0:02

There's nothing that could possibly go wrong. Well,

0:05

at least it's a backup, right? Hello

0:08

and welcome to the Hackaday podcast. I'm

0:10

Elliott Williams. And I'm Al Williams. This

0:13

is episode 250. We'll

0:15

be talking trains, RC planes,

0:18

and EEPROMs in flames. This

0:21

week in the news, I

0:23

am off at Chaos Communication

0:26

Congress and it is absolutely

0:28

insane. 14,000 hackers

0:30

all together in the Hamburg Convention

0:32

Center, which is actually kind of

0:34

fun because the Congress used to

0:36

be here and then they had

0:38

to renovate the building. And so we had

0:40

to go somewhere else for a while. And

0:43

then there was a pandemic and now it's

0:45

back in the old building. And it's kind

0:47

of fun. It feels feels like old times.

0:49

If you're here, you already know what's going

0:51

on. But if you're not here, I've got

0:53

a link. I'll throw in the show notes

0:56

for you. But also we'll put some links

0:58

to some of the really amazing talks that

1:00

are going on. In fact, I wrote one

1:02

of them up. We'll cover that in a

1:04

minute. The really nice thing about

1:06

the CCC is that they have video of

1:08

the talks up as soon as the next

1:10

day. So if you're not here, you can

1:13

also follow along by heading over to the

1:15

website and checking out anything that looks interesting

1:17

to you. I don't know. I

1:19

looked through, there's at least 15, maybe 20

1:22

talks I want to go see. And I've

1:24

managed to see three so far. But

1:27

it's always like this when you go

1:29

to conventions. You can never see as

1:31

much as you wish you could. On

1:33

the other hand, I was able to

1:35

get us a CCC related. What's

1:37

that sound? This is a journey into sound. What's that

1:39

sound? What's that sound? So

1:42

you want to give it a listen?

2:00

I was heading for something solenoid

2:02

related at the beginning but the

2:04

end didn't make me think that's

2:07

correct So I don't know.

2:09

I'm just gonna take a random stab and

2:11

say it's a paper tape punch, but that's

2:13

not right I'll give you one hint and

2:15

that is that there are two different versions

2:18

of the same thing so

2:20

those were two like distinct sounds from

2:22

two different kinds of a Blank

2:25

I'll tune in next week. That

2:28

sounds good. I'll probably tell you

2:30

before next week But

2:32

if you're listening at home and have a good

2:34

guess as to what these things are head on

2:36

over to hackaday.com Slash podcast fill

2:39

in your best guess give us your handle

2:41

and we'll see who guesses it right next

2:43

week All right. So with that let's

2:45

head on off to the hacks I'd

2:47

like to start off with an amazing

2:50

story from the Chaos Communication Communication Congress

2:52

where I am this is a talk

2:54

given by Redford Q 3k and mr.

2:57

Tick Unbreaking

3:00

trains uncovering shady behavior. This is

3:02

just one of those Incredible

3:05

hacker stories that you kind of have to

3:07

see to believe you you really should all

3:09

go watch the talk So the link is

3:11

over on the hackaday page The

3:13

long and the short story is that

3:15

a company in Poland that has

3:18

a contract to repair and service

3:20

locomotives couldn't get them fixed

3:22

and working and Wanted

3:25

to know why and so according

3:27

to them Anyway, the company googled

3:29

Polish hackers and came up with

3:32

Redford Q 3k of mr. Tick's

3:34

names Called them up and

3:36

said hey We think

3:38

there's something with the firmware

3:40

on this train like ECU

3:43

controller thing Can you poke

3:45

at it and see if you can make these

3:47

trains run again? And they said Yeah,

3:50

we'll give it a shot and then they're like,

3:52

oh by the way, you have two weeks to

3:54

do it In fact, they managed to get the

3:56

trains running about 43 minutes

3:59

before the deadline they had been

4:01

given. So the trains are basically

4:03

run entirely over CAN bus and

4:05

are programmed in this kind of

4:07

weird archaic programming language. They managed

4:09

to a sniff the CAN bus

4:11

and find out that it was

4:13

sending some zeros essentially where it

4:15

should have been sending ones. That

4:17

is the controller was telling the

4:19

motors not to fire up when

4:21

they should have been spooling up

4:23

even though the you know even

4:25

though they were throwing the lever

4:27

up front. And the reason for

4:29

this is that it

4:32

looks like from reverse engineering

4:34

the software the software was

4:36

intentionally bricking itself. The software

4:38

was intentionally failing

4:40

after a certain period of time

4:43

and they ended up having access

4:45

to I think 30 individual locomotives

4:47

and dumping the firmware from all

4:50

of these reverse engineering it

4:52

looking at it. Not only could they make

4:54

them run but they found

4:56

the code that made them not run

4:59

which included things like if it's

5:01

the 21st of the month and

5:03

the train hasn't run in four

5:05

days don't fire up the motors.

5:08

The absolute best as far as I

5:10

can tell which made this very clearly

5:12

kind of an active I

5:15

can't say it's an active sabotage this

5:17

is an ongoing legal case. Malfeasance perhaps.

5:19

A parent malfeasance. A

5:23

legit malfeasance is. Is

5:25

that the manufacturer put things

5:27

in there like geofencing against

5:29

a bunch of their rival

5:31

companies that were servicing the

5:33

trains to make them not

5:35

work when they were in

5:37

their stockyards but able to

5:40

work when they are elsewhere.

5:42

And in fact they had

5:44

a flag that made it not work

5:46

when it was in their own stockyards

5:48

but they also were able to turn

5:51

it on and off so they had

5:53

tested this geofencing thing apparently and

5:56

then implemented it in actual

5:58

real trains. And so

6:01

this is just a phenomenal talk

6:03

and it kind of brings home

6:05

the best of the reasons why

6:07

we hack. And that is some

6:09

companies will do technologically bad things.

6:11

And if you can reverse engineer

6:13

their firmware, you can figure out

6:16

that they're doing this and

6:18

hold them accountable. And that's exactly what happened

6:20

here. But go watch the talk. Trust me

6:22

on this one. So I

6:24

did think the geofencing out your

6:26

competitors' repair yards was particularly egregious.

