The hotel bathroom puzzle
nevalalee.wordpress.com
nevalalee.wordpress.com
The 2018 solution to that problem would automatically involve computer vision, AI and robotics. The idea that one could construct a giant mechanical device the size of an entire bowling lane that is purpose built to lift, sweep, collect, rack, and place pins with no capacity for customization whatsoever wouldn't even occur to today's generation of engineers.
You can see it happening in some of the comments here.
It may be true if you asked software people to build it.
Ask some mechanical engineers.
See how much crap do you have to install before using some modern js framework
For some others, you need to use an Arduino to make a led blink
Or maybe the true engineers are solving other problems.
This is mainly due to the cost of maintaining something during its lifetime.
* The software can collect data about the user.
* The software can prevent repairability by the user.
* The software can enforce obsolenscence (see the absurdity of smart TVs: an expensive display that can last for 20 years bundled with a super cheap computer that is obsolete in 2).
* The software can limit the user's options, in the manufacturer's favor.
Simplicity is a means to an end. There's no point in a "simpler" solution if it's more expensive and harder to maintain.
> Or is it that writing some code to glue together off-the-shelf parts is cheaper and easier than designing and manufacturing a giant machine?
Exactly.
Good engineering is about meeting the client's needs, not about showing off your own virtuosity. Too many on HN seem to forget that.
Even if it comes out as equally difficult to maintain.
That along with lack of preview or spellcheck, scroll-away-from-post mechanics, and tiny edit boxes, are my kryptonite.
Occasionally an amusing typo emerges, though not sufficient to compensate for the pain.
Personal case in point. I've been hacking together some automated plant watering systems around my house. My initial thought was to have moisture detectors, Raspberry Pi, etc. I ended up just empirically figuring out how many seconds per day I needed to turn on the pump and that was good enough and a lot simpler/more reliable.
You're talking to software engineers here. Equating 'humanity' to us on Hacker News forgets about all of the mechanical engineers who would do a great job of racking those pins.
It didn't really affect the game, you could see or notice them. But when setting the pins, it just pulled the wires, and gently relaxed the wires till the pin was standing on it's own.
Sometimes simple does the trick :)
Personally, I prefer to bowl with lanes that have well-maintained A2s, or alternatively the newer GS-X pinsetters. I hope to eventually build a pair of lanes in my home (my motivational pipe dream), and I'd almost surely go with one of these two even versus the substantially lower upkeep requirements (mean frames between blackout) of the string pinsetters.
Long, long ago when I worked at at bowling alley, when it was busy I'd have to run down to the end of the lanes a few times a night to untangle the strings the pins were attached to.
Same guy also made an animation that gives a very detailed explanation of how the AK-47 works. The AK-47 is nothing short of breathtaking IMO. Wonderful! The guy that came up with the AK-47 was a true genius and a real master of engineering! https://youtu.be/_eQLFVpOYm4
There was talk on ha hackaday the other day about converting a windshield-wiper motor to a servo with additional components, and another user commented that the newer wiper motors are servos that have a built-in CAN bus and no mechanical linkages.
And more expensive.
It still just wipes the windows.
I can see why a programmable wiper motor is useful that scenario; send the speed and frequency as arguments and have the motor adjust on the fly.
Also, one wiper arm can be completely jammed or disabled and the other still works, where a mechanical linkage would be down for the count.
Cost will come down. Power windows used to be a luxury item too, now they're ubiquitous because the hand-crank mechanism is not only more expensive to produce, it also placed constraints on door panel styling, and having a single door design is cheaper overall.
When the hood and windshield don't have to accommodate a wiper linkage, engine packaging gets easier, allowing designs that could be safer, cheaper, more efficient, more reliable, or some combination thereof.
Don't underestimate humanity by forgetting to look outside of your bubble.
2nd where I work, I can clearly see how the 50+ yo engineers think differently than the 40+ yo, who also think differently than the rest.
So yes I don't think the 20-30 yo population would conceive of the pinsetter. I actually doubt they could even describe how the current one works. However the 50+ yo would not do anything else but that, and they could improvise one immediately.
It's a difference between being purpose built and efficient, vs need to thinker. The thinkering aimlessly stops at ~40 yo, when you figured you spent a fair amount of your life goofing around for no good reason (other than sex, money, and your social profile). At one point your realize than you might juts be able to leverage all your assets into something useful.
