LINUX flight software

So how comes that these linear indicators can't be found anymore ? All car
manufacturers on this planet ignoring human perception ?
I also had something like this on a Citroën GS...

--
Bert Willing

ASW20 "TW"


"Robert Ehrlich" a écrit dans le message de
...
André Somers wrote:
...
The "normal" instruments are very easy to
interpret (it has been shown that round dials are by far the easiest to
comprehend for the human brain: judging angles is easier than judging a
distance or reading and interpretting a figure.)
...

Not obviuous for me. Head up displays use rather vertical scales with
a moving index. I remember some Mercedes cars about 40 years ago had
also a speed indicator of this type, a colored bar filling less or more
of a vertical slot with a scale on the border. The color changed when
your speed was above the max allowed inside towns. At that time it was
purely mechanical, just a colored disc behind the slot rotating like
the usual needle around a pivot at the bottom of the slot, with a boundary
that was a spiral rather than a circle. Such an airspeed indicator in
a saiplane would probably easier to comprehend than some round dials
with more than one turn and 2 different values under the needle.
However the limitation of space to that of a standard instrument
would not allow it.

The major problem with current HUD systems is that they are projected onto a
screen screwed to the instrument panel turtledeck. Fine if you are a fighter
jock and want to keep your eye on the bandit in front of you. Also good for
IFR types who actually don't need to look out the window anyway.

What is really needed in sailplanes are head mounted displays that keep an
image hovering in front of the pilot wherever his head is. A sailplane pilot
only looking out ahead is almost as bad as one focussed on a PDA strapped to
his leg.


Ian

"tango4" wrote in message ...
The major problem with current HUD systems is that they are projected onto a
screen screwed to the instrument panel turtledeck. Fine if you are a fighter
jock and want to keep your eye on the bandit in front of you. Also good for
IFR types who actually don't need to look out the window anyway.

What is really needed in sailplanes are head mounted displays that keep an
image hovering in front of the pilot wherever his head is. A sailplane pilot
only looking out ahead is almost as bad as one focussed on a PDA strapped to
his leg.


Ian

Your description of current HUDs is somewhat misleading. HUD work by
projecting images, collimated to infinity, on a clear "combining
glass" on top of the instrument panel, in the pilots normal line of
sight. The projected symbology - attitude, heading, airspeed,
altitude, etc. is superimposed on the real world with a direct
correlation - in other words a 5 degree pitch up using the HUD scale
is a true 5 degree pitch, not a shrunk symbolic display as on a small
attitude indicator. Newer HUDs also allow projecting FLIR or LLTV
images - also collimated at infinity - on the HUD, so you have a
"virtual reality" display; cool at night. The importance of the
infinity collimation of the display is that you do not have to refocus
your eyes when looking at a HUD, you see the symbology when focused at
long distance. That is absolutely not true when "coming inside" to
read old fashioned steam gauges!

The downside is all the optics are HEAVY and power hungry, so don't
count on seeing them in a glider soon.

The newer fighters have Helmet-mounted displays that project all the
HUD symbology on their helmet visor. Still heavy, big, and power
hungry.

What I think we need for gliding is a nice big color navigation
display to replace the sectional chart that is becoming more and more
difficult to fold in our small cockpits - something that I can pull
out, look at, then put away to continue flying. Let's face it, after
awhile you can fly any glider by feel and audio vario, anyway.


Kirk

"Kirk Stant" wrote in message
om...
"tango4" wrote in message
...
The major problem with current HUD systems is that they are projected
onto a
screen screwed to the instrument panel turtledeck. Fine if you are a
fighter
jock and want to keep your eye on the bandit in front of you. Also good
for
IFR types who actually don't need to look out the window anyway.

What is really needed in sailplanes are head mounted displays that keep
an
image hovering in front of the pilot wherever his head is. A sailplane
pilot
only looking out ahead is almost as bad as one focussed on a PDA
strapped to
his leg.


