LINUX flight software

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

Robert Ehrlich wrote in message ...
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.)
...

Also I found, on returning from hang gliding to the world of
conventional aircraft, that conventional altimeters are MUCH harder to
read than a digital output. It took me a while to get used to them
again, and I'd still much prefer digital output.

Earlier, Robert Ehrlich 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...

The assertion that angular guages are easier to read is backed up by
countless perception and human factors studies. It is also
corroborated by studies of the stimulation network pre-processing that
takes place right in the retina at the back of the eye.

Human factors texts such as McCormick's, and physiology texts on
sensation and perception deal with this topic at great length.

Thanks, and best regards to all

Bob K.

"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

Angular guages perhaps. Sweeps of 180 to 270 degrees are quite
readable, I agree. But what does the study say about altimeters with
dual needles, that rotate multiple times? How many times have you
misread the altitude or had to think hard to get it right? This has to
be the most confusing instrument to read, unless you don't really care
about knowing about that last +/- 1000 feet.

Regards,
John


(Bob Kuykendall) wrote in message . com...
Earlier, Robert Ehrlich 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...

The assertion that angular guages are easier to read is backed up by
countless perception and human factors studies. It is also
corroborated by studies of the stimulation network pre-processing that
takes place right in the retina at the back of the eye.

Human factors texts such as McCormick's, and physiology texts on
sensation and perception deal with this topic at great length.

Thanks, and best regards to all

Bob K.

"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

Thanks Bob. I'd cite Donald Norman's "The Design of Everyday Things".
Amazing what you read on R.A.S. sometimes ;-)
Best Regards, Dave

PS: Not covered in the references: You can pick up motion trends during
a scan off analog meters, but not discrete indicators (LCD). All the above
is why we (ILEC) continue to use mechanical round dials despite their being
the highest cost single component and not as reliable as the alternatives...

(Bob Kuykendall) wrote in message . com...
Earlier, Robert Ehrlich 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...

The assertion that angular guages are easier to read is backed up by
countless perception and human factors studies. It is also
corroborated by studies of the stimulation network pre-processing that
takes place right in the retina at the back of the eye.

Human factors texts such as McCormick's, and physiology texts on
sensation and perception deal with this topic at great length.

Thanks, and best regards to all

Bob K.