6:29

That's awesome. You know, because up till

6:31

then I was kind of like, well,

6:33

let's try to be open-minded. Maybe they

6:35

have a reason, but that's really that

6:37

seems over the top. And I think

6:39

I always have a resistance to getting

6:41

the courts involved in anything like this

6:43

because that's never good. Right. It's just

6:46

usually the courts do not make great decisions

6:49

about technical stuff. You know, going all the

6:51

way back to the, well, you can't see

6:53

the copyright message in the ROM. So therefore

6:55

it's not copyrighted. You know, that was back

6:57

in the 70s or whatever. But, you know,

7:00

this does seem like a big deal. And

7:02

I could not help but think of the

7:04

McDonald's ice cream machine fiasco, right? Which has

7:06

a lot of these same sort of shadows

7:09

in it where, you know, you say, well,

7:11

we did publish the codes, but nobody bothered

7:13

to read them. And so when somebody made

7:15

a raspberry pie to read them, we didn't

7:17

like that. So then we started, you know,

7:19

saying, oh, it's not safe and it might

7:21

be dangerous. And, you know, I don't think

7:23

it's dangerous to have a raspberry pie connected to

7:25

your ice cream machine. So it did kind of

7:27

remind me of that. And it's the same kind

7:29

of thing. Once it devolves into a legal battle,

7:32

it just seems like nobody really wins except perhaps

7:34

the lawyers. But I do

7:36

agree this seemed to be especially

7:38

egregious and maybe even

7:40

more mean-spirited than the ice cream

7:42

hack. So they looked at

7:44

all of these trains and they all had

7:46

different triggers in them. Some of them stopped

7:49

working after the odometer got

7:51

to a million kilometers. Some

7:54

of them stopped working after the train was

7:56

inactive for more than 21 hours. Some

7:59

of them stopped. working on the 21st

8:01

of the month. And that one,

8:03

there was actually a bug in

8:06

the code and tongue-in-cheek Q3K suggested

8:08

that the 21st be a

8:10

Polish national holiday, the day the trains

8:13

don't run. And I thought that was

8:15

pretty sweet. Oh man, there's so

8:17

many crazy details in this talk. One of

8:20

the things that I really love also is

8:22

that they had access to one of these

8:24

units, they dumped the ROMs and then they

8:26

sent it back to the manufacturer and told

8:29

them a little bit of what they had

8:31

found and what the problem was. The

8:34

manufacturer sends it back, working of

8:36

course, with a new firmware that has,

8:38

as you mentioned, strangely

8:40

enough, copyright notices in the

8:42

ROM and says, you know,

8:44

if you're dumping this ROM now, you're

8:47

breaking the law or whatever, right?

8:49

And the funny thing is they

8:51

changed a number of other things.

8:53

It's probably illegal to change the

8:56

ROMs on the ECU of a

8:59

train without getting it recertified. So

9:01

it's very likely that not only

9:03

did they do something that is,

9:06

you know, trying to cover their

9:08

tracks and protect them legally from

9:10

this incredible storm that's about to

9:13

hit them, but they probably also

9:15

put trains back on the rails

9:17

that did not have properly vetted firmware in

9:19

them. I'm not sure what the safety regulations

9:22

for trains are, but you would think that'd

9:24

be something, you know, certainly like an airplane,

9:26

you couldn't do that. You can't just say,

9:28

oh, here's some new firmware we slapped together.

9:30

Let's throw it on an airplane. They hid

9:32

cheat codes essentially in the firmware that reactivated

9:35

the motors and stuff like that. I mean,

9:37

because they didn't want to do tons of

9:39

work, they didn't want to have to reflash

9:41

the firmware to get the trains running again.

9:43

So there's actually a two

9:46

lever command sequence you can give

9:48

the train and then it'll start running

9:50

again. And that's actually what

9:52

these guys found out about all these

9:55

trains. They actually didn't end up changing

9:57

any of the firmware on the trains.

10:00

did was they read it, dumped

10:02

it, reverse engineered it, discovered the cheat

10:04

codes that were embedded in the firmware,

10:06

and then just replayed them, you know,

10:09

push this lever here while pressing this

10:11

button and hitting the brakes. And

10:13

then that made the train run again. Yeah.

10:16

Well, and it kind of reminded me too of

10:18

some of the old copy protection schemes that you

10:20

used to see on like games, you know, and

10:22

if you dig down far enough, there was always

10:24

some piece of code that said, did

10:26

I see my copy protection? Yes, no. And you

10:28

could always at least reverse the sense of that,

10:30

right? So then it

10:33

wouldn't work with the hardware dongle or whatever

10:35

the protection device was, but it would work

10:37

without it. You know, for a

10:39

long time, that was a big emphasis on people

10:41

hacking was finding ways around the copy protection for

10:43

games. They kind of reminded me of that a

10:46

little bit. Glad those

10:48

days are gone, but that kind

10:50

of behavior is absolutely unacceptable in

10:52

large public sector

10:54

infrastructure. So I waxed

10:56

nostalgic for my first one this

10:59

week, and it was actually a

11:01

piece that Chloe Abenesu, I

11:03

think at PC magazine wrote, which was

11:05

a tech obituary for all the tech

11:08

gadgets and services that died in 2023.

11:11

You know, and most of them were

11:14

really consumer oriented. You know, Google obviously

11:16

had killed 20 things like they do

11:18

every year, including I was

11:20

amused to see Google glass died

11:23

again, because they had a commercial version

11:25

of glass that nobody wanted either. You know,

11:27

that's one of those things where man sitting

11:29

in a room somewhere, you would assume that

11:31

would just sell like gangbusters. And it just

11:33

doesn't. And I don't know, but there's probably

11:35

there must be some larger reason for that.

11:38

But it ranged to other things to

11:40

Netflix, apparently you stopped shipping DVDs, which

11:42

I didn't know they still were shipping

11:44

DVDs, and just a lot of

11:46

different things like that. But it got me

11:48

to thinking, you know, those were all really

11:50

kind of consumer oriented. And we're all kind

11:52

of interested in that. But it really made

11:54

me think about what have we lost in

11:56

our sector, right in the hackerspace. So

11:59

what products. have kind of come and gone.

