Deckard’s Elevator

This is one of those interactions that happens over a few seconds in the movie, but turns out to be quite deep—and broken—on inspection.

When Deckard enters his building’s dark, padded elevator, a flat voice announces, “Voice print identification. Your floor number, please.” He presses a dark panel, which lights up in response. He presses the 9 and 7 keys on a keypad there as he says, “Deckard. 97.” The voice immediately responds, “97. Thank you.” As the elevator moves, the interface confirms the direction of travel with gentle rising tones that correspond to the floor numbers (mod 10), which are shown rising up a 7-segment LED display. We see a green projection of the floor numbers cross Deckard’s face for a bit until, exhausted, he leans against the wall and out of the projection. When he gets to his floor, the door opens and the panel goes dark.

A need for speed

An aside: To make 97 floors in 20 seconds you have to be traveling at an average of around 47 miles per hour. That’s not unheard of today. Mashable says in a 2014 article about the world’s fastest elevators that the Hitachi elevators in Guangzhou CTF Finance Building reach up to 45 miles per hour. But including acceleration and deceleration adds to the total time, so it takes the Hitachi elevators around 43 seconds to go from the ground floor to their 95th floor. If 97 is Deckard’s floor, it’s got to be accelerating and decelerating incredibly quickly. His body doesn’t appear to be suffering those kinds of Gs, so unless they have managed to upend Newton’s basic laws of motion, something in this scene is not right. As usual, I digress.

The input control is OK

The panel design is nice and was surprising in 1982, because few people had ridden in elevators serving nearly a hundred floors. And while most in-elevator panels have a single button per floor, it would have been an overwhelming UI to present the rider of this Blade Runner complex with 100 floor buttons plus the usual open door, close door, emergency alert buttons, etc. A panel that allows combinatorial inputs reduces the number of elements that must be displayed and processed by the user, even if it slows things down, introduces cognitive overhead, and adds the need for error-handling. Such systems need a “commit” control that allows them to review, edit, and confirm the sequence, to distinguish, say, “97” from “9” and “7.” Not such an issue from the 1st floor, but a frustration from 10–96. It’s not clear those controls are part of this input.

Deckard enters 8675309, just to see what will happen.

I’m a fan of destination dispatch elevator systems that increase efficiency (with caveats) by asking riders to indicate their floor outside the elevator and letting the algorithm organize passengers into efficient groups, but that only works for banks of elevators. I get the sense Deckard’s building is a little too low-rent for such luxuries. There is just one in his building, and in-elevator controls work fine for those situations, even if they slow things down a bit.

The feedback is OK

The feedback of the floors is kind of nice in that the 7-segment numbers rise up helping to convey the direction of movement. There is also a subtle, repeating, rising series of tones that accompany the display. Most modern elevators rely on the numeracy of its passengers and their sense of equilibrium to convey this information, but sure, this is another way to do it. Also, it would be nice if the voice system would, for the visually impaired, say the floor number when the door opens.

Though the projection is dumb

I’m not sure why the little green projection of the floor numbers runs across Deckard’s face. Is it just a filmmaker’s conceit, like the genetic code that gets projected across the velociraptors head in Jurassic Park?

Pictured: Sleepy Deckard. Dumb projection.

Or is it meant to be read as diegetic, that is, that there is a projector in the elevator, spraying the floor numbers across the faces of its riders? True to the New Criticism stance of this blog, I try very hard to presume that everything is diegetic, but I just can’t make that make sense. There would be much better ways to increase the visibility of the floor numbers, and I can’t come up with any other convincing reason why this would exist.

If this was diegetic, the scene would have ended with a shredded projector.

But really, it falls apart on the interaction details

Lastly, this interaction. First, let’s give it credit where credit is due. The elevator speaks clearly and understands Deckard perfectly. No surprise, since it only needs to understand a very limited number of utterances. It’s also nice that it’s polite without being too cheery about it. People in LA circa 2019 may have had a bad day and not have time for that shit.

Where’s the wake word?

