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Have you ever hurt yourself from your own code?

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Re: Have you ever hurt yourself from your own code?

#421

Post by akiselev »

VLM wrote: post #304
akiselev wrote: post #301

Earlier quoted context omitted.

Do you know what moisture level sets it off? I didn't even think about that - it's easy to take Southern California's weather for granted. Here it's either pretty much ready from the lumberyard or you got it right off the mill's truck so it has to sit for a few days/weeks. The lobbying is off putting, yes, but at least his greedy self-interest would do some actual good instead of extracting evermore capital from ever…

Thankfully the patents are starting to expire in 2024. Nothing holds pack progress quite like the patent system. The problem with causing $300 of destruction and lost work time vs possibly saving a limb is there's no fine woodworking operation or framing carpentry operation that requires a table saw. Technically if you feel unsafe working with a table saw you can do absolutely everything very slowly and tediously wit…

Ha! You described me to a 't' and all that makes sense. As a programmer I didn't want to risk my fingers even with a SawStop cabinet so I invested the money in a Festool tracksaw and Domino instead. No crushed foot injuries yet but man I wish I had a tablesaw to cut thin pieces from stock that aren't wide enough to fully support the track.

Re: Have you ever hurt yourself from your own code?

#422

Post by devoutsalsa »

hyperhopper wrote: post #386
devoutsalsa wrote: post #89

Earlier quoted context omitted.

I wonder how long it will be before we can 3-D print a dam in place.

I mean, the novel of 3d printing is that it's just additive construction, don't we already build dams and almost all other structures that way already? A crane is just a bigger print arm :)

You have a point :)

Re: Have you ever hurt yourself from your own code?

#423

Post by robotresearcher »

xondono wrote: post #389
MauranKilom wrote: post #127

Earlier quoted context omitted.

Ouch. I'm curious what would cause the PWM output to invert under such condition? Was there a special case built in for <2% that was coded incorrectly, or did it emerge from something else?

PWM periods and on-time are implemented in the time domain in hardware, so my guess would be issues with integer algebra. Some hardware implementations are notoriously weird on edge cases. Some manufacturers built PWM modules so 0 setting on the on-time register means “no signal”, while for others it means “minimal on-time” (no signal is achieved by turning off the module). The other bad handled case is when going ab…

The uC I used did not have built in PWM. I implemented it using GPIO with excitingly bad results.

Re: Have you ever hurt yourself from your own code?

#424

Post by moralestapia »

317070 wrote: post #392

The context is building a robot for a sumo competition in university. By this time I am towards the end of my Phd, and regular strategies don't cut it anymore. We want to show off. Since many of these robots use ultrasound locators based on echolocation to find other robots, we want to eliminate those from detecting us. One of the strategies we wanted to try, was to generate sound at the right frequency ourselves, wh…

Very nice story, if only it were true.

Let's hope your PhD wasn't imaginary either, cue "science reproducibility crisis".

Re: Have you ever hurt yourself from your own code?

#425

Post by 317070 »

moralestapia wrote: post #424
317070 wrote: post #392

The context is building a robot for a sumo competition in university. By this time I am towards the end of my Phd, and regular strategies don't cut it anymore. We want to show off. Since many of these robots use ultrasound locators based on echolocation to find other robots, we want to eliminate those from detecting us. One of the strategies we wanted to try, was to generate sound at the right frequency ourselves, wh…

Very nice story, if only it were true. Let's hope your PhD wasn't imaginary either, cue "science reproducibility crisis".

Why? Because different frequencies are linearly independent and shouldn't affect eachother? That is only true for linear systems.

I am not sure what causes the other sounds to sound dampened, I figured it had something to do with how the ear works, that the sounds were physically still there.

But it is easy enough to try. Get a speaker or transducer rated for ultrasonic frequencies, and pump it with enough power that would make a real speaker sound painfully loud.

Re: Have you ever hurt yourself from your own code?

#426

Post by FabHK »

hnbad wrote: post #408
FabHK wrote: post #366

Earlier quoted context omitted.