Ian

Your description of current HUDs is somewhat misleading. HUD work by
projecting images, collimated to infinity, on a clear "combining
glass" on top of the instrument panel, in the pilots normal line of
sight. The projected symbology - attitude, heading, airspeed,
altitude, etc. is superimposed on the real world with a direct
correlation - in other words a 5 degree pitch up using the HUD scale
is a true 5 degree pitch, not a shrunk symbolic display as on a small
attitude indicator. Newer HUDs also allow projecting FLIR or LLTV
images - also collimated at infinity - on the HUD, so you have a
"virtual reality" display; cool at night. The importance of the
infinity collimation of the display is that you do not have to refocus
your eyes when looking at a HUD, you see the symbology when focused at
long distance. That is absolutely not true when "coming inside" to
read old fashioned steam gauges!

The downside is all the optics are HEAVY and power hungry, so don't
count on seeing them in a glider soon.

The newer fighters have Helmet-mounted displays that project all the
HUD symbology on their helmet visor. Still heavy, big, and power
hungry.

What I think we need for gliding is a nice big color navigation
display to replace the sectional chart that is becoming more and more
difficult to fold in our small cockpits - something that I can pull
out, look at, then put away to continue flying. Let's face it, after
awhile you can fly any glider by feel and audio vario, anyway.


Kirk

I have to agree with "tango4" that good glider pilots don't spend much time
looking straight ahead or "heads down" inside the cockpit.

Kirk, you are right that the current generation of HUD is heavy and power
hungry but it doesn't have to be. I once built a benchtop breadboard HUD
with semi-mirrored Mylar and plastic Frenel lenses - it worked great and
weighed less than 4 ounces including the LED light source. That little
experiment convinced me that there is a better way even though it was
technically possible.

Head mounted displays are coming fast and I think they will find a place in
glider cockpits. The latest from LeadTek
http://www.leadtek.com.tw/hmd/x_eye_1.shtml is a SVGA OLED display that
could be used with the 12V "car computers" now available. It appears that
the X-Eye would interfere with the pilots vision, however. We would need
"see-through" displays mounted on sunglass frames that give full peripheral
vision. It's nice to see an 800x600 OLED display though.

For now, I think I would find the panel mounted display a better solution,
but if sunlight readability remains a problem, eyeglass mounted displays may
be the interim solution. The neat thing about the modular x86 computers is
that the display can be replaced at will just like changing desktop
monitors.

Bill Daniels

"Bill Daniels" wrote in message
...

"Kirk Stant" wrote in message
om...
"tango4" wrote in message
...
The major problem with current HUD systems is that they are projected
onto a
screen screwed to the instrument panel turtledeck. Fine if you are a
fighter
jock and want to keep your eye on the bandit in front of you. Also
good
for
IFR types who actually don't need to look out the window anyway.

What is really needed in sailplanes are head mounted displays that
keep
an
image hovering in front of the pilot wherever his head is. A sailplane
pilot
only looking out ahead is almost as bad as one focussed on a PDA
strapped to
his leg.


Ian

Your description of current HUDs is somewhat misleading. HUD work by
projecting images, collimated to infinity, on a clear "combining
glass" on top of the instrument panel, in the pilots normal line of
sight. The projected symbology - attitude, heading, airspeed,
altitude, etc. is superimposed on the real world with a direct
correlation - in other words a 5 degree pitch up using the HUD scale
is a true 5 degree pitch, not a shrunk symbolic display as on a small
attitude indicator. Newer HUDs also allow projecting FLIR or LLTV
images - also collimated at infinity - on the HUD, so you have a
"virtual reality" display; cool at night. The importance of the
infinity collimation of the display is that you do not have to refocus
your eyes when looking at a HUD, you see the symbology when focused at
long distance. That is absolutely not true when "coming inside" to
read old fashioned steam gauges!

The downside is all the optics are HEAVY and power hungry, so don't
count on seeing them in a glider soon.

The newer fighters have Helmet-mounted displays that project all the
HUD symbology on their helmet visor. Still heavy, big, and power
hungry.

What I think we need for gliding is a nice big color navigation
display to replace the sectional chart that is becoming more and more
difficult to fold in our small cockpits - something that I can pull
out, look at, then put away to continue flying. Let's face it, after
awhile you can fly any glider by feel and audio vario, anyway.


Kirk

I have to agree with "tango4" that good glider pilots don't spend much
time
looking straight ahead or "heads down" inside the cockpit.

Kirk, you are right that the current generation of HUD is heavy and power
hungry but it doesn't have to be. I once built a benchtop breadboard HUD
with semi-mirrored Mylar and plastic Frenel lenses - it worked great and
weighed less than 4 ounces including the LED light source. That little
experiment convinced me that there is a better way even though it was
technically possible.

