U.S. patent number 3,691,520 [Application Number 05/140,340] was granted by the patent office on 1972-09-12 for maneuvering command display for aircraft.
Invention is credited to Knut Lennart Nordstrom, Linkoping, SE.
United States Patent |
3,691,520 |
|
September 12, 1972 |
**Please see images for:
( Certificate of Correction ) ** |
MANEUVERING COMMAND DISPLAY FOR AIRCRAFT
Abstract
Maneuvering commands are displayed to an aircraft pilot by three
conspicuous bars on a background panel that has horizontal and
vertical axes of symmetry. The bars swing about their ends nearest
the intersection of said axes. Two bars, extending symmetrically to
opposite sides of the vertical axis signify pitch maneuvers, being
aligned with the horizontal axis when pitch is satisfactory or
inclined to it in the direction of required pitch change. The third
bar is aligned with the vertical axis when heading is satisfactory
or inclined to it in the direction of required heading change.
Inventors: |
Knut Lennart Nordstrom
(Saab-Scania Aktiebolag S-581-88), Linkoping, SE (N/A) |
Family
ID: |
20268551 |
Appl.
No.: |
05/140,340 |
Filed: |
May 5, 1971 |
Foreign Application Priority Data
|
|
|
|
|
May 11, 1970 [SE] |
|
|
6389/70 |
|
Current U.S.
Class: |
340/972; 340/978;
33/328; 340/975; 340/977 |
Current CPC
Class: |
B64G
1/66 (20130101); B64D 45/04 (20130101) |
Current International
Class: |
B64G
1/66 (20060101); B64D 45/04 (20060101); B64D
45/00 (20060101); G05d 001/08 (); B64d
043/00 () |
Field of
Search: |
;340/27R,27AT,27NA,26,25
;33/204R,204C |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Kathleen H. Claffy
Assistant Examiner: Thomas L. Kundert
Attorney, Agent or Firm: Ira Milton Jones
Claims
1. Means connectable with the output of a computing device for
providing a display of maneuver commands to a pilot of an aircraft,
which display is discernable with peripheral vision and signifies
the maneuvering required to bring the aircraft from its existing
situation to a predetermined situation, said means comprising: A.
means defining a display field having a vertical axis of symmetry
and a horizontal axis; B. means delineating a pair of straight
bars, each having an end on said horizontal axis and adjacent to
said vertical axis, said bars being swingable in unison about their
said ends between a position in which the bars are aligned with one
another along the horizontal axis to signify satisfactory vertical
movement and positions in which the bars are symmetrically oblique
to the horizontal axis to signify required changes in vertical
movement in the direction in which the bars are inclined and of a
magnitude corresponding to the amount of their inclination; and C.
means defining a third straight bar having one of its ends on said
vertical axis and adjacent to the horizontal axis, said third bar
being swingable about its said end between a position aligned with
the vertical axis, signifying a satisfactory heading, and positions
inclined to the vertical axis and signifying a required change of
heading in the direction of inclination and of a magnitude
corresponding to the amount of
2. The display means of claim 1, further characterized by: D. said
display field means comprising a panel having a dark substantially
flat surface; and E. the means defining each of said bars
comprising a rigid element of light
3. The display means of claim 1, further characterized by: D. said
display field means comprising a transparent projection screen; and
E. the means defining each of said bars comprising means for
generating and
4. The display means of claim 3, further characterized by: F. means
for causing the dashes of the rows that define said bars to move
lengthwise therealong in a direction corresponding to the sign of a
required change in forward velocity and at a rate corresponding to
the
5. A display device by which maneuvering commands are displayed to
a pilot of an aircraft, in following which he brings the aircraft
to a predetermined situation, and which display device is of the
type having a defined display screen, means defining generally
upright bar-like indicator means having one end that remains on a
vertical axis of symmetry on said screen and which swings about its
said end to denote required changes in heading by its inclination
to said vertical axis of symmetry, and other bar-like indicator
means swingable up and down to denote required changes in vertical
flight path, said display device being characterized by: A. said
upright bar-like indicator means having its said one end
substantially at a midpoint on the screen and extending generally
upwardly therefrom; B. said other bar-like indicator means
comprising a pair of generally horizontal bar-like indicator
elements, 1. each having one end that remains on a horizontal line
adjacent to said one end of the upright bar-like indicator, 2. said
ends of the bar-like indicator elements being nearer one another
and equidistant from said vertical axis of symmetry, and
3. said bar-like indicator elements being swingable in unison about
their said ends, symmetrically to said vertical axis of symmetry,
between a position of horizontal alignment signifying no required
change in vertical flight path and positions in which they are
inclined to said horizontal line and signify a required change in
vertical flight path in the direction of their inclination.