But where’s the wake word? This is a phrase like “OK elevator” or “Hey lift” that signals to the natural language system that the user is talking to the elevator and not themselves, or another person in the elevator, or even on the phone. General AI exists in the Blade Runner world, and that might allow an elevator to use contextual cues to suss this out, but there are zero clues in the film that this elevator is sentient.

There are of course other possible, implicit “wake words.” A motion detector, proximity sensor, or even weight sensor could infer that a human is present, and start the elevator listening. But with any of these implicit “wake words,” you’d still need feedback for the user to know when it was listening. And some way to help them regain attention if they got the first interaction wrong, and there would be zero affordances for this. So really, making an explicit wake word is the right way to go.

It might be that touching the number panel is the attention signal. Touch it, and the elevator listens for a few seconds. That fits in with the events in the scene, anyway. The problem with that is the redundancy. (See below.) So if the solution was pressing a button, it should just be a “talk” button rather than a numeric keypad.

It may be that the elevator is always listening, which is a little dark and would stifle any conversation in the elevator less everyone end up stuck in the basement, but this seems very error prone and unlikely.

Deckard: *Yawns* Elevator: Confirmed. Silent alarm triggered.

This issue is similar to the one discussed in Make It So Chapter 5, “Gestural Interfaces” where I discussed how a user tells a computer they are communicating to it with gestures, and when they aren’t. 

Where are the paralinguistics?

Humans provide lots of signals to one another, outside of the meaning of what is actually being said. These communication signals are called paralinguistics, and one of those that commonly appears in modern voice assistants is feedback that the system is listening. In the Google Assistant, for example, the dots let you know when it’s listening to silence and when it’s hearing your voice, providing implicit confirmation to the user that the system can hear them. (Parsing the words, understanding the meaning, and understanding the intent are separate, subsequent issues.)

Fixing this in Blade Runner could be as simple as turning on a red LED when the elevator is listening, and varying the brightness with Deckard’s volume. Maybe add chimes to indicate the starting-to-listen and no-longer-listening moments. This elevator doesn’t have anything like that, and it ought to.

Why the redundancy?

Next, why would Deckard need to push buttons to indicate “97” even while he’s saying the same number as part of the voice print? Sure, it could be that the voice print system was added later and Deckard pushes the numbers out of habit. But that bit of backworlding doesn’t buy us much.

It might be a need for redundant, confirming input. This is useful when the feedback is obscure or the stakes are high, but this is a low-stakes situation. If he enters the wrong floor, he just has to enter the correct floor. It would also be easy to imagine the elevator would understand a correction mid-ride like “Oh wait. Elevator, I need some ice. Let’s go to 93 instead.” So this is not an interaction that needs redundancy.

It’s very nice to have the discrete input as accessibility for people who cannot speak, or who have an accent that is unrecognizable to the system, or as a graceful degradation in case the speech recognition fails, but Deckard doesn’t fit any of this. He would just enter and speak his floor.

Why the personally identifiable information?

If we were designing a system and we needed, for security, a voice print, we should protect the privacy of the rider by not requiring personally identifiable information. It’s easy to imagine the spoken name being abused by stalkers and identity thieves riding the elevator with him. (And let’s not forget there is a stalker on the elevator with him in this very scene.)

This young woman, for example, would abuse the shit out of such information.

Better would be some generic phrase that stresses the parts of speech that a voiceprint system would find most effective in distinguishing people.

Tucker Saxon has written an article for VoiceIt called “Voiceprint Phrases.” In it he notes that a good voiceprint phrase needs some minimum number of non-repeating phonemes. In their case, it’s ten. A surname and a number is rarely going to provide that. “Deckard. 97,” happens to have exactly 10, but if he lived on the 2nd floor, it wouldn’t. Plus, it has that personally identifiable information, so is a non-starter.

What would be a better voiceprint phrase for this scene? Some of Saxon’s examples in the article include, “Never forget tomorrow is a new day” and “Today is a nice day to go for a walk.” While the system doesn’t care about the meaning of the phrase, the humans using it would be primed by the content, and so it would just add to the dystopia of the scene if Deckard had to utter one of these sunshine-and-rainbows phrases in an elevator that was probably an uncleaned murder scene. but I think we can do it one better.