12:01

You know, some of the 3d printing stuff

12:03

has started to fall out. So XYZ

12:06

printing, you know, they were

12:08

infamous for having the closed

12:10

filament. They're gone. I

12:12

guess the sculpt your marketplace was gone. And

12:14

I was hoping in the comments, maybe people

12:16

would know about some other little obscure things

12:18

that had come and gone, but surprisingly, I

12:20

didn't see a lot that just made me

12:22

think, Oh yeah, you know, that's a big

12:25

thing, but I think there's a lot of

12:27

changes in the industry and maybe we're due

12:29

for a shake out. So maybe 2024,

12:31

there will be more things

12:33

shaken out. Uh, and I think part of

12:35

it is too, is we've got so many

12:37

big players now that maybe the things that

12:39

kind of came and went, you didn't even

12:41

notice. So it's one thing when

12:44

Google shutters something down because they're very visible,

12:46

it's another thing when, you know, the Williams

12:48

is a start their garage company and it

12:50

just doesn't go anywhere and they go back

12:52

to writing for Hackaday. Right. So, you know,

12:54

I think that's maybe less noticeable, but I

12:56

imagine there's a lot of that going on

12:58

as well. I think the other thing

13:00

that was interesting to me about this

13:02

is the fact that, you know, we

13:04

are seeing a lot of

13:06

stuff that subscription based seemed to go

13:09

away. So, you know, Google

13:11

that back on Google, since they kill everything,

13:13

they had offered the deal where you say,

13:15

Oh, if you pay us so much a

13:17

year, every couple of years, we'll give you

13:19

a new pixel phone and you'll get free

13:21

access and, you know, all this stuff. And

13:23

I guess if you signed up for that

13:25

tough because they kind of canceled it, that's

13:27

interesting too, because I fear the, you know,

13:29

we won't sell you anything. We're going to give

13:31

it to you as a service, some because of

13:33

what we just talked about with the trains, right?

13:35

Because once you own my phone and I don't,

13:38

you can justify getting away with a lot more naughty

13:40

things on my phone than if I own it. But

13:43

I, it seems like maybe the market is rejecting

13:45

that. So that was kind of a cool takeaway

13:47

from that. I think I'm looking down this list

13:49

on PC magazine and you know, if, if I

13:52

get to be hardware guy versus software guy, I

13:54

will note that these are like 90 something

13:57

percent software that God

13:59

discontinued. or like you said,

14:01

they're software services that got discontinued.

14:03

So few of them are actually

14:06

physical things out there in the world.

14:08

It's just like we thought we would

14:10

sell you this software and now we're

14:12

not anymore. And yeah, well, easy come,

14:14

easy go, right? Well, I mean, Google

14:16

Glass certainly was a piece of hardware,

14:18

but you're right. It's in the minority.

14:21

I don't know if their business model was...

14:23

I guess they sold it to you for

14:26

outrageous sums of money. So they probably were

14:28

counting on it being the hardware pushing the

14:30

device. Well, not that I'm in any position

14:32

to give Google advice, but it

14:34

always strikes me that they don't

14:37

have the lesson we learned back with

14:39

the CPM computers, which is that no

14:41

one wants to buy computers. They want

14:43

to buy applications, right? So you didn't

14:46

really buy a computer. You bought Wordstar

14:48

and you bought VisiCalc or whatever the

14:50

early spreadsheet program was. And so it

14:52

seems to me that's what is missing here

14:54

is you don't need the, hey, isn't that

14:57

cool, there's glasses and you can do a

14:59

web search on them. You need the killer

15:01

application that says, hey, I'm a surgeon and

15:03

I can get a tactical view of my

15:05

patient laying on the table through these glasses

15:07

or whatever. I don't know what the killer

15:09

app is because if I was, I'd probably

15:11

be doing that instead of this. But that's

15:14

what will sell it is when there's the

15:16

app, you just can't live without it and

15:18

you'll pay anything for the glasses. Just

15:20

saying I made the glasses, only

15:23

we get excited about stuff like that. I

15:26

think you're right. You're

15:28

saying app like software application, the

15:30

killer app, but I'm saying what's

15:32

the real physical world application, but

15:35

we're both saying the same thing.

15:37

Right. And I mean, it's just like

15:39

if you say, look at the early computers when it

15:41

was just the weird people that had them and you

15:43

said, oh, we did my bio rhythms and I kept

15:45

my recipes on them. And I don't

15:48

have to say, well, why do I make this recipe for

15:50

six when it's for four? I just tell it I want

15:52

six people. No one cared about any of that. So

15:54

that was there, but no one cared. And what

15:56

people really cared about at first were the

15:58

spreadsheets and the word. processors and eventually

16:00

the real surprise was is they were

16:03

interested in music, media and talking to

16:05

each other, right? And that turned out

16:07

the killer app was not just having

16:09

a computer but having your computer talk

16:12

to everybody else's computer. Well it's wintertime

16:14

here and that means the fall semester

16:16

is over and that means Cornell's ECE

16:18

4760 class. This is a micro controller

16:24

class where the students all have

16:26

to, through the course of the semester,

16:28

put together a final project and

16:30

show it off on the internet.

16:32

This class used to be run

16:35

by Bruce Land, it's now run

16:37

by Hunter Adams, but these student

16:39

projects are no less awesome. So

16:41

expect to see a bunch of

16:43

them coming out in the next

16:45

few weeks. The one I wanted

16:47

to cover is Raspberry Pi Pico

16:49

Mandelbrot Computation. This is a really

16:51

cool project done by Ryan Colm

16:53

and Ignacio de Jesus Romojimenez in

16:55

which they set up a parallel

16:58

computer that they're calling the Computron

17:00

to calculate the Mandelbrot set and display

17:02

it on a VGA monitor.