Okay that last bit was both utopia and off-topic, but it feels good...
For one-offs, that seems like a good tradeoff.
In 2018, it would be odd to see a problem like this where people want pins shaped exactly the same way to be set up exactly the same way and that determine success for decades and decades. If (somehow, out of context) someone asked me for such a machine, I'd immediately be asking why not a different (or random) arrangement for a tougher challenge? Or for training? What about skinnier or fatter pins to control difficulty a little?
Those things only seem strange now because we're all accustomed to bowling being played exactly the same way our entire lives. If it were invented in 2018, I don't think it would look the same.
You'd almost be irresponsible as a software engineer to have someone explain what a bowling pin-setting machine should do, and then build it to do exactly (and only) that. For anything other than "bowling, exactly as specified," you'd be over-engineering an exact-fit solution only for your competitors to build something better and more extensible (with more bowling features / challenges) in six months.
Or in less sarcastic terms, boring is an old, old game; the proof is in the pudding.
When you only consider the result of a whole pile of small but good design choices, it seems implausible. You have to consider all those steps that led up to the current state. Standing on the shoulders of giants, and all that.
That’s an overly simplistic example but that’s the point. Tell your doctor what your symptoms are, without including statements that suggest a cause, or otherwise limit the scope of the issue.
Full context for the other readers: The puegeot 206 have a known axle problem, leading to breaking up right after warranty expires: http://clubpeugeotuk.proboards.com/thread/3298/faulty-axle-o...
It can be solved by directly welding metal to the axes. Considering how popular the 206 is in India, I thouht the OP was also relating his personal experiences with having his Puegeot fixed
"Tell me what you want to do, not how you want it done."
So business thought, why bother with drilling, let's invent Modern Art Affixer, because that's what people really want to do.
(That we can vendor-lock them in this is just an added benefit.)
Then I need a screen mounted on a wall. I can't use Modern Art Affixer, and it's something not common for regular consumers to do, but fortunately there are some (appropriately more expensive) Screen Affixing services that mostly service other businesses.
Then I want to hang a DYI piece of equipment I made and I'm shit out of luck, because individuals doing DIY hardware are too small a market to justify dedicated products.
Coming back from this nightmare - the point is, what happened with the concept of technology empowering people? That is, giving them means to solve their own problems, instead of trying to sell a ready-made solution to arbitrarily specific problem? It's not that I mind very specific solutions - but without more general, empowering technology, we'd be limited to only solving specific problems that affect large enough amount of people to justify a business around it. I worry this already starts happening at the intersection of hardware and software (e.g. most IoT products can be seen as solving overly specific problems to vendor-lock people).
So big thanks to all businesses that keep assuming that what consumers really need are standard-sized drills.
When enough of these exercises in root cause analysis (which is a bad methodology) point to the same problem, and you can monopolize the solution for that singular problem, you have a massive win on your hands.
I don't often make that accusation, but the last time I did that's exactly what it turned out to be. They were trying to dive deep into the internals of C++ to find out why their debugger was hanging, and what they were asking for just didn't have an answer. They finally found that they were doing something that led to undefined behavior, and if they had asked about that instead the question would have been answered immediately.
In the end, I stopped asking questions on SO because dealing with this kind of behaviour was too tiresome. I'm glad to see I'm not the only one who thinks like that
Some tags have friendly communities that will give a dozen of pointers in the comments.
One of my first real jobs I quickly became the favorite of some folks on the engineering team. The thing was I was not experienced, I didn't know much, but I followed a simple formula to write up problems, and they liked that. I often missed some basic steps and didn't have experience, but for whatever reason they liked how I gave them information. Also when they asked a question I was very clear and honest with "I don't know" and "I'll find out".
Other smarter techs would make assumptions based on their experience, fiddle with this and then, and then present to engineering this rambling tale that was all about what they tired to fix the problem and didn't fix it.... all while missing what the problem was in the first place, when it happened, and so on.
When I attend trade shows, I often have potential customers come and ask if we sell a particular type of technology. I’ve discovered that really what they are doing is asking if we sell the think they they _think_ is the solution to what they _think_ is the problem. It’s my job to figure out what their problem _actually_ is and then figure out if we have something that can solve _that_ problem.
