A decade after graduating college, Stephen finally did a differential equation for his job! That is some real engineering I tell you what.
The PinoTaur has reached production status but not without supply chain issues..OF COURSE! Bonus discussion about thermal management for PCBA.
Is there a statue of limitations on open source hardware projects? This week, Stephen and Parker dive into what open source means for both of them.
The MacroFab Engineering Podcast Useless Machine Contest Sponsored by Mouser Electronics is in full swing! We have cash prizes up for grabs. Contest Ends August 10, 2019. Check out the MacroFab Blog and Podcast Episode 175 for more contest details.
Visit our Public Slack Channel and join the conversation in between episodes!
Parker is an Electrical Engineer with backgrounds in Embedded System Design and Digital Signal Processing. He got his start in 2005 by hacking Nintendo consoles into portable gaming units. The following year he designed and produced an Atari 2600 video mod to allow the Atari to display a crisp, RF fuzz free picture on newer TVs. Over a thousand Atari video mods where produced by Parker from 2006 to 2011 and the mod is still made by other enthusiasts in the Atari community.
In 2006, Parker enrolled at The University of Texas at Austin as a Petroleum Engineer. After realizing electronics was his passion he switched majors in 2007 to Electrical and Computer Engineering. Following his previous background in making the Atari 2600 video mod, Parker decided to take more board layout classes and circuit design classes. Other areas of study include robotics, microcontroller theory and design, FPGA development with VHDL and Verilog, and image and signal processing with DSPs. In 2010, Parker won a Ti sponsored Launchpad programming and design contest that was held by the IEEE CS chapter at the University. Parker graduated with a BS in Electrical and Computer Engineering in the Spring of 2012.
In the Summer of 2012, Parker was hired on as an Electrical Engineer at Dynamic Perception to design and prototype new electronic products. Here, Parker learned about full product development cycles and honed his board layout skills. Seeing the difficulties in managing operations and FCC/CE compliance testing, Parker thought there had to be a better way for small electronic companies to get their product out in customer's hands.
Parker also runs the blog, longhornengineer.com, where he posts his personal projects, technical guides, and appnotes about board layout design and components.
Stephen Kraig began his electronics career by building musical oriented circuits in 2003. Stephen is an avid guitar player and, in his down time, manufactures audio electronics including guitar amplifiers, pedals, and pro audio gear. Stephen graduated with a BS in Electrical Engineering from Texas A&M University.
Special thanks to whixr over at Tymkrs for the intro and outro!
Welcome to the macro fab engineering podcast. We're your hosts Parker, Dolman
and Steven Craig.
This is episode 179. The macro engineering podcast uses machine contest sponsored by Mouser. Electronics is in full swing, we have cash prizes up for grabs. contest ends, August 10 2019. So get your projects entered, check out the macro fab blog and podcast episode 175 For more contest details.
So something's kind of unique about this podcast. Right, Parker?
Yeah, I think our microphones have bleed over.
Somehow they're bleeding. 1000 miles away from each other, or five feet. Dun, dun.
So I'm up here in Colorado visiting Steven.
Yeah, we're doing like you're up here for like 10 days or so. So
that sounds about right. I'm basically taking like the entire July 4 week off minus doing the podcast.
Awesome. Yeah. So this is the first in person podcast we've done in Gosh,
a year. Something like that. Whenever you left. Yeah. A year, something like that. Is it a year anniversary now? Because you've been up here? A little bit
over? Yeah, just a tad bit over. Cool. You're in a month, something like that. So yeah, we're we're recording down in the dungeon down in my basement?
Yes. It looks like a basement
or a dungeon. One or the other.
There's no chains on the walls or anything like that. So yeah,
Parker has come up to hang out, have some fun, but also working on a bunch of stuff. Like, I mean, given the fact that this is not like a two or three day trip, we kind of made a list of like, Let's knock out this and this and this. So we've been working on some projects and playing video games and drinking beer and throwing darts and all kinds of good stuff. Oh, yeah.
And so I've been working a lot on the penetrator. Finally. Basically, the last couple of months has just been like, looking that part's conceptual. Right? Yeah. And designing parts and like Eagle, making sure the footprints are right and stuff. But I was finally like, Okay, gotta start to schematic finally, right. Yeah,
this is like a rubber meets the road kind of portion. Yeah. And so in
the day and a half, I have about 90% of the schematic done. And so now is just like odds and ends to finish up, like putting ESD protection on on power that comes off the board and stuff like that. But one of the cool things we did was yesterday, we simulated the MOSFET drivers,
right? Because so from a lot of the mechatronics in a way you have MOSFETs that activate everything, right?
Correct? Yeah, you have basically you have n channel MOSFETs that are current sinks for pretty much everything on on a pinball machine,
right, which is like motor actuators and solenoids and things, right? Correct. Right. So each one of those MOSFETs is a pretty beefy little guy, right? That can handle the current spikes that go through everything correct. So typically, when you have MOSFETs of that characteristic that can turn on, especially given that these are all kind of like logic level goes, the you have to drive them with a with a decent amount of current. And they will draw a decent amount of current on their gates, because a lot of times they have quite a bit of capacity. That's correct. On the on the front. And so we simulated that yesterday. Yes, to try to get an idea of like, what's the worst case scenario? Also, what's the fastest you could hammer this if you wanted to? Yeah,
and we were also looking at, because the solenoids are driven off a different power supply. Then the board logic stuff, and the grounds to make sure the potentials are the same. come across a little tiny. Oh, 805 jumper on the board. And so we wanted to make sure, hey, if you were hammering all the solenoids as fast as possible, because you're basically only passing the gate current across that jumper would it heat up in smoke or something bad happened?
