TY JOUR TI Determination of kinematic constraints mathematical model of a plane-parallel motion of multi element tractor units KW tractor units KW movement KW model KW kinematic constraints JO Actual directions of scientific researches of the XXI century: theory and practice AU Antoshchenkov, R.. PY 2014 IS 2 PB FSBE Institution of Higher Education Voronezh State University of Forestry and Technologies named after G.F. Morozov