Analysis of rigid-body motion from cine film measurements.

Abstract A simple method is described of calculating the co-ordinates of rigid body motion from a single cine film record, provided that the linear co-ordinate along the optical axis can be found independently for scaling. In an application to the analysis of tractor overturning motion, the relative variation of this co-ordinate was minimized by using a lens of long focal length and a distant camera position. Manipulation of the axis rotation transform was simplified by a choice of axes and rotation sequence that took account of the one co-ordinate in which the body rotation was likely to exceed 90°.