One has to be quite diplomatic in these situations. They certainly know more about their domain, but I know more about technologies to solve their problem. So I need to pry out more information without sounding like I think I know more about their job than they do.
I like that part of the job.
The critical points in my example were failing to properly define the problem, and to some extent failure to communicate when engaging engineering created more work, delay, and frustration.
Goes for both video and tabletop games. In general it's good to be able to articulate your "root issues" and work your analysis of the experience from there (if that's your responsibility, otherwise leave it to the people whose responsibility it is, the root issues are the only information they need).
https://jdebp.eu/FGA/problem-report-standard-litany.html
and if you don't provide that you risk to slip on a chocolate covered banana (or XY problem):
https://jdebp.eu/FGA/put-down-the-chocolate-covered-banana.h...
Curiously I also regularly got into trouble for what I trying to do, not just the how.
How to ask questions the smart way ... (by Eric Steven Raymond)
http://www.catb.org/~esr/faqs/smart-questions.html
Sometimes a subtle difference in the wording of the question may make the difference from receiving one or more helpful/useful replies and getting some snarky reply.
To me, that's hazing. There absolutely are bad questions, but the things that make them bad are rarely subtle.
>In the last question, notice the subtle but important difference between demanding “Give me an answer” and “Please help me figure out what additional diagnostics I can run to achieve enlightenment.”
This is like the solution in the article, except deals with the "opens-inwards" case instead of the "open-outwards" case, and is less fumble-y than having to attach a rope to both doors.
Now here it is with the doors shut and the wood beam between them. ||__||
Can’t open either inward until the beam moves.
View from above - open:
|\__.__/|
||_____||
Thanks.
I'd worry about someone being ill while sat/leaning-on/collapsed on the bench though meaning you cant rotate it. I guess this is an issue for any door where a body could block it being opened? At the least in a changing room cubicle these are usually open at the top so someone could climb over in an emergency.
The bench lifting is part of the system - you can't leave rubbish or water on the bench.
You could solve a safety access issue by having the bench corner removed and replaced with a breakable component; but I'd speculate the materials are such the hinges already serve that purpose and changing the corners would lead to a lot of accidental breakage.
The bench stays in place. Both locks are linked by a bar, that can be conveniently hidden under the bench. When rotating any lock, they both rotate together.
Upvoted :)
In your case you could design it such that you can’t close the door after use without unblocking the other one. Typically people would like to close the door to the bathroom after usage.
Also, there is a failure mode here. Can you think of it?
Yes, there's also the leather strap or hook (or doorknobs, ..) breaking. I hadn't considered that, oy.
If you don't want anyone to turn on the oven, cover the knob (or remove it). Same for a door handle. There's one case of something on the shelf that's earmarked for a particular purpose? Tie or tape it in place. A sign works to give reasoning, but first you have to slow down the distracted and goal-oriented person enough to read it.
Another good example of this kind of design is circuit breaker lockouts: an electrician needs to work on a particular circuit, so they turn off the breaker. To make sure that no-one turns it on and kills them while they're still working, they bar the switch in place with a physical lock that only they have the key for. Better, some models allow multiple locks to be attached (it's like a physical concurrency semaphore). Then the circuit can't be re-powered until all locks have been removed.
I've noticed a tendency for hackers to assume that practical solutions to real world problems are theoretical, and then try to pick holes in them, forgetting that if the solution is already implemented and in place, then it probably works just fine.
OTOH, one could argue that pursuing a seemingly trivial improvement to an existing solution could - by serendipity - lead to a breakthrough that actually does solve other problems as well. But I'd guess that, on balance, there's a greater payoff for spending time on something besides incremental tweaks to existing solutions. But that's just a guess...
You would be surprised to know how many nobel prize winners do that.
Regretfully to shut the light off, I needed to first close the door, re-open the door and then finally close it.
Employ a monkey to lock/unlock both doors for you. Use something like a banana for lock and an orange for unlock, keep baskets of both fruits in the bathroom. To stock the baskets get the maids to do it when they change towels.
One of my biggest lessons in “managing up”: agree on the problem, and take any suggestions for a solution seriously. Then work to make the solution you present as good or better.
The hard part being agreeing on the problem!