Well, actually. Okay, so real quick. Let's talk about that for a second. Because that's, that's really interesting. You, you have one ground on board. And not necessarily we're not talking about different ground planes. But you do have your ground kind of cut up in a way. Yeah, you know, what's your reasoning for that? Well, it
helps keep the noise from the solenoids away from all the other circuitry on the board.
Right? Because you technically have like, what three power supplies 12 five and 50.
Yes, yeah, we got three. And you really want to keep like you don't want like let's say if you put the like you took the two power supplies that are in the bottom of the cabinet, and you connected the grounds there. Well What if the MOSFET what is the one that solenoids decides? Hey, I want to return, you know, the easiest way for me to return is underneath your microcontroller, right? That's the best current ugly, lowest impedance for its return. It's like, you don't really want that to happen. So he's like, okay, even though it might not be the lowest impedance for it, you want it to go in the areas you want it to go. So it's separated for that, right?
You want to guide and steer your ground current and understand where it's going to and where it needs to return to, right. Yes, yeah. That's like, honestly, that's like half of PCB layout is understanding like, Okay, I'm spitting juice out of my power supply. It's got to come back. Where's it going to come back? That's, that's one reason why, like, just dropping a giant, zero ground plane isn't always the best option, you know? Sure. You gotta you got to think about it. Because I mean, technically your board, you could do that. Right?
That actually underneath all the other logic level stuff. That's how it is. It's only in the MOSFET solenoid section that it's separated out, because I don't want it to go over there.
Exactly. By current stuff. So it is it is one uninterrupted ground plane, but you are you are you have chopped it, basically, it's chopped. Yeah. Right. And in this kind of case, that makes sense. Well, okay, so in, in boards that have large variance between their power supplies and current levels, that makes a big difference. Yes, yes. Pretty much have to do it.
You have to do it. Yeah. And, and having basically the board be the spot where the two ground planes from the power supplies become the same potential, you reduce the issues of basically the 50 volt power supply, wanting to return through, let's say, the 12 volt actual line, not the 12 volt line, but the ground for the 12 volt line.
Right, right? Well, so I was reading a book recently about this topic. And what's interesting about it, think about this low frequency, or DC signals that are flowing through ground tend to flow more or less uniform through the ground plane. So let's say you just had a board that was a rectangle, and you had connections at both sides, right, just take the hole, it would just yeah, it would take the whole thing. So if you had a high current going through that, more or less, the ground plane would lift in voltage uniformly, right. But if you have something like a solenoid, where you turn it on, it has a huge current spike, like a very fast pulse right away, and then settles to a DC, what you'll have is it'll take a really short path through the lowest impedance section of the ground plane. And then as soon as as soon as it settles, it then spreads across the entire thing. So you get all of these really weird artifacts, if you're trying to send huge current pulses that go from fast to slow through a ground plane. And it was interesting, because I had never thought about that before. It's I always thought of it one or the other, you know, you got digital signals that have current pulses, use the ground plane, make sure you do your tracks above your return paths and like control it that way. And that makes the that makes sense. But if you have these weird pulses that end up in DC, then you got something a whole different beasts to deal with. Yep. Yeah. So it sounds like your method of dealing with it is the only place where they're connected. Will is one section that is some kind of a jumper and the only current that will flow through that is whatever drive you have to the gates Correct. That's the only thing that connects those two, correct? Yeah, and then that sounds totally reasonable.
Yeah, that's what we did on the older pin hack board and seem to be it worked pretty well. Like we never had any issues with that but we just this is one of those like, hey, let's actually just calculate this and see what it was like right and like are we going to blow up because we're changing our drivers because on the pin hack we'll use an an gates because we were basically muxing a bunch of signals together and then if they're all ones then yeah, that solenoids okay to fire basically, like the watchdog was in on the AND gates in the polls from the microcontroller was also in.
Oh, did you have like a safety function thing? Yes.
Oh, that's cool. We also have one on this board as well, what we're doing a different way that cheaper. Okay. It's actually better to it's not just an gates all over the place? No. But so 505 drivers were using can drive up to 20 milliamps, if you just hammered them, but we were like, well, let's just do them at like 50 to 60% You know, sight duty cycle, not duty cycle, current rating. Right, right. And so we limited it to 10 milliamps with a resistor and in the simulation, and then set it up how my circuits set up and then we basically set up all the you set up all the time functions, and we hit go and It's interesting because like, it will take like those those, like, if it's ideal situations, it will just take as much as you can give
it. Right? Well, so yeah, the input gate on one of these beefy MOSFETs is, is effectively a capacitor, right? Yeah. And so if you if you think of it as the 595 is a driver that goes into this capacitor, you put some series resistance in there, and then you have an RC circuit that you can generally calculate, or just simulate. Yes. And that's effectively what we did. And that series resistance that goes into the MOSFET. We did. We stepped its value until we found something that worked for about, what was it? 10 milliamps?
Yeah, I think it ended up being about 12. The 13. That's fine.
Right? Yeah. So generally 10, just for the easy sake. But yeah, so that that resistor does two things, actually, it limits and kinds of flows down things. It prevents a huge current inrush into the MOSFET. But it also squelches oscillations, and kind of like prevents the local oscillation of the MOSFET, which is incredibly.
Yeah. And I think and like the timeframe where like when you turn on the MOSFET, like, when it goes back to steady state? It was it's something that was like only like, like, it's in the pico second range,
I think. Yeah, I think from the like, the pulse going high, which we simulated, we simulated as if the driver the 595 was like, perfect. Yeah, we simulated where the 595 went up. In? Gosh, one picosecond.
No, no, we actually looked at the right time.
