Abstract: A fracturable barrier door for grain cars comprising a grid work removably positioned over the door which includes a horizontal member extending between jambs of the door and at least a pair of vertical members extending between the top and bottom of the door opening and being interconnected with the horizontal member. A disposable diaphram is positioned over the grid work on the inside thereof to seal off the interior of the car; and cooperating tubular means on the diaphram and on the door jambs for securing the diaphram thereto.

Abstract: A system for compensating forces acting on a rapidly moving vehicle transversely to its driving direction, such as transverse acceleration forces and yaw angle forces as well as possibly roll movements, by means of torques applied to the steering wheel, in which measured magnitudes of certain degrees of freedom which are detected as second derivatives with respect to time while driving, are combined with each other by an information converter and are converted into a torque which is transmitted in bypassing relationship to the servo-steering device and which signals by its occurrence to the driver the presence of disturbing forces and causes the driver to apply counter-forces; the servo-steering device is thereby so constructed that no torque stemming from the steerable wheels is transmitted to the steering wheel.