigs. The greatest odour reduction (approximately 81%) was achieved with biochips and a mixture of coconut fibre and fi- bre peat as filter materials. All filter materials additionally reduce am- monia emissions by an average of about 9 - 30%. Biofilters with bio- chips caused considerably lower flow resistance and electricity con- sumption than filters with other materials. Biofilters allow odour emissions from farm animal husbandry to be re- duced by approximately 25 - 95%. Ammonia emissions also diminish to a certain extent (about 0 - 35%). However, very high operating expenses are attached to the use of biofilters if they are used properly (HARTUNG et al., 1997; HOPP, 1998; MANNEBECK, 1994). For this reason, they are used only when the minimum distance required by the VDI 3471 (1986) and VDI 3472 (1986) guidelines as well as the TA Luft (1986) (German Air Pollution Regulations) cannot be kept. The selection of the filter material provides a significant possibility to further optimize bio- filters.The present study was conducted to establish the odour reduction achieved by selected filter materials. Additionally, it was the goal of this research to examine the influence of the filter material on the reduction of the emission of NH3 , CO2 , CH4 , and N 2 O, as well as flow resistance and electricity consumption.
Biogas from Energy Crops - Results from Long-Term Lab Scale Experiments
(2003) Linke, Bernd
Biogas production from crushed rye grain and fodder sugar beets was studied in long-term lab scale experiments. For both energy crops and co- fermentation with animal waste slurry anaerobic digestion did not fail. The VS-biogas yield from mixtures of energy crops and slurry was proportional to the VS-portion of the single substrates. Application of a SBR (sequencing batch reactor) the for anaerobic digestion of fodder sugar beets at 55°C resulted in VS methane yield and methane produc- tion rate of 1.1 m3kg-1 and 3 m3m-3d-1, respectively.
Body posture analysis during visual control of fruit and vegetables at different directions and speeds of conveyor belt transport
(2007) Jakob, Martina; Geyer, Martin
Visual quality control of fruit and vegetables is a com- plex task. Reliability is important to sustain quality stan- dards. Usually the quality control is followed by or car- ried out after other mechanized processes like washing or packing. The expectations on the worker’s performance are influenced by the machine capacities. Nevertheless work place design is conservative even in modern plants; products are commonly transported on conveyor belts passing the worker from the left to the right or the other way around. Thus the man-machine-interface often be- comes a constructive shortcoming. Based on literature the superiority of a changed product transport, namely moving the products towards the worker, was to be ex- amined. A motion analysis was carried out to measure differences in the body postures as well as the amount of movements for the variations of product transport. The influence of the transport direction was very strong, re- sulting in a 100 % larger sum of motion per piece if the goods passed the worker from the right side. Most effi- cient and most comfortable proved to be the transport di- rection towards the worker.
Brown Coal reduces Slurry Emissions - Basic Investigations of the Reduction of Emissions from Slurry through Treatment with Fine-Grain Brown Coal
(2002) Hörnig, Günter; Brunsch, Reiner; Biegel, Anita; Noack, Michael
Fine-grain brown coal from the Lausitz region has been tested in the la- boratory at dosages of 3 and 5 mass-% as an alternative to swimming layers of slurry and straw. Three series of trials were carried out using slurry with dry matter contents (DM) common in practice: cattle slurry with DM = 5%, 7%, and 8.9% as well as pig slurry having a DM = 5.2% and 7.6% Together with floating slurry particles, fine-grain brown coal forms dense swimming layers, which cause a drastic reduction in odorant emission. In cattle slurry stored under undisturbed conditions, the reduc- tion amounted to approximately 70% and, after homogenizing, to 90% to 98%. In pig slurry, a 92% to 98% reduction was achieved, both before and after homogenizing. The addition of brown coal reduces the pH-value of the slurry by about 0.2 to 0.3 units and NH3 release by up to 30%. The treatment of pig slurry with fine-grain brown coal improves the con- ditions for effective solid-liquid separation into an easily conveyable liquid and a well-transportable solid with high contents of nutrients and humin. Investigations regarding the use of the large humin content of this brown coal for the long-term formation of humus remain to be carried out. In addition, questions concerning process engineering and the economic efficiency of slurry treatment with brown coal still need to be answered.
