Talk:Head-up display/Archive 1

Archive 1

Archive 2

Copyedit round 2

I think it's done, I need a fellow copy-editor to review it.

It's done.--Anon423 (talk) 01:35, 18 October 2010 (UTC)

Confusing

In one EVS Enhanced Vision System is an industry accepted term which the FAA decided not to use because "the FAA believes would be confused with the system definition and operational concept found in 91.175(l) and (m)[15] installation, the camera is actually installed at the top of the vertical stabilizer rather than "as close as practical to the pilots eye position". Can anyone explain this? I'm copy-editing it, but can't make heads or tails of it. I've improved the rest of the article, though.

Another sentence that requires clarification is While the EVS display can greatly help, the FAA has only relaxed operating regulations[16] so an aircraft with EVS can perform a CATEGORY I approach to CATEGORY II minimums.--Anon423 (talk) 04:29, 25 July 2010 (UTC)

ad 1.

Enhanced Vision combines real world with artifical data+ terrain - ideally both should appear the same for the operator = pilot.

If camera used to impose real/IR image would be not at the same position as Pilot's eyes, there would be a difference. Tail of the plane is quite distant and higher.

It seems to me that FAA term Enhanced Flight Vision system reflect this = the flight operator has to rely on the offered image. E.g. during runway movement through this camera eye, 60 meters of a whole plane length (which has camera mounted up the tail) could be a hard miss :)

ad 2.

These differences might superimpose strict FAA regulations for a plane equipped with such a varying system on various planes.

The same example: had been the plane's pilot using the tail IR camera for landing during hard foggy conditions, camera position (+10-20m higher than pilot/undercarriage sits) could mean hard landing... with disaster at least to the landing gear.

More terrifying, the plane might be bounced off back to the air, which usually ends by land-bounce hops repeating = positive (increasing) feedback = sure dead.

https://en.wikipedia.org/wiki/Bounced_landing

Today's planes are constructed as lightweight as possible to save weight=fuel,air resistance,costs... And only a minor change in landing parameters (like uncertainity of 10m height or 10 km/h airspeed) can lead to catastrophic crash.

Like recent miracle of Russian airplane industry:

https://en.wikipedia.org/wiki/Aeroflot_Flight_1492

So FAA rules reflect this: although the plane has EVS system, it is not allowed to land under worse weather conditions than stated (= visibility of the runway within 60m limit through fog).

hope that helped. Palo.hagara (talk) 20:29, 10 August 2022 (UTC)

Focusing in cars

"while in automobiles the display is generally focused around the distance to the bumper.". Does anybody have a source for that? Or could someone explaing why manufacturers would want you to focus that close. I just tried looking out my window, and there's significant loss of focus on the ~20 m background when I focus on the ~3 m window, so it doesn't seem right to place the HUD so close. 85.224.198.207 (talk) 16:40, 13 December 2007 (UTC)

Dumb assumption: in order not to distract the eye from anything on the street. A fuzzy head-up projection is less likely to obscure something on the road.

Another problem (not mentioned in the article) with HUDs in cars is that of non-uniform backgroud brightness. A car driver may simultaneously face very dark and bright area. Like, very bright sky above and a dark tunnel ahead. Either the HUD adjusts to the sky, outshining the dark tunnel interior, or it adjusts to the tunnel, becoming so dim that the driver cannot read the speed anymore. Ot the HUD may be partially over bright and dark background, making the reading error-prone. In aircraft, this is less of a problem, since the background is more uniform. And speed-traps, curves, tunnels and pedestrains are also typically less of issue there. ;-)

Sorry, I have no sources for my information; I investiagted this stuff like 15+ years ago. --80.134.46.77 (talk) 13:44, 19 May 2008 (UTC)

Example Images

They're not great, esp not the last one. Anyone have better ones? --jazzle 02:59, 2 October 2006 (UTC)

You can lift a couple off my web site if you like. However, they're also not that good. I'll leave the decision up to you. http://www.richardfisher.com/design_examples.htm

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I'm assuming you mean the one with symthetic vision? Click on it and get the larger version it's actually pretty good (but not ideal for an entry level discussion.) The optical path for civilian HUDS is way different from military ones. For example field of view is greater, projector is overhead and not below, as well as a curved combiner rather than flat glass. Getting all of this into a package a few inches think over the pilots head is a reall challange. Brian (ZazenCID)

Head-up display != Heads up display?