Oh, that's right. We change it. I'm sorry. Yeah, we change that. Well, regardless, the whole current input spike, it was 600 pico seconds. Yeah. So so it kind of, you know, it kind of did a capacitor charge charge curve up to 12 or so milliamps. And then, you know, came back down to a steady state and about 600 picoseconds, which 600 pico seconds allows for a ridiculously fast switching, which in reality, you're not going to get that but no, like
our colonel on the pin guitar. And also the pin hack runs out like 1000 hertz, which is plenty fast for a pinball machine. And, yeah, 600 pico seconds, I think it was, like 133 megahertz or something like that. And, yeah, we're never going to be able to drive these FETs even close to that speed. Right.
Right. And the so yeah, the general pulse that would get sent out by a 595 is somewhere in the range of, like, 40 milliseconds. I believe we were saying. And so yeah, that'd be plenty. No, you have what? How many was at 48 of these transits before? 24. Okay. So 24? Let me see, like, if in the random case, that all of them fired at the same time, like how much current would at peak in that curve? How much would flow across to your little ground jumper? Right? So it'd be 24 times point? Oh, 12. Right, for 12 milliamps?
Well, that's like, in one pico second.
Do you know what I'm saying? At the peak? If they all fired exactly the same time, what would be the most amount of current that would flow across that? It's 288 milliamps. So really, frankly, not that
not that much. And so we did jump, just from a like safety standpoint, we went from an o 805. To a, what was the largest size I had like a 2560 or something like that. Yeah, jumper just to be like, Okay, there's no way like, because it's supposed to have zero is not zero, though. It's like point o one. ohms. Right.
I've always loved that. Because if you go search for zero ohm jumpers, in terms of like surface mount components, they have a tolerance. And they have a power rating, which which is funny. Yeah. Tolerance is 00. Yeah, power rating on zero is zero, right dissipates nothing.
Yeah. But they just fade a little bit. And that's point oh, one ohm or whatever it is.
Right, right. Yeah. And so you have to you really have to look through the datasheet to actually get an understanding of what they mean by a tolerance on zero.
That would be interesting. Oh, man, this is goofy. If it had a lower resistance have been a trace. I wonder if that'd be possible. Because if it was thicker, it would have lower resistance.
Yeah. However, the resistance of two solder junctions is always going to blow that going higher than the copper. Yeah, guaranteed. Solder. You know, people probably slaughter me for saying solder is actually not that fantastic of a conductor. It's just It works really well for what we need it to do.
They worked well enough for conductivity. And it's easy to assemble.
Exactly, exactly. It works. It does the manufacturing thing really, really well. But it's it's not ideal in terms of, well, and a lot of times it's like inside of ICs. That's why you have the gold bonding and things like that. It's a lot better than soldering things. So, yeah, guaranteed, I shouldn't say guaranteed, but almost guaranteed a just a trace connecting a big fat hamburger trace would, would work well for that.
Yeah. But this is so that we can pop it off. And we can put a ferrite bead, if we have noise problems. That's what will help why we did it on the pin. Heck, we never had noise problems. So always say there's a jumper. We're going to stick with the jumper. We just made it a big jumper this time. Right? Yeah. And then to do because we're going to surface mount FETs for everything. Woohoo, because that was a big cost driver on Pinnick. Like, you're talking like 30 to 35 bucks was spent on assembling thermal.
Right, just superficialis transistors everywhere, like all around the edge.
Yeah. So these are, these are all the MOSFETs that are driving everything. We're not driving, thinking all the things you should say. And what really fails on pinball machines, when stuff starts getting grimy and stuff, what happens is that coils start to heat up. And they start to basically kill their their flyback diode. And when they kill the flyback diode, when the solenoid turns on the MOSFET turns on, now it's got a straight short, instead of the coil, the inductance in the in the impedance of the coil to go through. So your MOSFETs are starting to heat up a lot. And so what we're going to do with this current sensor is be able to test basically the machines, outputs from the board. And so we can say, hey, something's wrong here. It should go into service. Right?
So what are the are all the flyback diodes on the board? Or shouldn't they be right next to the coil? We put
them on the coil. Okay, there's some manufacturers out there that do put them on the board. Because it's technically cheaper to do it that way. But it squelches better right next to the coil.
That's where it's supposed to be keep it local to the coil, and then the and then there's no chance of issues or I shouldn't say no, there's less chance. Yeah.
So what happens is, eventually those diodes just die, or a coil wears out or something like that. Yeah, and you're pulling more power than you're expecting, and then your MOSFET heats up. And let's say it gets stuck on, then. So the great thing actually about using surface mount MOSFETs is if we ignored it, it would reflow itself and just pop off the board.
Because obviously that meant mount the boards such as gravity would just pull it right off. Pull the
MOSFET right off, right? Yeah, yeah, there you go. Because I've actually seen that before on other PCBs just playing around like seeing, like, can you actually like melt? MOSFET? No, just the solders itself first.
What? What package are these? Are they deep packs?
They're Deepak twos. Okay. So they're beefy guys. And then we'll have a lot of heatsinking just in case, we're actually going to be dual loading them. So what there'll be MOSFETs on both sides of the board. Okay. Just because the they take up more space than a normal to 220. Right, because I'm staying vertical. So yeah, it's getting there. There's also something else I wanted to mention that you reminded me. I can't remember anymore.
So yeah, so the particular MOSFETs that you got, what are the rated up to something like 35 amps? What's the what's the normal? Like, what what kind of amperage can you expect?
So it's fused with slow blow fuses to nine amps total. So it actually has three, three amp fuses, because we split basically because there's 24 of them, we split into banks of eight. And so each one is on a three amps low blow. So, yeah, that's usually normal. Like, have you fired all the solenoids at once? You'd probably would blow a fuse. Yeah, but you don't do that.