Description
This invention relates to apparatus for displaying maneuvering
commands to the pilot of an aircraft, and is concerned more
specifically with maneuvering command display means that can be
readily perceived and interpreted with the use of only peripheral
vision.
There are certain maneuvering situations in which the pilot of an
aircraft is required to shift his attention and vision rapidly from
instrument to instrument, and often, also, to include in his scan
the environment outside the aircraft. Pilots who engage in
instrument flight are aware of the fatigue that results from
shifting the eyes from one instrument to another, and focusing upon
and reading each instrument in turn. For the pilot to shift his
eyes between the instrument panel and the exterior of the aircraft
involves additional elements that induce fatigue, since this
requires major adjustments of the several eye muscles that control
convergence, focus and light adaptation; and while these
adjustments are performed almost automatically, their repetition at
the necessarily high frequency involved in some flight situations
is very fatiguing.
With these considerations in mind, it is the general object of this
invention to provide an aircraft instrument by which maneuvering
command signals can be displayed to the pilot, and which can be
readily seen with the use of only peripheral vision, so that its
signals can be perceived and interpreted even while the pilot's
central or foveal field of vision is fixed outside the aircraft and
focused at a distance or is concentrated on other instruments that
require closer examination.
A known type of maneuvering command display device that is intended
to be perceived with peripheral vision comprises rotatably mounted,
elongated cylinders each having a helical pattern around its
cylindrical surface. There is a cylinder for each of the
maneuvering axes, and each cylinder is caused to rotate in a
direction that indicates the direction of a required maneuver about
its corresponding axis and at a rate that indicates the magnitude
of the commanded maneuver. In a modified form of this known
display, two cylinders have counter-directed helical patterns, and
one is mounted concentrically within the other and is visible
therethrough. Upon rotation of the respective cylinders to signify
a required maneuver, their helical patterns cooperate to define a
square pattern which appears to move up, down, right or left, or in
vector directions therebetween, to signify the direction of
maneuver required.
With both of these prior types of display devices a command for a
change of direction is signified by movement of a pattern symbol,
and a satisfactory state of motion is denoted by the pattern
remaining stationary. Both of these display devices have the
disadvantage that their displays are not readily perceptible to
peripheral vision when the display pattern is stationery, and also
when the movement of the pattern is small.
Hence it is another object of this invention to provide a device
for displaying maneuvering commands wherein the display is one that
can be readily perceived and interpreted with the use of peripheral
vision alone, by reason of the fact that the display symbols define
a bold, simple pattern that varies in accordance with the type of
maneuver commanded, so that observation and interpretation of the
display is aided not only by the pattern and placement of the
symbol elements but also by their movement away from and back to a
defined and readily recognized neutral position as they signify the
satisfaction of maneuvering requirements.
It is also an object of this invention to provide a maneuvering
command display wherein the displayed maneuver command symbols
cooperate to define extremely simple patterns that are readily
perceptible to peripheral vision and have almost self-evident
significance, and wherein the displacement of a symbol element from
a predetermined neutral position by its direction and magnitude
respectively denotes the sense and magnitude of a required maneuver
denoted by the symbol element.
A further object of this invention is to provide maneuver command
display means of the character described whereby commands can be
given for composite maneuvers, such as simultaneous change of
vertical and lateral direction, by means of a pattern of command
symbols that is simple enough to be readily perceptible with
peripheral vision.
It is also an object of this invention to provide a display which
can be perceived with only peripheral vision and which can present
maneuvering commands by which the aircraft can be brought to a
predetermined situation that is completely defined both is space
and in time.
With these observations and objectives in mind, the manner in which
the invention achieves its purpose will be appreciated from the
following description and the accompanying drawings, which
exemplify the invention, it being understood that changes may be
made in the specific apparatus disclosed herein without departing
from the essentials of the invention set forth in the appended
claims.
