MATHEMATICAL-MODELING AND COMPUTER-AIDED-DESIGN OF PASSIVE TILLAGE TOOLS

A method of designing tillage tool shapes based on mathematical expres sions is needed A mathematical equation for the macroshape of passive tillage tools is developed The equation includes the main geometrical parameters and can be used for designing many different tillage tools. The mathematical description of tool geometry may determine how the d esign parameters influence the energy requirement and quality of opera tion. This description has the potential of achieving a quantitative a nalysis of the tillage process. A computer program has been developed to design and display selected passive fool shapes. The tool surface i s represented by a multiplicity of quadrilateral faces limited by user -selected bounding curves. The (x,y,z) face coordinates are generated by a FORTRAN program and read into AutoCAD using an AutoLISP program. The method permits a complete study of the influence of the geometrica l parameters upon the final soil condition and energy requirements, th us optimization of the tillage process may be possible.