(Hey Tucker, I would love use VoiceIt’s tools to craft a confirmed voiceprint phrase, but the signup requires that I permit your company to market to me via phone and email even though I’m just a hobbyist user, so…hard no.)

Deckard: Hi, I’m Deckard. My bank card PIN code is 3297. The combination lock to my car spells “myothercarisaspinner” and my computer password is “unicorn.” 97 please.

Here is an alternate interaction that would have solved a lot of these problems.

  • Voice print identification, please.
  • Have you considered life in the offworld colonies?
  • Confirmed. Floor?
  • 97

Which is just a punch to the gut considering Deckard is stuck here and he knows he’s stuck, and it’s salt on the wound to have to repeat fucking advertising just to get home for a drink.

So…not great

In total, this scene zooms by and the audience knows how to read it, and for that, it’s fine. (And really, it’s just a setup for the moment that happens right after the elevator door opens. No spoilers.) But on close inspection, from the perspective of modern interaction design, it needs a lot of work.


Brain Upload

Once Johnny has installed his motion detector on the door, the brain upload can begin.

3. Building it

Johnny starts by opening his briefcase and removing various components, which he connects together into the complete upload system. Some of the parts are disguised, and the whole sequence is similar to an assassin in a thriller film assembling a gun out of harmless looking pieces.


It looks strange today to see a computer system with so many external devices connected by cables. We’ve become accustomed to one piece computing devices with integrated functionality, and keyboards, mice, cameras, printers, and headphones that connect wirelessly.

Cables and other connections are not always considered as interfaces, but “all parts of a thing which enable its use” is the definition according to Chris. In the early to mid 1990s most computer user were well aware of the potential for confusion and frustration in such interfaces. A personal computer could have connections to monitor, keyboard, mouse, modem, CD drive, and joystick – and every single device would use a different type of cable. USB, while not perfect, is one of the greatest ever improvements in user interfaces. Continue reading


Biff(2015) pays for his taxi ride to the McFly household with his thumbprint. When the ride ends, a synthesized voice gives the price “one-seven-four-point-five-zero.” The taxi driver presents him with a book-sized device with the price at the top on a red 7-segment LED display. Biff presses his thumb on a reader at the bottom that glows white as it scans. When the payment is verified, the thumbprint reader and the price go dark as a sound plays like a register.


For due diligence, let me restate: multimodal biometric or multifactor authentication is more secure.


BttF_013When driving in the sky along with other flying cars that fill the skies in 2015, Doc follows a proscribed path in the sky called a “skyway.” Lanes are distinguished by floating lightposts, which the pilot keeps to his left. It all seems a little chaosy, but so does driving in Mumbai to the outsider, and it works if you know how. The other brilliance of the skyway is that suddenly flying cars make some sense systemically. Before this, I certainly thought of flying cars as personal helicopters, taking you from point to point. But of course that becomes an air traffic control nightmare. Much better to adapt a known system that puts the onus of control to the operators.

Less successful are the road signs. Continue reading

Time circuits (which interface the Flux Capacitor)

BttF_137Time traveling in the DeLorean is accomplished in three steps. In the first, he traveler turns on the “time circuits” using a rocking switch in the central console. Its use is detailed in the original Back to the Future, as below.

In the second, the traveler sets the target month, day, year, hour, and minute using a telephone keypad mounted vertically on the dashboard to the left, and pressing a button below stoplight-colored LEDs on the left, and then with an extra white status indicator below that before some kind of commit button at the bottom.

In the third, you get the DeLorean up to 88 miles per hour and flood the flux capacitor with 1.21 gigawatts of power.

Seems simple.

It’s not… Continue reading


When the Ghostbusters are called to the Sedgewick Hotel, they track a ghost called Slimer from his usual haunt on the 12th floor to a ballroom. There Ray dons a pair of asymmetrical goggles that show him information about the “psycho-kinetic energy (PKE) valences” in the area. (The Ghostbusters wiki—and of course there is such a thing—identifies these alternately as paragoggles or ectogoggles.) He uses the goggles to peek from behind a curtain to look for Slimer.