The accompanying drawings illustrate several complete examples of
embodiments of the invention constructed according to the best
modes so far devised for the practical application of the
principles thereof, and in which:
FIG. 1 is a perspective view of a mechanically operating
maneuvering command display device mounted in the cockpit of an
airplane, as seen by the pilot of the airplane;
FIG. 2 is a view generally similar to FIG. 1 but illustrating a
modified embodiment of the invention comprising an electronically
operated maneuvering command display device wherein maneuvering
command signals are displayed on a transparent screen in the
pilot's normal forward field of vision;
FIGS. 3a-3e illustrate various maneuver command display patterns
obtainable with the device illustrated in FIG. 1;
FIGS. 4a-4e are views similar to FIGS. 3a-3e, respectively, but
showing the corresponding displays on a modified embodiment of the
device;
FIGS. 5a-5e are likewise views similar to FIGS. 3a-3e,
respectively, but showing the displays as they would appear on the
embodiment of the device illustrated in FIG. 2;
FIG. 6 is a schematic block diagram of the units in a maneuver
command signal system comprising a display device like that
illustrated in FIG. 1;
FIG. 7, is a view generally similar to FIG. 6 but illustrating a
display device like that of FIG. 2 together with its associated
equipment;
FIG. 8 is an enlarged front view of the command signal display
device shown in FIG. 1;
FIG. 9 is a perspective view of the display device shown in FIG. 8,
illustrating more or less diagrammatically the drive means and
motion transmitting means by which its display symbols are
actuated; and
FIGS. 10 and 11 illustrate displays of maneuver command and flight
situation information on a form of the device shown in FIG. 2.
Referring now more particularly to the accompanying drawings, the
numeral 5 designates generally an aircraft instrument panel above
which there is a windshield 6 through which the pilot can look
forwardly out of the aircraft. The maneuvering command display
device of this invention, which is designated generally by 7, is
mounted in such a location as to be in or closely adjacent to the
pilot's normal forward line of vision, so that the display that the
device provides is within the pilot's peripheral vision both when
he is looking forwardly through the windshield and when he is
looking at instruments on the panel.
The mechanically actuated display device of the embodiment of the
invention illustrated in FIG. 1 is mounted at the top center of the
instrument panel. The electronic embodiment of the display device
illustrated in FIG. 2 comprises a transparent projection screen 12'
that projects up from the center of the instrument panel so as to
be in the pilot's range of vision through the windshield.
To further facilitate observation of the display with peripheral
vision, the primary flight instruments most frequently referred to,
and which are designated by 8, are preferably arranged adjacent to
the face of the display device 7. As illustrated, a radar screen or
attitude indicator is mounted in the location 9 just below the
display device.
As indicated in FIGS. 6 and 7, the display device is connected with
the output of a computer 10 that receives inputs from various
flight and navigation devices 11, such as gyros for measuring the
attitude angles of the aircraft, airspeed, altitude and angle of
attack sensors, radio navigation systems, instrument landing
systems and the like. The inputs to the computer thus correspond in
part to a predetermined situation to which the aircraft is to be
maneuvered, and in part to the currently existing situation of the
aircraft, and the output of the computer that is fed to the display
device comprises signals that correspond to the computed
maneuvering of the aircraft required to bring it from its existing
situation to the predetermined situation.
In general, the computer output signals are translated by the
display device into a display pattern of bars that signify to the
pilot by their arrangement and movement the maneuvers that he must
accomplish to bring the aircraft to the predetermined situation and
to maintain it there.
Considering first the mechanical embodiment of the invention, the
pilot sees before him a screen or background 12 having a shape in
outline that is symmetrical to a vertical axis 14 and preferably
also to a horizontal axis 15, and on which moveable bars 16 and 17
are superimposed. Preferably the screen is black and the bars are
white, for maximum contrast and to facilitate observation with
peripheral vision.
Each of the bars 16 and 17 is mounted for pivotal motion about one
of its ends, to swing across the face of the screen, and the
pivoted ends of the bars are at or near the intersection of the
axes 14 and 15. The two bars 16 have their pivot axes on the
horizontal axis 15, and they extend symmetrically to opposite sides
of the vertical axis 14. The pivot axis of the bar 17 is on the
vertical axis, and it extends generally upwardly from the
horizontal axis. The positions of the two bars 16 denote pitching
(climb-dive) maneuvers, while the positions of the bar 17 denote
lateral (left-right) maneuvers.
FIGS. 3a-3e depict various maneuvering commands signified by the
bars 16 and 17 in the device illustrated in FIG. 1, wherein the
pivot axes of the bars 16 are spaced to opposite sides of the
vertical axis, and the generally upright bar 17 has its pivot axis
on the intersection of the axes 14 and 15. FIGS. 4a-4e
respectively, depict corresponding command signal patterns
displayed by a modified form of the FIG. 1 embodiment, wherein all
three bars have their pivot axes on the intersection of the axes 14
and 15.