Am I the only one who distinguishes between a head-up display (a display viewable without looking down) and a heads up display (a display which displays warning indications, i.e. gives you a 'heads up')?tim 13:12, 29 January 2007 (UTC)

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Your distinction is also one used within the supplier community. It's either "fly with your head up!" or "Heads up you didn't lower the gear!"  :)> Brian

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June 30 2013 Can we please promote correct spelling and the correct idiom? It is a 'head-up display' because the user can keep his/her head up while viewing the data. it's not a 'heads-up display' which would employ getting an early warning or notice. This error has proliferated, partly because of this Wikipedia article that everyone is quoting from. The title is correct, but the URL contains "heads_up" and the first line contained 'heads-up' as a synonym (I just removed that and hope it stays)... Sue Kocher, terminologist — Preceding unsigned comment added by Beautdogs (talk • contribs) 19:48, 1 July 2013 (UTC)

I have reverted it back because Wikipedia does not "promote" anything and is not a usage guide for correct speech, it is written for everyday readers per WP:NOTGUIDE. [1] and [2] show a "Heads-up display" usage. Fountains of Bryn Mawr (talk) 22:08, 1 July 2013 (UTC)

Speaking from my perspective as someone who actually worked in HUD development, standard UK usage is Head-Up, standard US usage is Heads-Up. These were well-established standard usages when I joined the GMAv HUD team at Rochester in the mid-80s. Use of Heads-Up has nothing to do with either Wikipedia or getting a heads-up.

82.11.64.250 (talk) 04:29, 13 May 2017 (UTC)

Down and Out in the Magic Kingdom Deletion

I deleted this reference from Experimental Uses. It seemed off hand and slightly irrelevant, but if anyone can show otherwise, it should go back in. It didn't seem to fit with the most of the other part of the article.John Pouliot 02:14, 16 February 2007 (UTC)

Commercially Available HUDs

I created this section from links previously in the External Links section, to indentify them as Consumer products, not necessarily unbiased informational material. I know advertising is not at all appropriate for wikipedia, but these websites are also a treasure trove of information concerning HUD technology. Is there an offical opinion on this? John Pouliot 02:14, 16 February 2007 (UTC)

Civil Aircraft Applications Discussion

I moved the technical elements of OPU discussion to the Display section, and am copyediting and wikifying Civil Aircraft Applications so far. Could ZazenCID just review these changes for accuracy? Thanks John Pouliot 02:56, 5 March 2007 (UTC)

I removed this section:

Since being introduced on HUDs, both the FPV and acceleration symbols are becoming standard on head-down displays (HDD). The actual form of the FPV symbol on a HDD is not standarized but is usually a simple aircraft drawing, such as a circle with two short angled lines, (180 ± 30 degrees) and "wings" on the ends of the descending line. Putting one of these angle lines on the horizon allows the pilot to easily fly a coordinated 30 degree turn while maintaining altitude.

because I didn't feel that it greatly contributed to HUD tech. Would it be appropriate elsewhere? John Pouliot 03:29, 5 March 2007 (UTC)

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Moving OPU to Display section. In a military HUD the projector is part of the combiner assembly. An OPU is only present in civil HUDs (and military transports) and not in tactical aircraft (where there is no overhead, only canopy) :)> Also the section is trying to discuss the HUD as a system with a few words about each of the major elements of the system. I disagree with this move. ..................................................... Removed Section - Well you can take it out, however it is a critical element of commercial HUDs. You might consider removing the first line (migration to HDD) however the discussion on the FPV itself really needs to remain. - Brian (ZazenCID)

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Update 3/5/07

Ok, I added the tactical aircraft note into the display section.

I also re-added the HDD FPV symbol information, you're completely right.

"Also the section is trying to discuss the HUD as a system with a few words about each of the major elements of the system. I disagree with this move."

What do you mean by this?

