Push the Button

Crash landed B-17 and Pilot Controls

From  The UX of LEGO Interface Panels by George Cave:

Differentiating inputs 

What could cause 400 WWII pilots to raise the landing gear on their B-17 bomber just before touchdown? Catastrophic pilot error, or something more fundamental? 

It was the psychologist Alphonsis Chapanis who first suggested that the high rate of crash landings might be the fault of poor interface design. The adjacent landing gear and flap control knobs were identically shaped. The pilots never stood a chance. 

His temporary solution was to glue differently shaped strips of rubber to each switch, enabling blind operation by touch alone. This gave rise to the idea of shape coding and a system of differentiation still being followed in aircraft cockpits today.

 Via David Malki

Touch

NASA's Orion Spacecraft

I saw a story the other day about how NASA is studying manual dexterity as it pertains to operating controls in spaceships during zero gravity conditions. The story kind of implied that everything was moving to Apple iPads, which is just the kind of moronic populism that NASA has to cater to in order to maintain their funding, witness Jeff Daniels' character in The Martian.

Avid S3 Mixing Console

When it comes to audio equipment, sliders were popular with some people and maybe they still are. They got some cachet when big mixing panels used in theaters and recording studios came out from behind their curtain. Oh, cool! thought I and a bunch of other people. They might be okay in their original applications, or where space is at a premium and you need to cram in a bunch of seldom used controls into a tiny patch of panel, but for everyday audio controls they suck.
    You grab hold of a rotary control it is easy to tell how far you have turned it, even if the knob is on a radio mounted in the dashboard of car that is bouncing down a pothole filled road. Try adjusting a slider under those conditions and you can't, not with any degree of precision. You can't even adjust a slider accurately without being able to see it so you can tell how far it has move. Okay, maybe this is a personal problem. Maybe sliders don't cause you any difficulty.

    I've been having trouble with Cruise Control in my truck, and now I'm having the same trouble with the power locks in the Hyundai. The problem is that sometimes when I push the button it does what it's supposed to, and sometimes it doesn't.
    I think I figured out what the problem is. When I first got these vehicles, when I pushed the button, I would wait for it take effect before I released. It doesn't take long for that to happen, a few hundredths of a second, I imagine. As time goes by and I become habituated to the way these controls work I start releasing that button sooner. Since this shit is probably computer controlled, there isn't a direction connection between the switch and the device, everything goes through the computer, and the computer is scanning all the controls and it can only do it so fast, so if you tap the button and the computer isn't looking in that millisecond wide space of time, it will miss and it will appear that the switch is flaky. So you have to adjust. You have to hold that button down for just a little longer, long enough for the computer to register your tap.
    Problem is that sometimes your tap comes at just the right time, and even though it is really quick, it happens to fall in that window when the computer is looking and so it works fine.

    I don't like these touch screens, no tactile feedback, you have to look at them to tell where to put your fingers, and they all seem to require different amounts of pressure. Knobs and switches are what I grew up with and if they were good enough to win the great war, they ought be good enough for going to Mars.
    Mechanical switches do have problems with reliability, they're mechanical and mechanical things wear, and eventually wear out and fail. The design and construction methods employed in building our spaceships determine their life span. Sometimes they don't make it that long, but sometimes they keep going long past their expiration date. If you have your choice of a component that will wear out and one that won't, it's probably a good idea to use the one with the infinite life.

Pencils

I have a mechanical pencil that uses 0.9mm diameter lead. It works well enough, but it is not the perfect writing instrument. It has a couple of problems. The first is that the only ones I have found use a button on the side to advance the lead. This means I tend to hold the pencil in the same position, which means the tip does not get rotated, so it does not get worn evenly, which means you don't get a nicely rounded tip and the correspondingly fine control, like I do with a wooden pencil. These 0.9 mm mechanical pencils are also the really cheap ones, they do not feel like "fine writing instruments", they feel like throw aways. I think they only cost a dollar or two. On the other hand they are light weight. I have lost several (or some criminal stole them), but I have never had one break.

I have thought about using a draftsman's mechanical pencil. It has some of the advantages of both wooden and standard mechanical pencils. Like a wooden pencil, the lead is firmly gripped in place, and it is large enough not to easily break. On the downside it also needs to be sharpened, which means you also need a sharpener. Like a mechanical pencil, there is no wood going to waste, and a larger percentage of the lead can be used. Also it would require going to the store and spending ten dollars or so to buy a pencil, leads and a sharpener. And then there is the last disadvantage: there is no eraser on the other end, and that is a serious drawback.

So until someone starts selling mechanical pencils that are radially symmetrical, use a 0.9 mm lead, and have an eraser, I suppose I will be sticking with wooden pencils. And it must be readily available. I am not going to go out of my way to buy one. It will have to be at Office Depot or Fred Meyer, two big retail stores here. I do not want to spend four dollars shipping a one dollar item. I might do it for a book, but not for a pencil.