Search Results

The relationship between the soil parameters measured during soil testing using the bevameter system and horizontal forces acting on a simple tillage tool were investigated. Field experiments were conducted on untilled, compacted soil and on recently tilled soil. On both soils, five sites were randomly chosen where bevameter and draft measurements were performed. The parameters measured were modulus of soil deformation, wet and dry bulk density, soil moisture content, tool operating depth, tool operating speed and horizontal draft. A statistical analysis of data indicated that a mathematical model for predicting draft should include operating depth, dry bulk density and modulus of deformation.

Understanding the Relationships between plants and soil is important in the development of methods of crop production. Although physical properties of soil conducive to plant growth can be recognized by experienced observers, many of these properties have not been defined satisfactorily in mathematical or physical terms. A method of measuring penetration resistance and energy exerted by a mechanical seedling (a steel probe simulating a seedling) as it moved upward through the soil surface under different levels of surface compaction and soil moisture was examined. Mechanical seedlings with 2.06, 3.19 and 4.65 mm tip diameters were tested at soil moisture levels of 13, 17, and 20%. The penetration rate of the mechanical seedling while moving through the soil was held constant at 10 mm/min. Results showed that the emergence energy increased directly with soil surface compaction pressure, initial soil moisture content, and mechanical seedling diameters.

A knowledge-based system for agricultural tillage equipment selection and management is presented. There are ten tillage systems suitable for corn and soybean production in Ontario. These systems manipulate the soil by different amounts resulting in varying levels of soil degradation, crop yields, and weed problems. Many factors, such as soil characteristics, climate, farm economics, and environmental impact make the selection of the most appropriate tillage practice a difficult task. Except for mouldboard plough, few farmers have experience operating and managing these tillage systems. Knowledge and information obtained from three experts is incorporated into the knowledge-based computer program to aid farmers in the selection and management of tillage systems. Selection criteria included in the program are environmental impact, management difficulty, economic return, and energy output/input ratio.

Field tests in sandy loam and clay soils were conducted with simple vertical tillage tools up to a speed of 18 ms-1 (65 km h-1) to determine the influence of soil types on the high-speed performance of tillage tools and the detailed relationship between draft and speed. A non-linear, dynamic finite element method (FEM) was used to simulate the variation in tool draft witii cutting speed. The prospects of high-speed tillage were discussed on tie basis of these experimental and analytical results.