Head mounted displays are coming fast and I think they will find a place
in
glider cockpits. The latest from LeadTek
http://www.leadtek.com.tw/hmd/x_eye_1.shtml is a SVGA OLED display that
could be used with the 12V "car computers" now available. It appears that
the X-Eye would interfere with the pilots vision, however. We would need
"see-through" displays mounted on sunglass frames that give full
peripheral
vision. It's nice to see an 800x600 OLED display though.

For now, I think I would find the panel mounted display a better solution,
but if sunlight readability remains a problem, eyeglass mounted displays
may
be the interim solution. The neat thing about the modular x86 computers
is
that the display can be replaced at will just like changing desktop
monitors.

Bill Daniels

p.s. I just got this link by e-mail:
http://www.electronicproducts.com/Sh...ema1 .jan2002

Just imagine the comments the first time someone pitches up to the
flightline wearing one of these .....

http://iar-ira.nrc-cnrc.gc.ca/flight_1d.html

They're commercial military systems and cost about as much as Nimbus 4dM's

Ian

In article , "tango4"
writes:

Just imagine the comments the first time someone pitches up to the
flightline wearing one of these .....

http://iar-ira.nrc-cnrc.gc.ca/flight_1d.html


Let's see him close his Libelle canopy wearing that thing!

Steve

"Bill Daniels" wrote in message ...

Head mounted displays are coming fast and I think they will find a place
in glider cockpits.

Oh, I agree that a head-mounted display is the optimum solution for
exactly the reason stated - no need to look forward and refocus to
check the panel instruments. The key is images that are focused at
infinity and do not require refocusing the eyes; do the current "low
cost" displays (and emerging technologies) support that?. If the
technology develops, one could imagine an instrument setup that would
consist of a head-mounted display for airspeed, AOA, altitude, vario,
basic nav, speed to fly, thermal center, etc.; a heads-down big color
map display for siturational awareness, tactical planning, navigation,
weather (blipmaps!), and collision avoidance; an integrated radio/mode
S transponder/GPS/datalinik; and small backup airspeed, altimeter,
vario at the bottom of the panel. Controls would all be by HOSAF
(Hands On Stick And Flaps) after initial settings via windows on the
big display.

Then add usual aural cues for vario, and possibly (my wish) AOA when
the gear is down - so when landing out I could concentrate on flying
while controlling speed based on the optimum AOA tone. I loved that
in the F-4, it makes flying approaches in gusty or tight situations
really easy - much better than trying to sneak a peek at the airspeed
indicator!

Funny about all the studies that say that round dials are easier to
read than digital meters - I've read them too, and from personal
experience, I have to disagree - I end up using the digital readouts
for vario a lot more than the jumping needle, with of course audio for
trend info. And it seems the military and airlines agree - all big
glass displays and HUDs use ditigal displays, with perhaps a dial for
trend only. I think those studies were all done in pre-digital days,
when the options were a lot more limited.

Give me BIG NUMBERS anyday!

Kirk

(Kirk Stant) wrote in message

And it seems the military and airlines agree - all big
glass displays and HUDs use ditigal displays, with perhaps a dial for
trend only. I think those studies were all done in pre-digital days,
when the options were a lot more limited.

The CRT and LCD displays used in modern transport aircraft cockpits
allow the display of data in almost any format. Engineer's creativity
is usually limited by conservative certification authorities. In
almost all cases the primary flight display presents altitude and
airspeed as moving vertical tapes with a digital readout included in
the index. Glass cockpit 737 displays software provides an option to
display all instruments as conventional "steam guages". Only one 737
customer bought that option and it was to maintain commonality with
old 737's. Business jet and transport aircraft Head up Displays also
show airspeed and altitude as vertical tapes but may have a declutter
mode that removes the tapes and leaves only the precision digital
index.

Engine indications on most systems I have worked on are round dials
with a digital readout in the center. Vertical tape engine indicators
were selected by a small number of customers.

Round dials with pointers give a good indication that a parameter has
fallen outside a narrow allowed operating range but that is not
applicable to altitude and airspeed that have very large normal
operating ranges.

I have a 57mm winter altimeter and a 302. I look at the 302 altitude
first and back it up with the Winter which is harder to read.

Andy (GY)