17:05

The Computron is a parallel computer

17:08

in the sense that they have

17:10

one Pico that's responsible for doing

17:12

the graphics and projecting that onto

17:14

the VGA monitor and then they

17:16

can plug in a whole bunch

17:18

of other Pico's with kind of

17:21

compute software on them and spread

17:23

up the work amongst them. They

17:25

all talk over an I2C bus

17:27

which provides a simple kind of

17:30

robust data backbone for them and then

17:32

the main computer prints it out to

17:34

the screen. Their write-up is superb and

17:37

it ends up coming to the conclusion

17:39

that a lot of people come to

17:41

when they're like, I'll just take this

17:43

problem and parallelize it and that is

17:46

that you really don't get a end

17:49

time speed up if you throw end

17:51

computers at the problem and they find

17:54

that in spades here. They get kind

17:56

of you know an 80% increase in speed

18:00

when they go from one Pico to

18:02

two Pico's working on it. But they

18:04

have a beautiful graph where they show

18:06

it taper off. And in fact, they

18:08

have the really strangest thing, which is

18:10

that sometimes they'll have little jumps in

18:12

their performance where you would expect the

18:14

performance to keep increasing as you throw

18:17

more processors in it, but it doesn't

18:19

or it stalls. And what they think

18:21

is going on here is when you

18:23

divide the problem by two, it's pretty

18:25

evenly split among the two. But when

18:27

you divide it by eight, one

18:30

of the processors gets the hardest problem

18:32

every time through as it goes through

18:34

this kind of round robin, you take

18:36

the slice, you take the slice, you

18:39

take the slice procedure. And that poor

18:41

one processor, long story short, it's

18:43

so tempting to just throw massive parallelism at

18:45

a problem when you have a problem like

18:47

this, especially when you have like cheap devices.

18:49

You're like, I need it to go twice

18:51

as fast. I'll just use two of them.

18:53

No, you'll use three of them. And then

18:56

it's like, I need it to go eight

18:58

times as fast. I'll just use eight of

19:00

them. And the answer there I think is

19:02

you're gonna have to use 32 of them

19:04

or step up to a bigger

19:06

processor. You know, the I2C bus

19:08

almost had to be some factor to that.

19:11

You normally see some sort of higher

19:13

end fabric or shared memory, you know,

19:15

but this was such a great effort

19:18

for a student project. And it's

19:20

always one of the high points of the year

19:22

when Cornell sends over their batch of student projects

19:24

because it's always amazing. And this one certainly was

19:26

very interesting. You know, they sent it over in

19:29

a block and I think there was like 47,

19:31

I wanna say, there

19:33

was some huge number of projects, but a

19:35

lot of them had pretty interesting titles, you

19:37

know, gesture-based scheme or something. And some of

19:39

them would say like, Computron, and you're like,

19:42

well, I don't know what that is. So

19:44

part of our job was to kind of

19:46

dig through and go, oh, this is where

19:48

they used a bunch of Raspberry Pis and

19:50

a parallel processor. And then that's what Computron

19:52

is. So, you know, that might be part

19:54

of the student work there is to make

19:56

sure we understand what you're doing. Oh

19:58

man, you give me a project called- Computron and

20:00

I am digging into it. I'll be

20:02

like, that's bait for me. I'm like,

20:04

what the heck is a Computron? What

20:07

I really love about this Cornell class

20:10

is that all the students who take

20:12

it are graded on both the success

20:14

of their project, but the quality of

20:16

their documentation around it. And that's, I

20:19

think, why we've been covering these projects

20:21

for so long. I'd be really stoked

20:23

to see other engineering programs follow suit.

20:26

I mean, I'm sure that other schools

20:28

out there must be doing things

20:30

like this, where they give them an

20:32

end of the semester capstone project. And

20:35

it's like, how cool can you do

20:37

this? But by requiring the students to

20:39

document their project and make it available

20:41

to everyone else, it not only helps

20:44

each successive year of students do

20:47

cooler and cooler things, which we've

20:49

totally seen in the kind of

20:51

whatever, 10 years, 15 years that

20:54

Hackaday's been covering this ECE class

20:56

here. So the students get to

20:58

benefit from each other's work, but

21:01

then we get to write it

21:03

up too. And then everybody gets

21:05

to benefit from the students' work.