Calculation of Characteristic Curves of Helical Toothed Rotary Lobe Pumps Considering Wear
(2003) Brückner, René; Verhülsdonk, Burkhard; Türk, Meno; Zenke, Thomas
Chemosensor Systems and Odour Measurement - Current Developments in Electronic Olfactometry
(2001) Boeker, Peter
Chemosensor measuring systems termed “electronic noses” have been introduced which, very generally speaking, imitate the biological sense of smell. Even though these systems cannot primarily analyze odour char- acteristics, but rather compositions of gas mixtures, they are also used for “electronic olfactometry”. In this contribution, the background and the problems of their use and application for odour measurement are discussed. The methods which have been employed so far do not provide meaningful results. In addition, perspectives and research goals for future development are Described.
Clamping Systems and Ratio Control of Belt - or Chain CVTs
(2000) Westenthanner, Ulrich
This paper deals with new concepts for the hydraulic clamping system of continuously variable metal-chain or metal-belt drives (CVT) to improve and enlarge the basic functions and to reduce energy consumption. In addition, sufficient clamping forces must be guaranteed for the tough demands in tractors. Starting with a comparison of two actual control systems (for clamping forces and transmission ratio) which are designed for use in vehicles, an improved constant-flow clamping system is pre- sented. It meets the demands of agricultural tractors, i.e. this constant- flow system includes a ratio-shifting mode during standstill of the drive- line. Afterwards, measurement results for a new energy-saving hydraulic clamping system with pressure control are reported. It retains significant advantages of the constant-flow system. For use in tractors, it is very important to maintain immediate response of the clamping pressures even if torque increase is very high. This goal has been reached by sub- stantially redesigned torque sensors. Simulation calculations confirm the energy-saving potential and provide fundamentals for the development of the control strategies.
Comparison of Process Chains for the Supply of Bio-Fuels
(2000) Brökeland, Ruth
When planning projects for the energetic utilization of biomass, invest- ment costs as well as expenses for the processing and supply of bio-fuels must be precisely determined. The calculation of realistic prices for bio- fuels requires the consideration of complete engineering process chains, which include all work steps from the cultivation of the vegetable bio- mass to the spreading or disposal of the ashes. In feasibility studies, of- ten only simplified machinery chains or global values are considered. When the planning program HORTEB was developed, data for numerous work steps were collected and used for a comparison of different simpli- fied and complete process chains.
Comparison of Room- and Floor Heating in Piglet Houses
(2001) Büscher, Wolfgang; Kluge, Jens; Frosch, Werner
After two years of investigations, different ventilation- and heating sy- stems for piglet houses can now be evaluated comprehensively. In additi- on to the economic viability of the variants, the lying behaviour, indoor air quality, and the emission of noxious gases have been taken into ac- count. As compared with standard fans, low-energy „EC fans“ allow electricity consumption to be reduced by an average of more than 50%. With regard to heating energy, gas burners instead of hot-water floor heating with gas boilers also enabled consumption to be reduced by more than 50%. Floor heating, however, is advantageous for the lying beha- viour of young piglets and the air quality parameters.
Contributions of Dutch Agricultural Engineering Research to Precision Agriculture
(1997) Speelmann, Bert
This article resumes contributions ofthe Dutch agricultural engineering research to the development ofprecision agriculture. Dead reckoning systems are discussed for the enhancement ofpositioning accuracy. As a fundamental basic for handling georeferred data in agriculture new information models were developed. The precision of site specific fertilizer applications was examined by modeHing of spread pattems. To allow an automatic mass flow calibration for fertilizer spreaders a dynamic weighing system is described.
Cost Reductions in Natural Fibre Processing : Use of an Optimised Comb Shaker for Fibre Cleaning
(2004) Pecenka, Ralf
There is a demand for high-grade hemp and flax fibres as a raw mate- rial, not only in the automobile industry. Experience in cultivation and harvesting as well as modern processing facilities are needed for Euro- pean farmers to supply the raw fibre materials. A pilot installation has been developed at the Institute of Agricultural Engineering Bornim with which both retted and unretted hemp, flax and linseed straw can be processed. Cost-effectiveness calculations and processing trials have shown that efficient fibre processing and in particular efficient fi- bre cleaning are necessary in order to achieve an attractive straw price for the farmer.

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