Far be it for this humble blog to try and reverse-engineer what PKE valences actually are, but let’s presume it generally means ghosts and ghost related activity. Here’s an animated gif of the display for your ghostspotting pleasure.


As he scans the room, we see a shot from his perspective. Five outputs augment the ordinary view the googles offer.

1. A plan position indicator (like what you see on a radar) sweeps around and around in the upper left hand corner, but never displays anything (even when Slimer appears.)

2. A bar graph on the left side that wavers up and down until Slimer is spotted, when it jumps to maximum. The bar graph adheres to the basic visual principle of “up means more.” The bar graph is colored with a stoplight gradient, with red at the bottom, yellow in the middle, and a bright screen-green at the top. Note that the graph builds from the bottom until it hits maximum, when its glow slides to the top to fully illuminate only the uppermost block. This is a special “max” mode that strongly draws the user’s attention.

3. There is a 7-segment red LED number display just below the graph, which you might think is a numerical version of the same data, but we only see it increment steadily from 03094 to 03051 during the first scan, then after a cutaway to Ray’s face, we see it drop to 01325 and continue to increment steadily until it hits 1333, where it remains steady and begins to blink. It hits this maximum about a half a second before the graph jumps to its max.


4. In the very lower left is a red mode label reading “KER,” which blinks until the numbers hit 01333 in the second sequence, when KER disappears and is replaced with a steadily-glowing green “MAX.”

What the heck is KER? I don’t think there’s any diegetic answer. Ker might be an extradiegetic shout-out to Rick Kerrigan, who was production supervisor for Entertainment Effects Group / Boss Film Studios for the film, but that’s just a guess. Otherwise I got nothin’. Anyone else?

5. In the lower right is a blurry light that blinks red until Slimer is spotted, when it blinks the same screen-green as the bar graph, sweep, and MAX label.

Narratively, this is a tone interface, that doesn’t add anything to the plot, and only helps us experience and understand how it is the busters do their busting. As a tone interface, making these changes would help improve believability without affecting the plot.


How to better support busting

The immediate improvements you could make to this as a “real” ghostbusting tool are fairly obvious:

  • Make the plan position indicator, you know, work.
  • Have the numbers match the graph, or, if they’re actually measuring different things, put the LED display on the other side of the view.
  • I’d change the graph color indicating no-PKE to black or dark gray. Red often connotes danger, and really, if there’s no PKE, you’re safe from the supernatural. Plus the blackbody radiation spectrum has a more physical reference and is therefore more immediate.
  • You could even lose the bar diagram—which requires looking away from the view—and replace it with a line around the view that changes color similarly. This puts the augmentation in the periphery.
  • Lose the distracting blinking red light entirely. It draws attention at a time when the Buster’s eyes need to be on the view, and it’s just duplicating information already provided in a better way by the graph.

But we can do those improvements better. In the augmented reality chapter of the book, I identified levels of awareness for these devices. The ectogoggles are an example of the simplest type, of sensor display, with the sweep giving an unfulfilled promise of the second type, location awareness. We can make even bigger improvements by considering the other levels, i.e. context and goal awareness.

Context Awareness

Context awareness implies a more sophisticated system with image recognition and display capabilities. Could the paragoggles help draw attention to where on the view the PKE is most concentrated, and how those readings are trending? Of course this wouldn’t be so important when the ghost is actually visible, but if it could lead his eyes to where the ghost is most likely going to be, it would be more useful and save him even the microseconds of an eye saccade.

A second aspect of context awareness is object or people recognition. If the goggles could recognize individual ghosts, the display be improved with some information about this particular ghost—or its category—from a database. What’s its name? What methods have failed or worked in the past to control it? Even if it doesn’t know these things, it can provide an alert that it is an UNKNOWN ENTITY, which is spooky sounding and tells the Ghostbusters to be on high alert since anything could happen.