- John - John Pouliot 02:06, 6 March 2007 (UTC)

Update: Copyedited the SVS section. Truly Fascinating! John Pouliot 02:27, 6 March 2007 (UTC)

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I went back are read it and it reads fine.

I need to add material for Flight Guidance Systems as that appears to be missing from Wikipedia. On the periphery of my knowledge but I've got good stuff from the FAA that I can use as source material.

re SVS. With a side stick controller it's like flying a video game (at least in the simulator never got to fly it for real :( ) The Regulatory folks like to use a term "compelling" for these kinds of displays - that is the computer generated display can become more "real" than what is seen with the eye. One of the real challanges for the design communuity is determining that what is displayed is what is actually in the database. The whole issue of "is the database correct?" generally goes generally unanswered. (This would be a similar problem to the USS San Francisco hitting the top of a mountain while underway at high speed because the charts were not current.) A new radio tower is put up and hasn't found it's way into the charts/database yet. Pilot has a bad case of "get homeitis" tries to do a "direct in" approach because the SVS doesn't show any obstructions in their path and suddenly sees the hazard lights in their flight path. The design community can make systems safe - but only when used as intended. <sigh>

This "compelling display" concern hindered the introduction of moving map displays as there was a often expressed concern by the regulatory authorities that the pilot would go "head down" and simply fly the airplane along the route shown on the map. (IFR usually means Instrument Flight Rules but in this case would mean "I follow the Roads.") ZazenCID 22:20, 12 March 2007 (UTC)

re

Adding the Flight Guidance Systems info would be great. This article seems to be exponentially expanding. Awesome. I'm almost tempted to nominate it for Good Article status...hmmm

As for the SVS. Have there been any media-covered accidents because of its mis-use? John Pouliot 02:10, 13 March 2007 (UTC)

Sorry John - haven't been keeping up :) SVS is not approved - as yet. There are great concerns about the pilot flying SVS and not bothering to look out the window (new systems will be able to present the SVS display on either the head-up or head-down display. There is a focus on providing this as "guidance" so that IF the crew needs to deviate from a normal and approved flight path then stuff in the flight path could be brought to the crews attention before TAWS (terrain alerting and warning system - note that TAWS is related to Honeywell patents which the vigrously defend - but sometimes loose [3] It should be noted that SVS will be an external system to both HUD and HDD with these systems "just displaying the video stream." This makes life a bit easier for those of us doing "just displays" :)> Brian (ZazenCID 22:28, 31 May 2007 (UTC))

Rockwell Collins Link

I linked directly to a Collins web site. Brian — (ZazenCID 14:43, 11 June 2007 (UTC))

Update to SVS section

Added information in the SVS section related to usage of the image (actually restrictions on the use) Also added a brief note about safety analysis in one of the foot notes. Added Max-Viz and CMC to IR camera suppliers. Moved Kollsman to Commercial sites along with the new links to Max-Viz and CMC. ZazenCID 20:24, 13 April 2007 (UTC)

Removed ===Additional Applications===

• FLIR - Forward Looking InfraRed.
• Using HUD for assisting in the avodiance of runway incursions.
• The HUD designers are also working with NASA to certify a synthetic vision system, using GPS for similar terrain

Observation and scanning of the approach course for immediate obstacles in unfamiliar locations.

This was removed 5/31/07

- FLIR is the name of FLIR Systems and not used as a generic term. Also see "Enhanced Vision" earlier.

- Using HUD for taxiway guidance is an unapproved use of the system if runway visibility criteria is not met without EVS.

- The HUD is capable of showing runway edges for low visibility landings and takeoffs, however taxi way symbology would require a rule change by the regulatory agencies.

- The discussion on HUD designers also working with NASA is a duplicate of the Synthetic Vision part of this page. -Brian- (ZazenCID 22:19, 31 May 2007 (UTC))

Clarifications??? — Preceding unsigned comment added by LarryB55 (talk • contribs) 16:12, 10 November 2011 (UTC)

- At present there is NO certified application of HUD for taxiway *guidance* ('guidance' means a flight-director-like steering cue calculated within the aircraft's avionics). It's not that it is unapproved; it doesn't exist except for the occasional experimental taxi trial.

