FIELD: experiments studying motions of mobile machines. SUBSTANCE: facility can be employed to evaluate stability and controllability of machines which course angle changes. Angular degree scale is marked along circumference on horizontal plotting board, element forming light and shadow boundaries proceeding from center of angular scale with outside illumination is positioned in area of vertical axis of horizontal plotting board. Light-sensitive sensors coupled to unit recording position of light-sensitive pickup with reference to light and shadow boundary are placed in correspondence with angles of this scale. Plotting board is made fast to body of mobile machine. In agreement with first variant element forming light and shadow boundaries with outside illumination comes in the form of opaque screen which one end is located in center of angular scale. In correspondence with second variant of implementation of facility element forming light and shadow boundaries with outside illumination is made in the form of screening duct with vertical slit in one wall and embraces light-sensitive sensors located inside duct. EFFECT: diminished duration of determination of course angle, expanded operational potential of facility thanks to transmission of values of course angle to recording unit for subsequent analysis and study. 2 cl, 3 dwg