21:07

And I think that's really what's

21:09

super cool about this particular ECE

21:11

class. And why are other

21:14

professors out there not requiring their students

21:16

to document their work well and put

21:18

it up on the internet? If

21:20

you do, it offers them a

21:22

fantastic carrot, right? If

21:24

they want to put that extra effort

21:27

into it and make it look really

21:29

good or put more work into it

21:31

and document that super well, it just

21:33

makes such a huge reward for them

21:35

in terms of the ability

21:38

for them to get recognition for their hard

21:40

work over and above just getting an A

21:42

in the class. Yeah, if

21:45

you're an engineering professor who has

21:47

your students do a practical class

21:49

like this, give them a

21:51

documentation requirement and send us the links. We're

21:53

dying to see them. But I don't know

21:56

about you. If I'm interviewing somebody

21:58

and they said, oh, yeah, I've had three projects. features

22:00

on Hackaday, I'm hiring them, right? Oh, I

22:02

swear. I mean, look, featured

22:04

on Hackaday or not, going on the

22:06

job market can point to this work

22:09

and say, here, look at this. And

22:11

that's like... Absolutely. Builds

22:13

your portfolio. It's an interesting thing that you've

22:15

done. It shows you're competent and well-rounded, and

22:17

who knows what else. Like, it's a win-win

22:19

for everybody. It's like seven wins. Okay, my

22:21

next pick for the week was from Keep

22:24

Making. You know, it's one of these things

22:26

after you read about it, you think, why

22:28

didn't I think of that? You

22:30

know, you've owned for a long time that if you're going

22:33

to 3D print some stuff, it makes sense to fill up

22:35

your build plate and try to print as much as you

22:37

can in one pass. And you're

22:39

thinking in X and Y, but this article

22:41

is talking about actually filling up the build

22:43

volume in the Z axis as well. And

22:46

that's apparently not a super new idea, but

22:48

you don't see it very often. The

22:51

idea is kind of to print

22:53

pieces that are separated by just

22:55

a single-layer gap with ironed top

22:58

surfaces. And it's almost like

23:00

printing support pieces, except instead of the

23:02

support just ripping off, you essentially rip

23:04

off finished pieces and then rip off

23:06

more finished pieces and rip off more

23:08

finished pieces. The videos were

23:10

really well done in that

23:12

you could see how they were kind of

23:14

stuck together. He'd take a screw and just

23:16

use them to pop open the little pieces

23:18

where it was still stuck together. Obviously, one

23:21

side of the piece isn't going to be as

23:23

well finished as the other. In this particular case,

23:25

he's making things that hang on the wall, so

23:28

you really don't care what the wall-facing side looks

23:30

like as long as it's not too grody. It

23:33

didn't look like it was that bad to begin with. So

23:36

I'm kind of interested to try that out

23:38

myself. I don't always do large volumes of

23:40

prints where I'm printing 50 things at one

23:42

time, but that gives you

23:44

a lot of options for producing more things

23:47

than just going to the right, the left,

23:49

up and down on the bed. Of

23:51

course, I don't know if you could do

23:53

this with resin printing. That has its own

23:55

advantages because then filling up the X and

23:57

Y on a resin printer is easy because...

24:00

It doesn't take any more time to print an

24:02

empty bed than a full bed. But obviously, this

24:04

would add time in that case if you're going

24:06

up in the z-axis. But I don't know if

24:08

those would separate quite as well or not, but

24:10

it'd be something interesting to experiment with. I

24:12

guess it only works for things that

24:14

are kind of relatively flat in a

24:17

way. Cuz if you have too much

24:19

kind of vertical topology, it

24:21

means you'll have to think about putting fill

24:23

in between the different object layers. It's

24:26

a really neat kind of switch in your

24:29

thinking to think about multiplying the things, not

24:31

just left and right, but also up and

24:34

down. It made me wonder if the

24:36

slicers couldn't support something like this, where

24:38

you could actually build little

24:40

support pillars in between the layers.

24:43

Just like you do now for tree support,

24:45

for example, that could all be done automatically

24:47

and you could get nice stacks even if

24:49

they weren't flat, like you suggest. That

24:52

would be super clever. And if you add holes

24:54

in it, you could even do, yeah, you could

24:56

run supports up the vertical holes and

24:58

tubes and stuff. Oh, that would be really neat.

25:00

Yeah, a lot of fun things to think about

25:02

there. All right, bringing up the

25:05

rear for me, absorbing traffic noise

25:07

with bricks using Helmholtz resonators. And

25:09

I think if I had my

25:11

life to live over again, one

25:13

of my crazy dream jobs has

25:15

always been kind of an acoustic

25:17

architect. There are people who get

25:20

paid good money to design symphony

25:22

halls. But when I walk into

25:24

a number of other spaces, I'm

25:26

always kind of like, sometimes they

25:28

have really harsh echoes and sometimes

25:30

spaces are so loud, you can't

25:32

even hear the person you're talking to. And

25:36

traffic noise can be overwhelming. And if

25:38

you have big flat

25:40

walls, it can kind of get seemingly

25:42

amplified. That's kind of the project

25:44

that is being undertaken here, is

25:47

how to beat that down. And

25:49

in particular, he's using cleverly

25:52

designed stackable bricks to absorb

25:54

some of the energy out

25:56

of the waves and

25:58

put a notch into the level of. noise

26:00

in an environment. In this demo

26:03

he's using clay as the material

26:05

and making kind of bricks that

26:07

have cavities in them that want

26:10

to resonate at certain frequencies but

26:12

then because the bricks aren't you

26:14

know perfectly hard they absorb all

26:17

of the energy in those frequencies. So

26:20

you can think of it you know

26:22

like kind of any tuned system except

26:24

a tuned system where there's a lot

26:26

of resistance so it dissipates the energy

26:28

out randomly. And it's a

26:31

really neat design here. He starts off

26:33

by doing 3D printing to

26:35

make these kind of extremely complicated

26:37

clay brick shapes that have exactly

26:40

the right interior volume to absorb

26:43

kind of low frequency road noise.

26:45

And then they end

26:47

up cracking. There's a whole bunch of

26:49

reasons and he actually goes through three

26:51

or four kind of failed iterations here.

26:53

He ends up slip casting into 3D

26:56

printed forms to make the

26:58

bricks and that ends up working. The thing

27:01

that is really clever about the

27:03

design he ends up settling on

27:05

and this is why you'd want

27:07

to do it using modern design

27:09

techniques is that they have not

27:11

only a resonant cavity inside the

27:13

brick but they're shaped on the

27:15

outside so that the spaces in

27:18

between them also makes

27:20

a resonant cavity. And

27:22

because of this kind of irregular shape

27:24

you can only stack them in exactly

27:26

the right way to make these shapes

27:29

both the interior and the exterior

27:31

one. Just it's a really sweet

27:33

design and if you've never thought

27:35

about how you would go about

27:38

making hollow arbitrary shaped

27:40

funny bricks like that's

27:42

a cool problem to have and to have

27:44

to solve and he goes through his work

27:47

in that direction here too. Really just a fun

27:49

talk you should check it out. Well

27:51

I'm always surprised at how poorly I

27:54

can predict what comments will be on

27:56

any particular hackaday article. If you read

27:58

the comments on this one... almost

28:00

to a one saying, well that's great

28:02

until the possums nest in those hollow

28:05

cavities, right? Or the

28:07

insects, birds, pigeons. That probably has some

28:09

merit to it. I'm not saying it's

28:11

insurmountable, but yeah, it seems like they

28:13

would be a maintenance issue. But

28:16

yeah, what an interesting exercise and

28:18

shape. And I don't know,

28:20

I'm not as talented as you

28:22

are with hearing the echoes, but I will

28:24

say a room with good acoustics is a

28:26

thing of joy. I don't always understand why

28:28

it's the way it is, but certainly makes

28:30

a big difference. Acoustic architecture, I'm

28:32

sure it's a field. I'm sure there are people who

28:34

make their living doing this. In

28:36

some alternate universe, I'm one of them.