Yeah, there's not a situation where that happened, right? Or not an intended central knowledge and in situation. Okay, so how does a flipper work? Is it just a solenoid? They
would like a plunger that actually has two solenoids in it oh one for open and close? No, it has a spring spring flip down. So spring return I should say. But it actually has a actually has a switch to in it. So when you press the button, it sends a signal to the parent All right, and then the pinto goes fire left flipper. And then that signal you know it turns the MOSFET on and then it so then it activates so annoyed and the flipper will flip. But then when it hits a, we have what's called an End Stroke switch, when it hits the end of stroke switch dependent or goes, Oh, you hit the stroke, and then it turns off one of the, or turns off. Yeah, turns off the high current coil, then just keeps a low current hold. It's called a hold coil. But it's wrapped in the same coil, there's basically two windings.
Okay, so one's there for the for the real hard snap to get to throw the ball. And the other one said to just basically keep the flipper up.
Yes, because you can, because that's in a pinball machine. That's really the only solenoids that are activated for longer than, like, 10 milliseconds, like a pop bumper is like 10 to 15 milliseconds,
right? Because it just got to smack the ball. Yeah, it just pops, right.
So this could be, you know, 10 to 15 milliseconds for the full activation to hit the hit in the stroke. But then when you hold it, you can hold it there forever, and it won't burn a coil and you don't want to burn the cord out. So you have a low hold current.
Okay, so the high current coil, the initial flak coil, how much current is that going to pull?
I think they pull. You know, I don't know what the actual number is. I haven't actually put a meter on it. Because I bet you the instantaneous is a lot higher than the whole new year like steady state of that coil.
Yeah, probably also, I would guess. It's somewhat temperature dependent.
I would say theoretically, if it was an ideal coil, it's infinite at time zero.
Yeah, sure. That was my answer. Yeah. Good one there.
So and then I been working more on the Doom should he add on the hardware repro is all put together. It's not public yet. I know. I said I was gonna make it public last week. But I still, you know, I've been working on penetrator more. In the software repo part is next. I've been building detailed instructions for the build environment, because I want to basically make sure a drunk person at DEF CON can build the environment that they need to like, code this thing. It will come with software on it, but you can change it. So nice.
You know, I have to admit, I'm super jealous. Because I think you have sort of an engineers like dream vacation, where you take a week off of work to go somewhere else, and work on your own projects. Yeah. That sounds fantastic. And I know, I know, my wife would not be down for that. She'd been you know, it'd be something where it's like, let's go here and hang out. And I'm like, oh, let's go somewhere where I can work on something.
Or go to my basement? Yeah, that
sounds really great. No, I mean, I would, I would, gosh, I would love to take a vacation to someone else's basement and work. That's what I'm doing. Yeah, exactly. I think that sounds like a great vacation. And love my wife. I'm putting it that way. I know. I think it's, you know, regular vacation is fun, but like I don't? Yeah, a work vacation would be really cool.
It's been nice so far. Yeah. Cool. And what did I bring you as a party or not a parting gift, a gift for letting me stay at your house.
You brought me something that kind of makes me mad. So a few weeks ago, we were talking about this 3d printed Fredman clip that I purchased from I can't remember the name of the company but out and well it's probably Fredman out in Canada and W Wilkinson audio that's Yeah, yeah. Wilkinson audio Fredman clip, which is a clip that holds two microphones at a 45 degree angles such that you can do a particular recording technique that cancels phase phase. And basically what it does is it just removes nasty hiss and fuzz from your recording. You record what two microphones and so I purchased this clip and you know, I was not particularly thrilled with it. And Parker, like in in during a podcast Yeah, he found the STL and started printing it Yeah, he found an STL from a complete Rando and printed the clip and what what really pisses me off about it is Parker's clip looks awesome. Like it's really well done. It's printed in black, but polycarb it's polycarbonate. Yeah. Polycarbonate and you use a
point 2.2 millimeter print height. Yeah, yeah. Okay, so
I'm holding both of these clips right now and the Wilkinson audio clip. It's, I mean, I've actually used it, it's totally functional and it's great. I paid 20 bucks for it. It's really thick, very obviously fast print. Material, whereas Parker's is it looks really clean in really Nice. And we actually took two of my mics. In fact, I'm clipping them on right now. And it does a perfectly good job of holding them. And it's just one of those things where it's like, you know, like Parker's it's funny because Parker's even looks more professional than the other one. You know, it actually, if I, if I had originally received Parker's print as opposed to this other one, I probably wouldn't have even talked about it. I'd been like, Oh, it's 3d printed. That's fine. It looks good. You know. But ya know, these ones are a little, little off. The one thing though it doesn't. So I don't actually have two sm 57. mics, which is that's what this is intended for. So I'm using an SM 57 and an SM 58, which some of the people in our Slack channel have pointed out, they're actually the same mic just with a slightly different cap. Well, yeah, slightly different body, but also cap on the on the top. It's the same sensing element. But since this is intended for to SM 50, sevens, they don't have the same body. This clip doesn't hold them. Absolutely, perfectly. Yeah. Whereas the Wilkinson, because it actually the clipping mechanism is on a different axis. It actually does hold it slightly better. So I would say maybe that's a win in that department. But
both of you put 250 sevens and that would be fine,
right? Yeah. If I had 250 sevens, the one you printed would be great. So one of these days when I have an extra 100 bucks lying around, I'll grab a second 57. But yeah, so thank you for bringing that. Yeah, that was? I don't know. That's cool. I actually have some recordings to do. So I might, I might try your clip on this on those. So
I'd like to hear them. For sure. And so one of the projects that we wanted to do when we when I came up here for vacation was the text adventure game.