Sometimes, management sees the "solution", and present it as a problem that engineers then must solve. For example, competitor has brand new feature, and management asks said feature to be implemented (presumably, keeping up with the jones style). But the actual problem isn't lack of said feature, but that customers are not buying, and the only reason that's presented is a lack of said feature.
Without a lock you have no way to prevent them coming into your room when you are not there.
Still that is some great out of the box thinking.
I'd say that the likeliness really depends on whose bathroom it is. ;)
The 'similar design problems' link in this sentence points to an article about how the video game Destiny was delayed due to a story re-write. What on earth?
Yes you lose some convenience by having to be clothed while entering and exiting the bathroom. But at least you guarantee the door is always unlocked when not in use.
Yes, strictly speaking the headlined article is likely talking about door bolts not locks.
While this would be more complex, it wouldn't get in the way as much.
Each side has two locks: one that is locked when the key is missing, and one that is locked when the key is present. To give yourself privacy, you must also lock yourself in. To exit the room, you must first unlock the other door and use the key to unlock your own door.
As the diagram goes at least, if you were sitting on the toilet, and then decided to have a bath, you'd be contorting yourself over the strap.
If they open into the room then you have two giant rods that you connect together to hold them shut? Another solution but even weirder...
Is this a typo?
1) This can only be done where its feasible to connect the two doors with a rope. What if the doors are physically seperated far away from each other, or maybe even seperate entrances to a large bulding complex?
2) You can be locked inside the bathroom if someone locks the door behind you.
So i tried coming up with my own solution to solving the specified problem while also dealing with the problems with the other solution.
First off it makes sense having a system with keys and devices that are easily installed at each door. That way you deal with problem 1.
With this solution another problem arises: You can just remove a key from the room and nothing will work, so a constraint is introduced.
Specifically: It should be impossible to exit the room while carrying any of the keys, given you don’t work together with the opposite side.
So my solution is: A connected sliding lock on both sides of both doors, plus a sliding lock containing a key on both doors inside the bathroom. So one sliding lock in the apartment side and two locks the bathroom side for each door. Inside the bathroom you can only lock the opposite sides door by locking your own door first. Locking your own door with the sliding lock containing a ley gives access to the key which you insert into one of the sliding locks on the opposite side. An important feature is that you can not remove the key from the lock on the opposite side without first unlocking it and you can not unlock your own door without using the key.
So with this system it is impossible to leave with a key from the bathroom, and you also can’t lock your opponents door without locking your own door, barring your escape.
At first I thought this solution was the perfect one, but then I realised that there is nothing stopping someone from stealing the key from the opposite side by just locking the opponent door with their sliding lock, removing the key, and leaving the room.
The solution to this is that the sliding lock for eachs side key is connected to the sliding lock on the apartment side. By this I mean that when the door is locked on the apartment side, it will make the sliding lock on the bathroom side unmovable, and aldo vice versa. If you have locked the door on your side, the sliding lock will also be immovable. This way nobody can lock you inside, and you can not steal the opponents key because it is locked from its apartment side therefore blocking the use of the sliding lock with the key on the bathroom side.
So I think this solution works, even though it is somewhat complicated. So heres the user story for using the bathroom.
1. Unlock door on apartment side. 2. Lock door on bathroom side, and take key. 3. Use key to lock door on opposite side 4. Do your business 5. Unlock opposite side, and take key 6. Use key to unlock your own door, locking the key in place in he process 7. Exit the bathroom and slide the lock again.
I guess this is what you would call «over-engineering» but it was fun trying to come up with a solution!
Please tell me if I’ve missed something that would break this, I can’t come up with anything atm.
It's to prevent people casually walking into the pool in shoes and making it dirty.
They use a single piece bar that locks both doors simultaneously.
There's only one way this could work and how it's drawn has very little to do with it.
I doubt that would happen, but use something other than leather?
> What happens if the strap gets misplaced or stolen?
Replace it?
“Unlike common designs, excellent designs can circumvent the existence of “unhappy” conditions as well as the influence of other low-performance designs. Many times this requires the new design to lower its own performance and although this is not ideal, this is usually a trade-off that can help to maximize the existing conditions.”: https://uxdesign.cc/designed-degradations-ux-patterns-for-ho...
And it's not like you'll be dancing in the bathroom, so it taking up some room that otherwise won't really be used isn't as big a problem as privacy.