Abstract: A tactile display device utilizes an electrorheological fluid to activate a plurality of tactile dots. A voltage is selectively produced uniformly across an electrorheological fluid flowing between a common ground electrode and a plurality of conductive dot electrodes, thereby producing an increase in the fluid's viscosity to the extent that fluid flow between the two electrodes is restricted. The flow restriction produces a build-up of electrorheological fluid in a corresponding dot actuator chamber. The resulting pressure increase in the chamber displaces an elastic diaphragm fixed to a display surface to form a lump which can be perceived by the reader as one dot in a Braille character cell. A flow regulation system provides a continually pressurized flow system and provides for free flow of the electrorheological fluid through the plurality of dot actuator chambers when they are not activated.

Abstract: A reading device for the blind for reading Braille Text directly from magnetic tape without embossing the characters on paper. A magnetic tape containing Braille Text is unloaded a page at a time into memory. The individual letters in the text are tactilly displayed using pins driven by solenoids. A position detecting "mouse" is used to control the movement from one letter to the next. The mouse is similar to those commonly used with computers. The braille display may be mounted on top of the mouse.

Abstract: Display for use on propeller driven aircraft comprised of a radially disposed row of lamps 12 embedded in the rear surface of a propeller 11. Measurements of flight data are made by conventional means and converted into digital signals (15 and 18). These digital signals are applied to graphic generators, 16 and 19, which control lamp drivers 13 which in turn control lamps 12 through slip rings 14. The lamps 12 are lit at appropriate times (determined by sync pulses 17) during each revolution of the propeller to cause the flight data in graphic form to appear to the pilot.

Abstract: Devices for vectorially summing two signals. In a first embodiment (FIG. 3) the vectorial summation is implemented by a mechanical sin/cos mechanism in which a crank 22 drives two linear potentiometers 27 and 29, 90.degree. out of phase. In a second embodiment (FIG. 6) a polarized light resolver generates the sin and cos functions. In a third embodiment (FIG. 8) a printed circuit resolver generates the sin and cos functions.