Right, which we came up with, gosh, few months ago. Yeah, a few months ago at this point. So you want to give a quick description of what the project was for those who haven't. Yeah, so
the text adventure game is going to be a USB serial dongle that you plug into your computer, it has a URL, you'll have a you have the terminal into it. And it will be like a text adventure like Zork, the old video game. And so we want to use some of the hardware aspects because the fact that we actually have hardware so we can do speakers or we can do lights and stuff like that. The cool thing is Mouser electronics is going to be sponsoring this project. That's right. Thank you Mazur. Yeah. Thank you. Mouser. And so yeah, so Steve and I went to a bar after a barbecue with it was
Danny, Danny, Danny Rankin, which was episode one. 170 something. Yeah. 170 something. The one the mayonnaise, drone and other war crimes? Yes. Go check him out, is actually kind of funny because Parker was coming up. And then Danny was like, I've got a barbecue at my house. I was like, well, Parker's come into that.
So after that, we went to a bar. Yeah. And drink. Lots of beers,
lots of beers. You know, it's funny, because we were kind of mentioning it. We've had a couple of months that we could have worked on this project. But a long time ago, we said, why don't we just work on it when you come up? Because it's working on a project like this, where you have to be a little bit creative, as opposed to just like rigid and hard. And with design, it's really hard to like, log in over Google Chat and like, be creative on that. So we just said, Let's go to a bar. Let's sit down and write down a bunch of stuff. And we were super productive.
Yes, it was a lot of fun. We actually, we pretty much wrote the main characters. Yep. We wrote the general story and general story, the beginning and we still got to fill in the middle gaps a bit. But it's going to be we changed it a bit from our initial conception from like, 10 podcasts ago. Yeah. So it's gonna be more mystery. Yeah. And a little bit of horror in it.
Yeah. Yeah. And there's going to be there's going to be a lot of discovery. You know, because it's Parker and I there will be plenty of easter eggs. Yeah, probably a lot of easter eggs that you won't even know our Easter eggs just because like, we were drinking a bunch of beer, and we're like, oh, we should throw that in there.
We have we have a list of like, things we just want in it. Yeah. What's the list name?
There's no let me let me turn to that page. I wrote it on the game flavor. Yeah,
we called the game flavor.
I have like two pages of just flavor that that we're writing in there. Until honestly, the way I kind of want this to be is where anyone who gets one of these dongles and plays our game. I want them to just be like, ah, yeah, that's cool. Like as they played through it. I don't know. I think that'd be a ton of fun. So we've got some pretty, like, we're trying to rope in as much as possible. Like there's a bit of meta around this game. Yeah, I
would say it's pretty much it. Yeah, meta and in kind of like the pop culture that Steven and I grew up with. Yeah. And because we, a lot of the stuff we've actually watched is the same, but there's a lot of stuff we like done separately. So a lot of that stuff is in this, because it's not going to have like everything. Like, like I would say, like, some pop culture stuff like make sure it does like Ghostbusters, it makes sure it does X and Y. It's like, No, this
is just stuff that Steve and I been exposed to right, you get to see, it'll take a quick little glance inside of our messed up minds and see all the weird stuff we like from when we were younger, all the way up till now. And so there's a bunch of different locations to visit in this game. Well, I don't know, maybe not a bunch. But there's, there's plenty of unique locations. There's some RPG elements. There's a small amount of randomness that goes into this
won't be any game mechanics. That's random. No, no.
In fact, we kind of discussed that. Because I think we even had this as an RFP at one point in time. Zork, the original Zork game had randomness to
when you picked up an item, it would randomize the weight, right? It actually there was a number for it. It basically would randomize if you could put it in the inventory or not. I would say it's not because of the weight, it would just basically randomize. If you could put it in your inventory. And if you failed, it would say it was too heavy. Whereas if you just tried it again.
Yeah, but but but there was no it didn't convey that to the player who said you can't put an inventory. It's too heavy. Yeah, so you just trust the game? Yeah, it was it was very much trollee It was super trollee. We we are incredibly against that though. The one thing I don't want to ever do with this game is like leave you the player saying, What do I do? Where do I go? How
do I do that? Or that's BS? Yeah, I
hate that. I hate that. So we're not going to troll you at all. Like, the the parts. Like if you if you get past a section, we want you to feel like I conquered that section. You know, like my wit or my smarts.
So I'm gonna take a look at the notes because I actually haven't looked at them since like, oh, well, yeah. Okay, so when you get to see my bear writing, I just want to pick out one and read it. Okay, something else.
It's multiple pages. Right now, though. Yeah, it's gonna be I don't know, it's gonna be really cool. Hopefully, there's elements of every part of the game that need to be activated.
Oh, so yeah, I'll say right here is the the, because you're a detective or your characters. Detective. Yep. And he's a robot, right. And his serial number is D 373. C 7153. So it's stuff like that. That's a little bit of the flavor text,
so to speak. There's yeah, there's a lot of
we actually did write a lot. We were only there for two hours.
No, we were there for longer than, yeah, my work. But we were my wife was at the barbecue with us. And she just, she had a play to go to in a different city. So she took the car, and we walked across the street to the brewery. And then she came and picked us up way later that night. And all we did was work on this game. Yeah, really worked until the sun went down. And then we couldn't read it read like, down anymore. Right? That you know, and that's that's a really good thing. All I had was a purple pen. And at twilight, if you're writing in purple, you can't see any can't read it. Yeah. So learn from my mistake on now.
Yeah, so the way we're gonna do a little location. Spoil. Oh, yeah, you're spoiled. So it's you. It's a space station. And it's a force spoke space station. So one is like the landing dock that you arrive at? And the center is it's like a shopping mall. Yep. Yes. Shopping Mall and space basically.
Right. So yeah, yeah. Like think of think of a shopping mall with four spokes hanging.
protruding out of it. Correct. And we're gonna call it the conservatory. That's right. Mall food court.
