GB622312A - Improvements relating to devices for the visual simulation of motion - Google Patents

Abstract

622,312. Ground trainers for pilots. TREWEEK, K. H., and GRAY, T. C. Feb. 5, 1947, No. 3400. [Class 4] Apparatus for the visual simulation of motion, such as ground trainers for pilots and other air-crew, or amusement apparatus, comprises a light source mounted within a translucent body to project images of markings on the body on to a screen, the body being movable to cause movement of the images, and the light source being arranged for movement relative to the screen to cause movement of the images independently of movement of the translucent body. The arrangement illustrated shows a ground trainer for pilots intended to similate conditions when flying above unbroken cloud, and consists of a suitably marked translucent sphere 2 within which are mounted lights 20, Fig. 3, throwing an image on a hemispherical screen 1. The upper half 13 of the sphere is coloured blue and the lower half 14 bears a representation of cloud detail. The lamps 20 are carried by an endless chain 21 driven by an electric motor 25, the wiper contacts 27 of the lamps moving over a bus-bar of constant electrical resistance over the major portion of its length 28, the end sections 29, 30 being of graded resistance. The lamps move from right to left, and are thus gradually illuminated while passing over the end section 29, maintain uniform brilliance over the middle section 28 and fade over the other end section 30. The image on the screen 1 moves in the opposite direction, thus giving a pupil in the fuselage 3 the illusion of forward movement. Variation of air speed is simulated by varying the speed of the motor 25 by operation of a dummy throttle lever 5. The sphere 2 is mounted on gimbals carried by a frame 16 so as to be capable of rotation about axes parallel to the principal axes, movements of the dummy control column 7 and rudder 6 causing operation of electric motors geared to the sphere 2 which is thereby rotated to move the image on the screen 1 in a manner appropritate to the simulation of movement of an aircraft about its axes. Feel may be imparted to the controls by variable-fulcrum spring- loaded levers, the movement of each fulcrum being controlled by the dummy throttle lever 5, in accordance with assumed variation of air speed. The apparatus shown also comprises an epidiascope 8 with a gimbal-mounted mirror 9 by means of which an instructor may project the image of a target aircraft on the screen 1, and vary its position by operating controls 10, 11 for target and gunnery practice. To simulate the motion experienced by a reargunner, the direction of movement of the lamps 20 is reversed and the sphere 2 rotates about the vertical axis only.