- I am of impression that HUD does not show 'runway edges'. Some HUDs present a pseudo-runway to the pilot to provide some sense of perspective and closure, but the pseudo-runway width is not related to the actual width of a particular runway, is it? -Larry- LarryB55 (talk) 16:11, 10 November 2011 (UTC)

Years late to respond to this, but added for clarity to any future editors

It's not entirely clear to me what's being discussed wrt HUDs displaying 'runway edges' but this may be a confusion of two separate issues. HUD symbology can be used to display the position of the runway during approach as a rhomboid positioned in the appropriate position on screen. GMAv for one did this with their private venture Civil HUD developed from the C-17 HUD. Matching precise runway dimensions would be possible, but there might be reasons to keep it more approximate (I was software team-lead on the C-17 HUD, but not involved with Civil HUD beyond looking through it at the symbology a handful of times). It would be technically possible to draw the runway and taxiway positions during ground movements, given a sufficiently precise aircraft location from dGPS, but I'm unclear if anyone has done this outside of trials. Unrelated to this, a HUD projecting a FLIR image (i.e. EVS) will show the runway edge if the FLIR is able to distinguish between the tarmac and the grass.

WRT 'FLIR is not a generic term'. Oh dear. Someone had better tell the entire rest of the aviation industry! It is very much a generic term in widespread daily use. FLIR Systems just happen to be one company who make FLIRs. The whole point of HUDs transitioning from purely stroke-written display symbology to using both stroke and raster driven in a single display was that the stroke-written symbology could be written during the flyback cycle of the raster-scan, while FLIR symbology could be written by the raster-scan itself. This goes back to (at least), the wide angle holographic HUD GMAv developed for the F-16C/D Block 25 in the early 80s and predates civil EVS by about a decade.82.11.64.250 (talk) 06:00, 13 May 2017 (UTC)

Areas for Improvement

The discussion of HUD 'generations' really isn't particularly good. What's currently listed as 1st generation is actually several different generations of technology/development. The technology starts with the simple beam splitter/combiner of the WWII reflector gun sights. Call that Gen 0. Then you get the initial generation of HUDs with collimated simple stroke-written symbology, Gen 1. Further developments of that adds stroke written text, still Gen 1, but a later iteration. Then in the early/mid 80s you get several new technologies introduced simultaneously in the Wide Angle Holographic HUDs. These have much bigger combiners, a significantly increased field of view, and they combine stroke-written symbology with a raster-scan presentation of the FLIR to allow the HUD to display a FLIR picture with symbology overlaid. Meanwhile the separate collimator lens became a hologram of a lens printed on the combiner. Very definitely a second or third generation of technology.

Nowhere in here do I see the term HUDWAC - HUD Weapon Aiming Computer, this was a specific term current in the 80s, but likely appearing earlier and denoting a HUD that on top of the usual flight symbology also provided more than a simple boresighted guns pipper, functioning as a form of advanced gunsight/bombsight in aircraft that didn't previously have that. So the HUD would display symbology that was specifically positioned to mark either designated targets, or the calculated impact or release points of bombs, rockets or guns, all based on various inputs fed into the HUDWAC from the rest of the aircraft systems. It seems to have fallen out of use as a term as all military HUDs came to offer that functionality, but see eg http://rochesteravionicarchives.co.uk/document-archive/brochures/hudwac-head-up-display-weapon-aiming-computer 82.11.64.250 (talk) 06:00, 13 May 2017 (UTC)

I believe the more widely used term was HUDWAS - HUD Weapon Aiming System. — Preceding unsigned comment added by 95.144.50.152 (talk) 07:58, 23 October 2020 (UTC)

Automotive section correction

List of automakers that utilize Head-Up displays was corrected and rearranged in the correct alphabetical order.