So, you know, a lot of the details about how the game is going to come alive. I mean, this that's still to be worked out. But you know, to kind of reiterate
Oh, yeah, the our stats, the RPG Oh, yeah, because it's robot, our readiness, oh, observance, which is perception. readiness is dexterity. Beauty is charisma. So it's our OB the next Oh is offense, which is your strength and T is tenacity which is your constitution. I love it.
Yeah, okay. So he let's let's boil it down. I know we've talked about it but just do To kind of dispel confusion, basically we're making a USB stick that you will be able to get somehow I, we haven't figured that out yet. You being anyone, and you take this USB stick, you plug it into your computer and you serial terminal into it. And the game starts, then. Good luck.
Yes, it will not have saving, right. So when it powers off, you lose your game. But it's not going to be like a game that takes 10 hours. I'm hoping like you can do it in a sitting, like maybe an hour and a half an hour ish.
Yeah, yeah, we we were thinking, if you haven't played the game at all, and you don't know any of the puzzles, and you're discovering everything, part two, three hours, two to three hours is what we're kind of shooting for. If you've played the game before, and you want to do some more exploration or whatnot, maybe like 30 minutes to an hour or something. So that's kind of cross our fingers. My wife is an avid mystery reader. So we're going to give her the story. And she's going to tell us that we did a lot of dumb things, and she's going to rewrite some chunks of it and help us out to make a cohesive story. But but we do have the beginning. In the end, we know those two things,
we call them states, we have a beginning state.
Because technically, these will be states inside the
yeah, there's actually going to be like what runs this whole game is gonna be a ginormous state machine. Right, right.
So actually, you know, I don't think we've talked about this, are we going to publish this and publishes as in like, the first code ever?
Yeah, I think we'll probably release it. And just I think it would just have the hardware open source stuff as well. Yeah. So people can build it and just provide a hex file. And then maybe, like six months down the road, and people have actually had a chance to play and stuff, we will release the source code.
Yeah, like that. Yeah. Yeah. That's that. That's, that's good. Cool. That'll be fun. So keep it neat. Keep your eyes open for that. We, we made huge strides. So the sort of the next step with that is kind of cleaning up the story. But now that we have like, what we want to have happen.
Yeah, the next day, we need to start making the hardware. Yeah, though, the next step is to clean up the story, make it all flushed out and then build a map based off the story, right? Because we just have like an overview of like, these are the areas you can go to right. But like in those areas is gonna be rooms and passageways.
Yeah. Yeah. So far, we have four areas. And the game would be boring if you had to just travel between four areas. Yeah, we need to make that a little bit thicker. Yes.
And then, then once that's done, then we can do hardware, because in reality, the hardware is going to be fairly simple and what we put on it, like the what the flavor hardware, exactly the flavor of hardware is Gasby. Derived from what from the story? I don't want to put something on the board and be like, we have to work that in.
No, no, no, no, it has to go the other direction. Yes. But the board has to reference the game. Yes. Yeah. The board has to bring its flavor to the game, and potentially be important to the game. Yeah, that's
it's like, why can't you just make this a, you know, a C program? And you just say, like, an exe, right?
Yeah. The whole the whole point. Is that like we're providing a unique hardware experience. Yes. Where like, this is a random stick. You plug it into your computer, and there's a whole world inside that stuff. Yeah. And the hardware is part of it. Yeah, yeah, exactly.
So that's gonna be fun. So basically, hopefully, by the end of my vacation, we have, basically all the way to like, now we need new hardware.
Yeah, yeah. Yeah. And we have a good handful of days left. So yeah, we can we can knock that out. Maybe we would go to another bar.
Once a night. I'm cooking pizza from scratch. And while I'm doing that, we're going to be flushing out the story more.
Yep. Yep. So the ortho rapid fire opinion. Yes. So these are
really weird. Our photos this week, mainly because since I've not been really working. I haven't been like scouring Twitter or anything like that for our foes. But this one really cool tweet by I don't think he made this but it's nameless, nameless TV. He posted a cheeseburger wind tunnel test. And the first thing I thought of so go click on link guys, and it's pretty funny looking. But first thing I thought it was McDonald's is making sure that cheeseburgers can go down your throat as fast as possible. So you eat more
right? Yeah, you buy another cheeseburger right away hungry? Yeah.
I think it's only going I think the gift says it's only going point 05 marks. How fast is that?
Google that? Yeah, I mean, honestly, out of out of everything. The McDonald's cheeseburger might be the highest engineered food out there
could be is only going 38.3 miles per hour or in non freedom units 61.74 kilometers per hour. It's July 4 week
the funny thing is like
you know, so it's like fourth week you know what else happened this week?
Was that the boy Canada Day?
No the US women's national soccer team beat the England team today. So we have a two losses by England. We're gonna lose all our English
back to back only 300 years
back on topic Yeah, only going what? 38 miles per hour.
Well, when was the last time you saw cheeseburger go in 13
Um, awesome. Eight one
that's, that's great. I wonder how much lift
the bun provides?
I'm sure they're measuring it because in this image it's like legit in a wind tunnel a wind tunnel Yeah, and I guarantee you they're apparatus like
mad wonder if different condiments have different like coefficient of frictions to keep the bun on
What's What's so weird about this is like you look at it in the cheeseburgers like perfectly still. Yeah, so you probably go faster. Yeah, it does. I mean, okay, so obviously has a boatload of turbulence behind it. But the the leading edge of the cheeseburger looks very similar to an airplane wing in the tunnel. Yes, it's
Laminar calm condiments. And so why did why are the the streams not like yellow and red like the
former don'ts? No, no,
no to have like ketchup and mustard streams. Oh.
yeah. Yeah, so I found actually found a different Well, I found how do you pronounce this? I am G you are injured injure? Is that how everyone? Like?