Goal awareness

Lastly, they could be improved with goal awareness. The Ghostbusters aren’t birdwatchers. They’re there to capture that ugly spud. Can it help guide each person as to the best time to gear up the proton packs (or do it for them), where to position themselves as well as the trap, and finally when and where to fire? Certainly someone as scatterbrained as Ray could use that kind of assistance.


Federation Binoculars

When conducting reconnaissance on the bug home Planet P, Rico pauses to scan the nearby mountain crest with a pair of Federation binoculars. They feature two differently-sized objective lenses.


We get a POV for him and get to see the overlay. It includes a range-finding reticle and two 7-segment readouts in the lower corners. It looks nifty, but it’s missing some important things. Continue reading

Good morning, Korben


Korben’s alarm clock is a transparent liquid-crystal display that juts out from a panel at the foot of his bed. When it goes off, it emits a high-pitched repetitive whine. To silence it, Korben must sit up and pinch it between his fingers.

There’’s some subtle, wicked effeciveness to that deactivation. Like a regular alarm clock, the tactic is to emit some annoying sound that persists until the sleeper can rouse themselves enough to turn off the alarm. The usual problem with this tactic is that the sleeper is stupefied in his half-awakeness. If he can sleepily stop the alarm and just go back to sleep, he’ll do it. This clock dissuades sleepy flailing with its sharp-ish corners. After just a few times trying to do that and failing, the scratches on his hand will teach him. Even if the motion is memorized, the sleeper has to wake enough to target it properly and execute the simple but precise input.

The display itself shows the time in astronomical format, i.e. “02:00”, the date (Director Luc Besson‘s birthday), “18 MAR 2263″, and a temperature, 27.5° C.” Since this is quite warm, I presume this is the temperature outside.


Once Korben cancels the alarm, his apartment comes to life. Heavy-beat music begins to play and lights automatically illuminate near the fake-fish tank above the stove and in his cigarette dispenser.


All these signals combine to make it difficult for sleepy Korben to stay in bed past when awake Korben knows he should be up and moving.

Gravity (?) Scan


The first bit of human technology we see belongs to the Federation of Territories, as a spaceship engages the planet-sized object that is the Ultimate Evil. The interfaces are the screen-based systems that bridge crew use to scan the object and report back to General Staedert so he can make tactical decisions.


We see very few input mechanisms and very little interaction with the system. The screen includes a large image on the right hand side of the display and smaller detailed bits of information on the left. Inputs include

  • Rows of backlit modal pushbuttons adjacent to red LEDs
  • A few red 7-segment displays
  • An underlit trackball
  • A keyboard
  • An analog, underlit, grease-pencil plotting board.
    (Nine Inch Nails fans may be pleased to find that initialism written near the top.)

The operator of the first of these screens touches one of the pushbuttons to no results. He then scrolls the trackball downward, which scrolls the green text in the middle-left part of the screen as the graphics in the main section resolve from wireframes to photographic renderings of three stars, three planets, and the evil planet in the foreground, in blue.

FifthE-UFT008 FifthE-UFT014 FifthE-UFT010

The main challenge with the system is what the heck is being visualized? Professor Pacoli says in the beginning of the film that, “When the three planets are in eclipse, the black hole, like a door, is open.” This must refer to an unusual, trinary star system. But if that’s the case, the perspective is all wrong on screen.

Plus, the main sphere in the foreground is the evil planet, but it is resolved to a blue-tinted circle before the evil planet actually appears. So is it a measure of gravity and event horizons of the “black hole?” Then why are the others photo-real?

Where is the big red gas giant planet that the ship is currently orbiting? And where is the ship? As we know from racing game interfaces and first-person shooters, having an avatar representation of yourself is useful for orientation, and that’s missing.

And finally, why does the operator need to memorize what “Code 487” is? That places a burden on his memory that would be better used for other, more human-value things. This is something of a throw-away interface, meant only to show the high-tech nature of the Federated Territories and for an alternate view for the movie’s editor to show, but even still it presents a lot of problems.