28:39

My last one this week is from

28:41

Veritasium. I have to say, this is

28:43

probably something that won't surprise some people,

28:45

but for me, I have

28:48

had this lifelong obsession with how in the world

28:50

is a sewing machine work, and I just have

28:52

never taken the time to figure that out. It's

28:55

one of those things, I think, hackaday readers

28:57

in general, we like to think we know

28:59

how the world works. So why does your

29:02

cell phone work? Why does air conditioner work?

29:04

And we usually know those things. But

29:06

I was never able to really understand how

29:09

a sewing machine takes a needle, jams it

29:11

through some fabric, and stitches it together. What

29:13

was interesting about this video is it was

29:16

very accessible, but also he had built

29:18

a large scale demonstrator with a

29:20

needle the size of a garden

29:22

stake, I guess, and big giant

29:24

belts and pulleys and

29:27

the thread looks more like

29:29

twine and is able

29:31

to demonstrate all the different working pieces.

29:34

It's amazing when you think about it is, if

29:37

you said today, let's make a machine that binds

29:39

fabric together, well, you got a lot of options,

29:41

right? You could say, well, we'll get a stepper

29:44

motor, we'll have some little arm that goes and

29:46

pulls this here and there. All this

29:48

was back in the 1800s and earlier

29:50

where you didn't have all that. So

29:52

it's all these clever contraptions with cams

29:55

and hooks. And I just

29:57

thought it was a super interesting piece. And

29:59

I'm so. I'm certain I'm in the minority of people

30:01

who didn't know how a sewing machine works, but

30:04

I was really happy to run across this.

30:06

It's something that's been in the back of

30:08

my mind for years. I'm certain you're not

30:10

in the minority. It's a pretty crazy mechanism.

30:13

And the rotating claw that pulls

30:15

the loop through is just, I

30:18

would not have thought of that a priori. Well, you

30:20

got to wonder how many iterations it took to get

30:22

to that too, right? That's right. How

30:25

many times you said, oh, that didn't work. Let me try this.

30:28

You couldn't 3D print them in those days. So

30:30

that was probably a lot of work. And the

30:32

advantage to being able to make a working one

30:34

was so huge. Like

30:36

before, when everybody had to sew by hand,

30:38

you'd be king of the world if you

30:40

could make a machine that would sew. Well

30:43

that was actually one of the things that was in

30:45

the video was he was saying, and I don't know

30:47

what the source for this is. He was saying that

30:49

in 1900, a family would spend 15% of

30:52

their income on clothes. But in 2003, that number is

30:54

less than 4%. And

30:58

yet you will have way more clothes. The

31:00

family will have more clothes in 2003 than they had in 1900. But

31:05

yeah, people made fortunes. And especially, it

31:07

was kind of interesting. Singer, who you

31:09

associate with sewing machines, he didn't actually

31:11

invent any of it. He just saw

31:13

the value of it and bought up

31:15

patents and commercialized cheap sewing machines. And

31:18

that's where Singer came from. Not

31:20

to mention 50,000 year old needles. Good

31:22

God. Who was thinking that up 50,000 years ago?

31:25

That's amazing. People have been sewing for a long time.

31:33

All right, my first quick hack this

31:35

week is veteran SpaceX booster lost to

31:37

rough seas. And this

31:39

is a piece of news coming

31:41

from SpaceX naturally, written up by

31:43

our own space man, Tom Nardi.

31:45

What happened is they landed

31:48

one of their boosters as they

31:50

often do, except this time

31:52

due to rough seas, it fell

31:54

over and got destroyed. But

31:57

the booster in particular is one that had

31:59

made 15 launches, including

32:01

some historical ones. So

32:03

Tom wrote up a brief eulogy for

32:05

B1058 here. Give

32:09

it a read, it's an interesting view

32:11

into kind of the new space situation.

32:13

But speaking of old space, Lift

32:16

Off, The Origin of the Countdown,

32:18

is a long form piece written

32:21

by Cristina Panos. I'm mentioning it

32:23

here because of the super cool

32:25

tidbit that the countdown may have

32:28

been invented for drama in

32:30

a film before it got

32:32

used for launching actual rockets. Turns

32:34

out to be useful, of course.

32:36

Gets everyone in sync on the

32:38

same page, but this is a

32:40

case of life imitating art. And

32:43

last up, Tom Stanton, building

32:45

a rad supercapacitor RC plane.

32:47

This is really fun, despite

32:49

the fact that supercapacitors have

32:51

a lot less energy density

32:54

than a comparable lithium-ion battery.

32:56

Tom wants to make one

32:58

because he already has a

33:00

hand-cranked charger generator to fire

33:02

it up with. And supercapacitors

33:04

charge and discharge very easily, very

33:07

readily, and can put out large

33:09

current, of course. Here he's turning

33:11

it into a radio-controlled plane that he

33:14

can just go zip, zip, zip, charge it up at the

33:16

field, and then give it a fly. He

33:18

also deals with the real downside

33:20

of supercapacitors, and that is that

33:23

their voltage basically starts dropping from

33:25

the minute they start discharging. They

33:28

have a capacitor-like voltage roll-off, and

33:30

how you deal with that and

33:32

get the plane home safe when

33:35

the motors can't turn anymore is

33:37

an interesting problem that he looks

33:39

into here. My three

33:41

quick hacks for the week. Danny Lewis

33:44

had an interesting post about

33:46

how to build a guitar for $30 using parts

33:48

from Amazon. So

33:51

all my cool friends build guitars. I have

33:53

no musical talent, so I don't, but I

33:55

always suspected it would take more than $30 and

33:58

this article shows that that's not necessary. necessarily the

34:00

case. My second one

34:02

was another one of Hunter's students'

34:05

projects from Cornell. Giacomo

34:07

Cuomo and Sophia Lynn had a

34:09

talking ohm meter that spits out

34:11

color bands for you. And

34:14

I kind of described it as a

34:16

multi-mode ohm meter in that

34:18

it measures resistance and it's able to

34:20

actually speak the resistance, but it also

34:22

has like a giant model resistor with

34:24

multicolor LEDs on it. And it actually

34:27

shows you the color bands on

34:29

the fake resistor of what the real resistor

34:32

value is. It's one of those projects that's

34:34

probably not very practical but very cool. Last

34:37

but not least, Diode Gone Wild, always

34:39

loved that name. It

34:41

had an interesting video on how

34:43

wire changes resistance by temperature and

34:46

how you can use that

34:48

to measure temperature in circuits.