I've never even talked to anyone about it. It's like people who are going to email us that I said GIF wrong.
You did not say GIF wrong, because that's how GIF is pronounced? Well, I've found a I've been a ninja that has the wind tunnel cheeseburger. But they also have apparently somebody put a mock model of a Millennium Falcon in a wind tunnel. And surprisingly well, they took it up to Mach three. Really, which is, which is a hell of a lot faster than the cheeseburger that's for sure. And you know, I have no clue how to read a wind tunnel diagram. However, it is next to something that is supposedly aerodynamic and apparently the Millennium Falcon is not terribly an aerodynamic. I mean, I'm sure like, it has all kinds of like, bits glued to it.
Yeah, like the satellite dish and stuff like would the satellite dish in real life even hold up to Mach three? In like, one out this fear.
No, I guarantee you not. Yeah. What is Mach three in freedom units?
Fast. 2301 miles an hour. Wow. Yeah, that's fast.
That's what we've asked. I saw something the other day. That was like, Freedom units. However ammunition is in millimeters.
Some ammo is Yeah,
most ammo. It's right.
Not 30 yards point three. Oh,
right. But handgun ammo. Oh, well. Yeah, say some is some
son. Sounds nine millimeters. 10 millimeter. That's 45 which is a handgun ammo, right. So 45 is a Imperial measurement. So
45 is point four five inch? Yeah. Easy. Very easy, right? Easier than nine, eight?
Sure. I like the metric system a little bit better. Yeah,
I think we should I think we should migrate?
Yes. Except for woodworking.
Why Woodworking is like where it's awful.
No, the imperial system? Because you can't buy metric anything cut. What do you mean? Like you buy a four foot by eight foot piece of plywood. Or you just buy the equivalent but it's going to be like three it's going to be like some decimal in metric.
Oh, you will. I would switch over to measuring so go round to the nearest millimeter you'll be fine.
Yeah, probably I think we've had this discussion before. It's like, they should use all the units in metric. Like we need dekha meters.
Well, I mean, you've been over this a couple of times, like, Isn't that how it's intended to be? Yeah, but people
just use centimeters, millimeters and meters.
Honestly, I kilometers, like, from what I've found, is use millimeters and meters like centimeters are also used, but not as much, you know. Because, especially in what I've, I've seen in my industry, like, you'll see things in the multi 100 millimeters. It's like, well, you could have gotten centimeters, but they people just don't.
Yeah, I think basically, people pick the like, there's someone long time ago or group of people a long time ago, pick like, these, like four or five are the ones that we're going to stick with. And so people don't have to learn 20 or 30, or whatever. How many there are. All the prefixes. Yeah, I mean, it's like, when I see like a call out for like a one nano farad cap and I'm like, Nah, I gotta figure out what what the pic and the Mauser drop down. Oh, really? doesn't do it. nanometre manifests? I don't think
now they do micro, they do pico micro. They do milli. Yeah, there's Milli and fair ad, which they basically the one they don't do is nano. Which I use nano all the time. I actually. So like, in a lot of my stuff. I like to take a 10 nano farad cap. I like 10 nano farad as opposed to point o one, Mike was asked do you
like 100 Nano threads? Or do you like point one microfarad.
Usually, I like to go with nano farad. And the reason why I do even though I don't do it at work, because our standard is not to do that. My impersonal stuff, I like to write out 100 nano farad. The reason why is because having a decimal in the value I've found can be a little bit confusing, especially if you print it on the silkscreen if you ever need to do that on Oh, yeah, because it can be harder to read 100 nano farad is a lot easier and bigger to print than a single dot. And that gets confused because that
dot could be under your minimal screen size. Right, which like no EDA tool. Does. DRC check on.
No, I don't care about Yeah. And then and then if the decimal gets gets missed, then you get something that says like 01. You and then that's really confusing microphone. Right. Right, then that's really confusing. So that's why I typically go with I'll, I'll stick to the notation of P N. You um, f is that's what it is. Right? Yes. Yeah. And then I said that, did you? Yeah,
I reiterated it.
Yeah, there we go. Actually, here's, here's a question for you. When you write values for resistors, do you do lowercase or capital K? capital K? Okay. I almost always use lower. I just, I know. It's just a thing. No, I do communist. I don't know. Like, that's a lot of stuff. It's funny. Hat going from
do you spell cathode with a que?
Sometimes? Yes. Actually, sometimes. And technically, there's situations where that's correct. Well, it depends on what country you're in. It depends on what country it also depends on what you're referencing. The ancient Greek of photos was actually the word that that came from. And that starts Okay, talked about that. Yeah. Yeah. Okay. Yeah. So sometimes it makes sense to do that. Sometimes it doesn't. The wolves are going Oh, yeah. Like, it's funny, because you don't really think about this stuff a lot of times, especially if you're just like a hermit in your basement, Oregon. But switching over from working at macro fab and coming up here and working for a completely different engineering firm. Like this kind of stuff, you start to clash. As soon as you start dealing with multiple engineers, you have to start asking these questions where it's like, do we use N? Or do we only use you? Do we do lowercase or capital K? Like because we want all of our products to be unified, you know, you want everything look? Right, right? So you have to, you know, there's a style guide that you kind of have to create with this kind of stuff. That was a tangent. Yep. From cheeseburgers to style guides, yes.
And everything in between.