No. It's not "take your head home", with your head (a noun) being the part standing in for the whole, namely you. Rather, "to head" is a verb that means (among other things) "to move in a specific direction". For example, an aircraft could be heading north.

Isn't "take your head home" pars pro toto given that it means "take yourself home" with the head (pars) standing in for (pro) the person (toto)?

Yes, "take your head home" would be pars pro toto, but it is not something people usually say (in particularly, that's not what GP (or GGP or whatever) said).

Re: Have you ever hurt yourself from your own code?

#427

Post by blablabla123 »

aynsof wrote: post #336
blablabla123 wrote: post #303

Earlier quoted context omitted.

I mean more the "Why don't you ..." It's quite obvious that it's rethorical but it seems so nonsensical to put this into a question while camouflaging what is really going on.

What an interesting question! As others have said, it's definitely a 'softening' of a request to make it more polite ('Go home' vs 'Would it be possible for you to go home?'). But I think there are some status games going on here, too. A subordinate would never use that phrasing with a superior. While the phrase uses conditional language to 'soften' the request, it's also an imperative (an order) that's made to look…

Thanks for the detailed answer! That makes it really understandable :)

Re: Have you ever hurt yourself from your own code?

#428

Post by softblush »

faeyanpiraat wrote: post #378
AlotOfReading wrote: post #59

Earlier quoted context omitted.

Yep. When I have to work with robots, it's from a distance and with as much safety equipment as possible. I've seen too many physical, hardware, and software failures to risk anything I care about. Hearing protection is also important. A hundred pounds or more of metal slamming into itself at high speed makes a deafening sound.

I’ve read a story somewhere, that someone trying to fix something in the toilet had to be in a position close to the toilet, then the lid accidentally fallen shut and the guy had his hearing damaged because the toilet bowl somehow concentrated the noise in one point where his head was. It’s weird how even ordinary things can be dangerously loud.

https://threadreaderapp.com/thread/979583605637877760.html

Re: Have you ever hurt yourself from your own code?

#429

Post by bradknowles »

ArchOversight wrote: post #294
akiselev wrote: post #288

Earlier quoted context omitted.

Another awesome safety system is the SawStop which uses the conductivity of skin to monitor for contact against the blade in a tablesaw. If it detects contact a small explosive charge goes off, instantly sending a block of aluminum into the path of the blade, stopping it dead. Even a serious accident like leaning with an elbow against a moving blade is likely to result in little more than the scratch from hitting a s…

The biggest problem with the saw stop is that wood when it is even slightly moist can set it off. So on a worksite if you are using lumber that hasn't had adequate time to dry the saw stop would trip even without any limbs being in danger. Each time it would destroy itself, you would have to take the saw apart and change it which would cause a work stoppage. What irks me the most is that the SawStop owner tried to cr…

Also, cutting anything that is metal or metal-coated, or otherwise conductive in any way.

You’d be surprised at the number of materials you might want to cut on a table saw that are unexpectedly conductive.

Re: Have you ever hurt yourself from your own code?

#430

Post by sowbug »

HeyLaughingBoy wrote: post #318
sowbug wrote: post #53

About seven years ago I got a bright idea to build a quadcopter. I had experience with little $25-50 drones that bumped around the house with their fragile one-inch propellers, which obviously qualified me to build and pilot something significantly bigger. Off to Aliexpress and Banggood I went. I ordered a carbon-fiber chassis, big strong motors, ESCs, 3-inch propellers, a FrSky receiver, a Devention transmitter, an…

You learn. Hopefully before someone gets hurt. I still remember an EE lab professor saying one day "get in the habit of using red wires for Power and black for Ground. That way, when you have your first accident, maybe it won't be too bad." Or a technician I used to work with who would quote his tech school instructor daily, "NO, no loose conductors on the test bench." All the nail heads on my work bench are covered…

I set my first Arduino on our washing machine, which was my platform for demos for my family. I set it right on an area with chipped paint and exposed metal.

I eventually figured out I'd shorted and destroyed the 7805 regulating the DC input to 5v. My first in-the-field electronics repair was to remove it, bodge it, and live with a USB-only Arduino. I still have that Arduino; it's a reminder of the first time I let out the magic smoke.

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