34:50

So obviously that takes

34:52

a lot of wire and or a

34:54

very precise resistance measurement, but if you

34:57

ever wondered, you know, how hot is

34:59

that transformer getting? That's

35:01

one way to do it is to measure the change

35:03

in resistance in the wire in the winding. All

35:11

right, that brings us to our Can't

35:14

Miss articles. These are long form pieces

35:16

written by our fantastic Haggaday writing staff.

35:18

This week I wanted to pick Dan

35:20

Maloney's Keeping Watch Over the Oceans with

35:23

Data Buoys. And this is another

35:25

one in the series that

35:27

at least among us Haggaday writers,

35:29

he's calling remotely interesting, which

35:31

I love. I wish he'd used

35:34

that in print because these are

35:36

all remote measurement devices and how

35:38

they work. In this case, he's talking

35:40

about ocean buoys that both measure

35:43

temperature, wind speed, wave height,

35:45

all sorts of things and help give us

35:48

a better picture of what the

35:50

globe's weather is like, especially out

35:52

over the seas where it's otherwise

35:54

harder to measure. The thing that

35:56

I learned from this that I

35:58

hadn't thought about before. was how

36:01

hard it is to connect

36:03

to more deep sea buoys

36:05

to the ground. And

36:07

in particular, there are all

36:10

these multiple material, multi-section cables

36:12

that you have to use

36:15

if you're going down really deep. Because if you think

36:17

about it, naively I'm like,

36:19

oh, well, they just must have a chain

36:21

that goes down to the ocean floor. And

36:24

yeah, that's fine if the ocean floor is

36:26

like 30 feet down. But

36:29

if you've got like miles and miles or

36:31

even just hundreds, thousands of meters

36:34

of steel cable down there,

36:36

that's clearly not going to do

36:38

it. And so they end up

36:41

using these fun mixes of nylon

36:43

and polypropylene lines that float

36:45

better than nylon lines and all

36:47

of these with floats on them.

36:50

There's a whole engineering problem in

36:53

designing the mooring systems that keep

36:55

these buoys basically in the same

36:57

place. I thought that was really

37:00

neat. Of course, there's all the standard

37:02

stuff like how you design the buoys

37:04

to be rugged enough that they can

37:06

withstand high seas. And Dan

37:09

actually points it out in one of these.

37:11

There's a buoy with a cage on it

37:13

that prevents seals from climbing up on top

37:15

of it and maybe messing

37:17

up the instrumentation. These

37:20

things are put out in the

37:22

roughest environment for electrical devices,

37:25

right? Take the middle of

37:27

the ocean with nasty waves.

37:30

And then they're supposed to be

37:32

tethered to the ocean floor, stay

37:35

basically put, and they need enough

37:37

electricity, enough generating capacity, whether gas

37:39

or solar, to keep

37:41

running and keep sending their data

37:43

back to us here on the

37:45

land. So it's a really neat

37:47

problem. And designing

37:50

scientific deep ocean buoys is

37:52

just one more of those

37:55

kind of remotely interesting sensor

37:57

things. And I'm happy to read this

37:59

one. Yeah, this got me nostalgic

38:01

because one of my first jobs was at

38:04

the same place where NOAA had a

38:06

big operation for data buoys. I

38:09

didn't have any direct involvement in it. But

38:11

back in the late 70s, early 80s, this

38:13

was way more difficult than it is now.

38:17

And they had all the problems with

38:19

sending data, so you had very precise time

38:21

measurement. Now, we didn't have GPS, right?

38:23

So you had to figure out the time

38:26

so that when your one minute of

38:28

data on the satellite came up, you

38:30

could squirt that data up over the satellite

38:32

and not interfere with everybody else who

38:34

was going to be using a different minute,

38:37

things like that. So my guess is things

38:39

are a lot easier now. So I know

38:41

if they're close to shore, sometimes they use

38:43

cell modems. And that was all unheard of

38:45

in those days. They do have

38:47

a lot of free floating buoys as well.

38:50

So even though you're right, it's amazing what

38:52

all they do to anchor something in 6,000

38:55

years of ocean, some

38:57

of them are actually just floating around. And

39:01

one of the things that I don't think Dan

39:03

mentioned, but one of the reasons I think there's

39:05

a lot of money put into these is at

39:07

least at a certain point in time, they were

39:09

very interested in the ocean conditions for where the

39:11

submarines might be coming over. And

39:14

that was a big part of this as

39:16

well, was picking up data about

39:18

ocean salinity, thermoclines, things like

39:20

that. So I feel like

39:22

there was probably some other

39:24

non-civilian use of some of this data, at

39:26

least over part of the time, that it

39:29

was operational. But it's an amazing

39:31

network. And yeah, Dan did a

39:33

great job of writing it up. He did mention,

39:35

by the way, I was also

39:37

dismayed he didn't use remotely interesting

39:39

in the title, but he does

39:41

say towards the end, he said

39:43

something about other remotely interesting articles.

39:46

So I guess he's kind of got that

39:48

as a series, but it's not actually in the

39:50

title. So we ought to fix that. We ought

39:52

at least make it the series name. Well he's

39:54

actually tagged them all as a series retroactively and

39:56

put them all down at the bottom of this.

39:59

Yeah. If you're interested in following him out,

40:01

you actually can find them in

40:03

this one or any of his others in

40:05

the series. I think, too, I just wanted

40:07

to shout out real quick where his no-snow

40:10

monitoring snowpack with the

40:13

SnowTel network because that's

40:15

a particularly cool device. And

40:18

then feeling the heat, railway

40:20

defect detection system where

40:22

they basically have heat cameras that look at

40:24

train wheels as they go by and see

40:26

if they're getting too hot, which would indicate

40:29

that a bearing is busted or something.