76.188.158.228 (talk) 14:48, 12 April 2008 (UTC)

Head-up display vs Heads-up display

I always thought that "heads-up display" was more correct. Should the title of this article (as well as the redirects) favor "head-up display"? CiudadanoGlobal (talk) 22:32, 22 June 2008 (UTC)

Looking through the linked references, it seems that the aviation and defense communities heavily favor "head-up display". My impression is that that was the original term, and "heads-up display" was later introduced by careless laymen, who conflated the term with the expression "heads up!", meaning "pay attention!". If you think about it, only folks like Cerberus or Janus could use a "heads-up" display. —Preceding unsigned comment added by TypoBoy (talk • contribs) 13:41, 22 August 2010 (UTC)

You are correct - the original term, 'Head-Up Display' was to differentiate between looking down into the cockpit whilst flying at high-speed at very-low altitudes. In these circumstances taking one's eyes away from looking outside the cockpit in order to look down and quickly scan one's flight instruments is dangerous. Hence the HUD allows the pilot to view his/her cockpit instruments without taking his/her eyes from looking where he/she's going - the display allows the pilot to keep his/her 'head up'.

Should we flag "heads-up display" as incorrect in the article? I've noticed that BMW uses "head-up display" correctly in their marketing material, but GM seems to use "heads-up display" universally in their marketing. (I'd hate to see this go the way of what was originally "24x7", which at some point got incorrectly transliterated by marketing folks into "24/7"; 24 divided by 7 makes no sense. Sadly, nobody corrected the marketing departments and now "24/7" is pervasive across the computer industry.) — Preceding unsigned comment added by 75.146.54.102 (talk) 10:05, 28 December 2011 (UTC)

If there is a referenced controversy we can note the controversy but Wikipedia is not a dictionary and we are not lexicologists or lexicographers. So we don't "guide" people. If a term (such as 24/7) becomes common place, and makes it into most dictionaries/reliable language guides, then that is what we use re:WP:V. Fountains of Bryn Mawr (talk) 14:35, 28 December 2011 (UTC)

Although initially developed as a sighting aid for the night fighter version of the Mosquito, the gunsight/radar system allowing the pilot to manouevre in the pitch dark without losing the target from his gunsight, and without having to look down at his artificial horizon to avoid spatial disorientation, however the HUD as we know it today really began with the Buccaneer, which was designed to fly very low at ~600 knots. For the TSR-2 it was to have been as low as 50ft at 900 knots, at which point one wonders what happens if one is unable to prevent oneself sneezing. Note: this aeroplane would actually have been flying on an autopilot incorporating automatic terrain following for much of the low-level part of the mission, so any sneezing by the pilot would probably have been irrelevant.

IIRC, one of the first US aircraft to be fitted with a HUD was the A-7 Corsair, which used a UK-manufactured one. —Preceding unsigned comment added by 86.112.86.64 (talk) 20:16, 12 October 2010 (UTC)

"Heads-up" was originally a teaching expression used to get the class's attention while they were working with their heads down on their desks, and that is probably where the confusion arose.

The original and correct wording of the aircraft instrument was as stated above, meaning the relevant cockpit instrument readings could be seen by the pilot without lowering his or her head to look down into the cockpit - all the important flight instruments could be seen whilst flying 'head up' with head looking forwards normally out of the windscreen. The normal less important instruments required a pilot to monetarily fly 'head down' when he/she looks at the conventional instruments on the dashboard/instrument panel. The importance of the HUD is that when flying at ultra low-level the pilot only has to re-focus his or her eyes to check the flight instrument readings, which is much less dangerous at high (fast jet) speeds. During this sort of low-level flying one has to concentrate one's vision on looking straight ahead out of the windscreen for possible obstacles such as electricity transmission cables and pylons that you may hit, or even worse, an aircraft coming the other way, as at these sort of flight speeds e.g., 600mph at say 50ft, they can come up on you very rapidly and with little time available to avoid hitting them. The time available can easily be as short as the time taken to look down, scan the instruments, and look up again. In that fraction of a second you've hit something that wasn't there when you last looked. — Preceding unsigned comment added by 80.7.147.13 (talk) 22:31, 11 June 2012 (UTC)

For clarity, I've noted it in the other discussion here as well, 'Head Up Display' was the standard UK usage, both industry and military, while 'Heads Up Display' was the standard US usage, both industry and military. Why the US switched to Heads rather than Head is unclear, but both usages are equally correct and have been since at least the mid-80s and probably earlier.82.11.64.250 (talk) 06:12, 13 May 2017 (UTC)