When the display device signifies a satisfactory state of pitch and
lateral motion, the bars 16 are aligned with one another on the
horizontal axis 15, and the upright bar 17 is aligned with the
vertical axis 14, all as illustrated in FIGS. 3a and 4a, so that
the pattern defined by the bars has the form of an inverted T.
To signify a change in pitch direction, the bars 16 swing up or
swing down in unison, always remaining symmetrical to the vertical
axis 14. The direction in which the bars 16 are inclined to the
horizontal axis indicates the direction in which pitching motion is
to be changed and the amount of such inclination indicates the
magnitude of the required change. Thus FIGS. 3b and 4b illustrate a
command for an upward movement (e.g., from level flight to climb,
or from dive toward level flight), while FIGS. 3c and 4c illustrate
displays that command a downward movement (e.g., from level flight
to dive or from climb toward level flight). As in FIGS. 3a and 4a,
the position of the bar 17 in FIGS. 3b, 3c, 4b and 4c, aligned with
the vertical axis, denotes that the heading is satisfactory, that
is, that no lateral change in flight direction is to be made.
This displays illustrated in FIGS. 3d and 4d signify that pitching
motion is satisfactory but that a turn to the left is to be made.
FIGS. 3e and 4e illustrate patterns which command composite
maneuvers, signifying, in each case, that the aircraft is to be
given an upward change of pitch direction and is to be turned to
the right.
The bold and simple patterns produced by the display device are
readily observed with peripheral vision and can be interpreted
without the need for closer inspection of the display. Furthermore,
the swinging movements of the bars as they assume various patterns
draw attention to the need for maneuvering control motions and
facilitate perception of the patterns. Since the patterns formed by
the bars are well defined, the axes 14 and 15 need not actually be
delineated on the panel or screen 12 that the bars overlie. Note
that all displays are self-explanatory if the pilot is merely
instructed to "fly toward the needles."
As shown in FIG. 9, the mechanism by which the bars are actuated
comprises a moving coil 19 that is connected with the bars 16
through a known type of wishbone and bell crank linkage 20 by which
it actuates them in unison; and a moving coil 21 that is connected
through a parallelogram linkage 22 with the bar 17. The moving
coils 19 and 21 are of course connected with the computer 10 to
receive output signals from it.
As shown in FIGS. 8 and 9, the mechanical maneuvering command
display apparatus can be arranged to provide attitude information
in addition to command signals, by means of a horizon bar 23. In
straight and level flight the horizon bar is on the horizontal axis
15, and, in the manner of the classical artificial horizon, it
remains parallel with the actual horizon, tilting relative to the
axis 15 as the airplane rolls and moving bodily up and down
relative to said axis with changes in the pitch attitude of the
aircraft. The tilting axis of the horizon bar 23 is of course at
its center and remains on the vertical axis 14 in all positions of
its vertical displacement.
Tilting motion of the horizon bar is effected by means of a rotor
coil 25 which is connected with the center of the bar through a
shaft 26 and which can of course be slaved to an attitude gyro (not
shown). Vertical motion of the horizon bar is effected by means of
another rotor coil 27, suitably linked to the shaft 26 and which
can likewise be slaved to the attitude gyro.
Provision can also be made for a display of altitude information,
but to avoid unnecessary distraction and to obviate the need for
focusing upon the altitude display in order to perceive small
variations in it, altitude information is displayed only when the
aircraft is less than a predetermined critical distance above the
ground.
The altitude display symbol can comprise a pair of vertical bars
29, spaced a short distance to each side of the vertical axis 14
and which move vertically, in unison, during changes in altitude
within the critical range. The altitude display bars are actuated
by a rotor coil 30 which is connected with them through suitable
motion transmission means 31 and which can be slaved to an altitude
sensor (not shown) that can be either an aneroid or (preferably) a
radar altimeter.
When the altitude of the aircraft exceeds the predetermined
critical value (e.g., 500 feet), the altitude display bars will be
in an inoperative position. As the airplane descends through and
below the critical altitude the altitude bars will signify the
prevailing altitude by their vertical position. It will be
appreciated that the altitude bars can function according to any
desired scheme of movement that is reasonably self-explanatory. For
example, they can be concealed at a level beneath the visible part
of the background screen 12 when altitude of the aircraft exceeds
the critical value, and within the critical range they can signify
the altitude of the aircraft by the distance H between their
bottoms and the horizontal axis 15. As an aid to interpretation of
the altitude display, the bars can be so dimensioned that their
size represents some significant unit on the altitude display
scale, as for example each bar can have a length that corresponds
to 200 ft. on its altitude scale.