40:31

Both of these are really, really

40:33

cool and they're kind of, what,

40:35

pieces of essential remote sensing infrastructure

40:38

that keep the world running smoothly

40:40

but are somehow, you know, I

40:42

hadn't known about any of them

40:44

before reading these articles. So to

40:47

that extent, at least, you know,

40:49

invisible to our normal everyday experience.

40:52

Yeah, there's a lot of strange stuff out there. Yeah,

40:54

I can't wait to see what he comes up with

40:56

next. Well, my pick this week

40:58

was Lew and Day. How do

41:00

you test if an EPROM can hold data for 100 years?

41:03

This is always an interesting topic to me. I

41:05

spent time working for Motorola where we did this

41:08

kind of stuff. And, you know, you say, well,

41:10

you know, this flash memory will hold data for

41:12

100 years. Well, we haven't

41:14

had flash memory for 100 years, so obviously

41:16

somebody's making a guess. And

41:18

how do they do that? You

41:20

know, Lew and does a great job

41:22

of explaining failure mechanisms and say, well,

41:24

okay, you know, as the electrons bleed

41:27

out of this or the

41:29

charge bleeds out of this gate, you

41:31

know, that's going to get worse over

41:33

time, but also as a temperature or

41:36

the humidity or whatever. And so you

41:38

wind up designing these tests where you

41:40

say, okay, me heating this up to,

41:43

you know, 150 degrees is going

41:45

to be the same as if it was at room temperature for 20

41:47

years. So now if I

41:49

can get it to last five years, I can safely

41:51

say it's, you know, five times 20, 500 or 100

41:53

years. And

41:57

whether or not that's really true or not, I

41:59

don't know because I don't know if anybody everybody's

42:01

ever actually going back to see if any of

42:03

that works. We barely have enough time on some

42:05

of these devices that maybe you could start actually

42:07

looking at were those predictions accurate or not. It's

42:10

kind of interesting though, they use

42:12

that for a lot of things, which I

42:14

didn't realize. They use it for archival paper

42:16

and inks, which I learned that reading this.

42:19

But at the end of the day, it's

42:21

kind of an estimate or a model, if

42:23

you will. When

42:25

you see the science fiction show where

42:27

700 years from now, somebody pulls

42:30

out something and it's still working and you say, that

42:33

flash drive wouldn't have lasted that long. Maybe it

42:35

would. We don't really know.

42:37

But certainly the data suggests that it

42:39

wouldn't. How

42:42

you actually got there is what Luin

42:44

kind of exposes. It's well worth the

42:46

read if you've ever wondered how those

42:48

numbers arrived at. What I like about

42:50

this is it is kind of based

42:52

in fundamental science at the end. He

42:54

says in this article, and I guess

42:57

I hadn't thought about it, that like

42:59

bit rot degradation of memory cells is

43:01

basically because of chemical reactions that

43:04

are going on inside. That

43:06

gets you the answer already

43:09

because chemical reactions increase with

43:11

heat as described by the

43:13

Arrhenius equation. You

43:15

can figure this out, right? You

43:17

increase the temperature by 10 degrees,

43:19

the reaction speed goes up by this

43:22

much, et cetera, et cetera. This is

43:24

true for chemical reactions. That

43:27

means it's true for how quickly

43:29

materials oxidize or things like

43:31

that. I don't know

43:34

if it's necessarily true for

43:36

how quickly trapped electrons diffuse

43:38

through a silicon barrier.

43:41

But actually, now that I think about it, it's

43:44

got to be, right? This is chemistry again. It

43:47

probably makes a whole ton of sense

43:49

to think about things this way. I

43:51

guess you could also think about whether

43:53

some of the bit rot is due

43:55

to cosmic rays, and then you'd

43:57

want to subject them to something.

44:00

some x-ray bombardment or something for what

44:02

do I know, right? But

44:04

the basic science here I think is really

44:06

sound in the sense that they're saying, look,

44:09

this has got to be a chemical

44:12

reaction that's causing the damage here

44:14

and so we know at

44:16

what rate chemical reactions speed up given different

44:18

temperatures. Let's just crank the heat up on

44:21

it. And of course that only

44:23

works till the thing melts. Yeah, you've got to

44:25

wonder, you know, and maybe this is a good

44:27

science fiction story, in a thousand years what

44:29

the archaeologists are going to make of all

44:31

this because presumably all of our storage media

44:34

will be pretty much impossible to read then.

44:36

So it's like, what is this? I don't

44:38

know. It must have had some religious significance,

44:40

you know. No, it's a CD-ROM, but

44:42

no one knows how to read it so you can't

44:44

see the Panda movie that was on it or whatever.

44:47

Maybe not. And it makes you wonder too,

44:50

just like we have techniques now where we

44:52

can pull writing off of things that they

44:54

used to think were lost forever, you know,

44:56

maybe they'll have some way to do something we

44:59

don't know about and figure out, oh yeah, this

45:01

is what used to be stored in that flash

45:03

memory or on that piece of magnetic tape. Who

45:05

knows what they'll develop. So if you want it to last

45:08

for 10,000 years, write it down

45:10

on paper in some good ink, though. I

45:12

have a whole bunch of, I have

45:15

a whole closet full of like CD-Rs

45:17

that are just rotting away right now.

45:19

I don't even dare look.

45:23

That wraps it up for this

45:25

week's Hackaday podcast. Thanks very much

45:27

for listening. If you'd like to

45:29

follow the links, head on over

45:31

to hackaday.com/podcast and if

45:33

you see anything cool or do

45:35

anything cool, write us. Tips at

45:37

hackaday.com. And until next week, keep

45:39

those hacks coming. What's

45:42

the German word for a piece of crap software?

45:45

Crap, why did I do that? Give

45:48

me one sec. I

45:50

knew you were gonna do that. I should have looked it up for

45:52

you. I

45:55

should have looked it up for you. Well,

45:57

apparently my phone's off. the

46:00

audio.