So the next topic we have in the RFO. I put this on here because I'm going to say this is like thumbs up. This is what you do with a 3d printer, or a really great example of what to do with a 3d printer. This is an article I found on Hackaday called wire Bender aims to take circuit sculptures to the next level. And basically what it is is just a demonstration of a guy who built a automatic wire bending machine almost entirely out of 3d printed brackets and, and like that. It's really cool. It's really cool. It's like a little nema 17 stepper motor with some extra accoutrement that goes with it. And it's it's a pretty cool little wire Bender that I would assume is programmable fully. This is something I've been wanting to make for a long time myself but eventually will happen or not happen. But the the work that the guy did with 3d printing is beautiful in my opinion and it's it's a really great example of like, here's a stepping stone from I have an idea and I want something to be finished. I can make really rigid and solid like pieces 3d printed. And I think this guy could really take most of those pieces with a little bit of, you know, optimization, he could make them machinable and turn it into a real wire Bender that wouldn't wear out. You know, the problem with a wire Bender like this is the bending anvil and the teeth
as I say You call that a Mandal or an anvil?
I've always heard it been called anvil. Okay, so
the anvil is 3d printed as well. And I was looking at the video on like, that's probably the what will wear out?
Well, it'll wear out really fast. Maybe not really, but generally pretty fast. If that was made of aluminum, it would still wear Yeah,
and you know, hardened steel.
Yeah, exactly. But
3d print that yet.
Not Not yet. But we're getting there. I've seen some some pretty cool stuff recently. But this, this will, this is so great. Like this is where 3d printers I think Excel, like you have an idea. You can crap it out real fast, you can test it. And then you take that and you go to the next level is machine and make it out of something more rigid. So I just wanted to showcase that because I know we've been kind of shitting on 3d printed stuff. And I want to say like, thumbs up. This is good stuff. I want to see more of this.
So our next topic is it's not really a topic either. This is weird. It's weird. It's an apparatus for facilitating the birth of a child by centrifugal force. And it's a patent image.
Parker just randomly sent me this on Slack. Like it was a random Reddit post. And I was like, What's this? I click on it. I'm like, Oh, good, Lord, what the hell is?
So my only question. I guess I need to sit down and read the actual patent like the words and is that just the picture? But where does the baby go?
Okay, well, let's first let's just do a random, random, let's describe this real quick.
So it's a thing. It's a hospital bed. And it's in a circular room, and it spins.
And you you place a woman on one of the the edge of this bed that spins around the room think of like, it's like the astronaut testing facility. Yeah. Where they spin around. It's been around for. I mean, that's not the point. But but they do. Ever you see. Yeah, you see that happens. So I mean, like, I guess the the idea of this pattern was if you position a pregnant woman correctly, and then you spin around, you can aid birthday. Yeah. But yeah, you bring up a really good question. Does the doctor himself sit at the end of this table? Oh, and he's gonna spin around as well. Yeah. So so he can catch the
eye. Like your idea, though, is like if there's like 40 people with catcher mitts? Yeah, we
catch up. And they're all in a circle around the room. Yeah. And you all place bets, who's really gonna catch? Honestly, have you ever? Have you ever just gone to Google patent search? And just like, cruised for a little bit? No, I haven't. It's fun, because you'll find random crap like this. I mean, the patent, US Patent Office is not particularly picky about things like if you want to patent this, you can like, it's just takes money and time and effort, you know. So that it doesn't, it really doesn't mean that you're going to get anything out of it. It just means that you have a piece of paper saying you thought of
this thing. When I was first,
I was first to think of an apparatus for facilitating the birth of a child by centrifugal force. So
I've got a question. And this is also a question for our listeners for our Slack channel, is if you could design something that would operate by using centrifugal force, what would it be?
Ah, I might design something. Let's see here. i Okay, so something that would you would load your toothpaste tube and into or take it out and it would take Yeah, you would get 100% of the pace data.
I was thinking catch up. That's good to mustard. It just spun it around. But then I'm like, if you'd basically would probably even make you'd have to make it Your circles back to the cheeseburger win test because you get, you'd have to figure out how fast your cheeseburger could go. So you can figure out the max speed of your rotational. When you're, you put your mustard container right in the in the surgical device, right? Yeah, it spins. And then the cheeseburgers on one end. Yeah, it's the doctor with the glove. And that spins. And but you can't go too fast with the burger will fly apart.
Right? You want to deposit the right amount of condiment? Yes. Onto the burger. Right? That I like that. Yeah, that makes sense.
Totally work. That'd be a very good entry to the Useless Machine Project contest.
That would be which we have had a couple more entries. So it's starting to pick up now, which is pretty awesome. Actually. Okay, so the Heinz 57 ketchup bottle. I actually saw this on Gosh, I don't remember where it was a while ago. But you know how the, the glass bottles like ketchup get stuck in when you like, hit the end of it? Well, okay, the little embossed area, that's 57. Okay. Apparently, that is the optimal place to tap the bottle to make stuff come out. And they put it there on purpose. So you hit the 57. And that that's like the perfect spot. Which is interesting. But so ketchup is a non newtonian fluid. So the thing about it is like, once you get it flowing, it wants to flow, but it's hard to get it to flow. Right? Yeah. So something about that one particular area is like, you know, tap there,
probably some residents or something like that, and the glass bottle, hot
burger tips from the mecca of engineering.
So what would you our listeners designed and for that uses typical force, we'd like to know.
Yeah, Mac fab. That's like, Yeah, that's right. Yep. Join up in let us know. Yep.
And I think that will end this podcast. I
think it will, too. Yeah.
So that was the macro engineering podcast. We're your hosts, Parker Dolan
and Steven, Greg will let everyone take it easy. Thank you,
yes, you our listener for downloading our show. If you have a cool idea, project or topic, let Stephen I know or a way to utilize centrifugal force in a useful or useless manner. Tweet us at macro fab at Longhorn engineer with no O's or at analog E and G, or email us at podcasts at Mack fab.com. Also, check out our Slack channel. If you're not subscribed to the podcast yet, click that subscribe button. That way you get the latest episode right when it releases and please review us wherever you listen as it helps the show stay visible and helps new listeners find us
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