In the embodiment of the invention depicted in FIGS. 2 and 7 the
bars 16' and 17' comprising the display symbols are delineated by
light projected onto the transparent screen 12' and generated
electronically. As in the first described embodiment, various
inputs are fed to a computer 10. The output side of the computer is
connected with a maneuvering command symbol generator 33, which in
turn controls a cathode ray tube 34. The command display symbols
appear on the screen of the cathode ray tube, and are projected
onto the transparent display screen 12' by means of a mirror 35 and
collimating optics 36.
Preferably the bars 16' and 17' are discontinuous, that is, each
has the appearance of a line of dashes 38. The maneuvering command
display patterns will then appear as shown in FIGS. 5a-5e, which
respectively denote the same maneuver commands as FIGS. 3a-3e and
4a-4e.
In this case speed commands can be incorporated in the maneuvering
command display pattern by providing for movement of the dashes
that comprise the direction command bars 16' and 17' . Thus, to
denote a command to increase speed, the dashes defining the bars
can be caused to move along them in directions towards their pivot
ends (i.e., convergently along the several bars), thereby creating
an impression that the pattern is moving forward, and giving the
pilot the feeling that he is falling behind the pattern so that his
more or less automatic response will be to increase his velocity.
Conversely, when the velocity is excessive, the dashes that define
the several bars are caused to move in the direction away from the
pivoted ends of the bars, creating the impression that the pattern
is expanding or coming nearer. When forward velocity is correct for
the predetermined situation, the dashes will of course remain
stationary along the bars that they define, giving the pilot the
feeling that he is maintaining a desired fixed distance from the
pattern. The magnitude of a required speed change can be denoted by
the rate of movement of the dashes along the bars.
It will be observed that with the display presenting both
directional and velocity commands as just described, all commands
necessary to bring the aircraft to a flight situation that is
predetermined as to both space and time can be presented in the
form of a simple unitary pattern that can be perceived with the use
of peripheral vision and comprehended almost automatically.
FIGS. 10 and 11 illustrate supplemental modifications that can be
made to the embodiment of the invention illustrated in FIGS. 2 and
7, whereby quantitative information concerning the prevailing
flight situation can be displayed as a supplement to the
maneuvering command display.
FIG. 10 illustrates a supplemental situation display for the
navigation phase of a flight. The horizontal axis 15 of the display
is fixed in relation to the wings of the aircraft, as is the
vertical axis 14. However, a heading scale 39 is generated and
displayed above the heading command bar 17' , along a line which
remains parallel to the horizon, and the heading along that scale
is designated by a pointer 41 that remains on a line normal to the
horizontal scale and through the intersection of the axes 14 and
15. An altitude scale 42 is displayed to the right of the
maneuvering command symbol, along a line which remains in true
vertical. The prevailing altitude is designated by a pointer 43
adjacent to the altitude scale, on a true horizontal line through
the intersection of the reference axes 14 and 15. To the left of
the heading scale 39 and to the right of the altitude scale are
displayed lines 44 denoting principal values along a flight path
angle scale. The flight path angle is read by reference to the
point 45 at which the reference axes 14 and 15 intersect, which
point is identifiable not only by reference to the bars 16' and 17'
but also by reason of the fact that it is defined by perpendiculars
to the heading scale and altitude scale lines through the pointers
41 and 43. The flight path angle value lines 44 remain truly
horizontal.
FIG. 11 illustrates a flight situation display mode that is
particularly suitable for the landing approach phase of a flight.
In this case the reference axes 14 and 15 are fixed with respect to
the ground, so that the horizontal axis 15 remains in true
horizontal. The true horizon is indicated on the display by a
generated line 47 that coincides with the actual horizon 48 as seen
in the pilot's field of view, as illustrated in FIG. 2. The heading
scale 39 is in this case delineated along the generated horizon
line 47. The generated horizon line also serves as an index
cooperating with an altitude scale 42 to the right of the command
display, to provide an indication of altitude. In this case the
flight path angle scale is omitted.
From the foregoing description taken with the accompanying drawings
it will be apparent that this invention provides a display by which
maneuvering commands are so presented to the pilot of an aircraft
that he can readily perceive them with only peripheral vision, are
denoted by maneuvering command symbols which are so simple as to be
almost self-explanatory, so that the pilot can follow them almost
automatically, and can be accompanied by a simple display of the
existing flight situation.
Those skilled in the art will appreciate that the invention can be
embodied in forms other than as herein disclosed for purposes of
illustration.
* * * * *