Mach 5 Sandpaper – MIT Rocket Team

Welcome to the macro fat engineering podcast everyone. We are your guests, Luca COVID ich and Charlie Garcia. And also joining us are your hosts Parker, Dolman and Steven Craig. This is episode 195.

Thank you so much for introducing us. So what? Yeah, what are we going to be talking about today look, and

so Luca and I are here from the MIT rocket team. We design build and launch experimental, high powered sounding rockets. And we're developing the technology to help democratize access to space.

So let me go ahead and read your BIOS real quick just so we can give a little bit of a background here. So Luca is a 20 year old sophomore from Slovenia majoring in electrical engineering and computer science. Luca joined the MIT rocket team last fall and has been the leader of the avionics of team since July. He's also part of the MIT varsity soccer team. In his free time he likes to play frisbee, drums and compose music. Charlie attended space camp as a kid every year he could. He became one of the counselors, Charlie enjoys sharing his love of space exploration with people of all ages, and walks of life through various mediums. In 2018, he led the MIT rocket team as President to launch the project Hermes to 20 32,400 feet. Now, as the publicity Chair of the MIT rocket team, Charlie hopes to inspire others to explore the heavens.

When Charlie isn't building rockets, he's using his telescope, tinkering with his 3d printer or enjoying a fantasy novel.

So thank you, Luca, and Charlie for introducing the podcast. And Steven and I,

you guys are the first guests who have ever introduced us.

I aim to please

shoot for the heavens, right.

So guys, what is the MIT rocket team besides the obvious of it, being from MIT and being rock rockets, and it being a team?

Well, the rocket team is really a student engineering group. And it's, it's kind of changed forms a lot. It's almost 25 years old now, which is kind of crazy to think about. And really what it is, is, it's a way to bring hands on engineering experience to the students at MIT, MIT, delivers a very, very incredible theoretical education. But that education is kind of wasted unless you can apply it. The MIT motto is men's mottos, which means mind enhance. And MIT our classes cover the mind part pretty effectively. And on the rocket team. Our goal is to give our student engineers the hands part of the the MIT experience.

I see that on this podcast, I will also learn something about the history of rocketry myself. But yeah, our our goals are, we have pre pre, how to say precisely set goals. The first goal is to teach people engineering skills to get them jobs in aerospace engineering. The second goal is to launch fully student builds rockets to space. And then our third goal is to publicize rocket science and through various outreach programs, and get more people excited and involved with rocketry.

Cool. So what is what is your current projects right now?

So we've got we've got kind of three ongoing projects at the moment. We have project Hermes project, Hermes is on its third rocket project. Hermes, is goals originally were to develop rocket team technology necessary to fly a rocket to approximately 100,000 feet. And so then our second project we've got going on, it's called staging demonstrator. The staging demonstrators goal is to develop the technology necessary to fly multistage rockets. And then our third project is kind of a little unrelated to the first two, it's building a five propellant liquid rocket engine. liquid rocket engines are more complicated, more efficient and more powerful than solid rocket engines, and they scale better, but they are they're really a pain in the butt to develop. So we're kind of working on all three of these projects in support of our ultimate goal, which is Luca mentioned, is to go to space to launch a rocket to space, an entirely student built rocket. So project Hermes is supposed to be the first stage of our spaceflight. That is the large booster rocket that carries a smaller, more efficient rocket to a high altitude and high velocity, staging demonstrators developing the critical technologies we need for that two stage rocket staging rockets is a really challenging exercise and if you do it wrong, it you know can break both stages. So you SpaceX actually has failed a couple of flights because of staging difficulties. You know, staging difficulties or real like failing to stage causes a lot of rocket failures as well. And then of course, liquid engine is just kind of a long future outwork projects that if we develop that technology on the team, then we have that as a resource we can use to build future rockets that don't just use solid rockets, but also can be liquid powered, which are both more controllable and more powerful.

So you were mentioning about solid rockets and staging, so your staging rocket is going to be all solid state. That's correct. So the solid state's the wrong word, solid fuel,

solid fuel. Yep. So the MIT rocket team has some of the largest student built solid rockets in the country. I think, last time I checked the only university with a larger rocket that ours was USC. And they do have a seven year headstart on this. And they're they're brilliant, awesome engineers. So I'm totally okay. Having to wait a couple of years before we can claim that title. But we really have worked hard to develop some really large rocket technology using solids.

So and also you said, I think actually it was Steven in the bio is, so 32,000 feet is not the space then.

No spaces 330,000 feet,

okay? Or magnitude more.

1. How many miles? Is it? 6062 and a half miles?

Yep. You got it, Stephen.

Cool. So what's the challenges then for staging? Like, I guess kind of got to explain what staging is for people as well.

Right? So briefly, staging as a concept is important in rocketry, because in rockets, it doesn't actually matter how much fuel you bring with you, it matters what percentage of your rocket is fuel. So that means that a rocket that is 50% fuel will go just as far regardless of if it weighs a million pounds on the launch pad, or 10 pounds on the launch pad. So what staging lets you do is staging lets you drop unused mass, right. So especially with solid rocket motors, you have this big heavy case that holds all of your solid rocket propellant. And once you burn the solid rocket pellets out of it, all of that case, weight is no longer useful. So by having a two stage rocket, it gives you an opportunity to shed weight and reduce the total weight of your vehicle so you get more bang for your buck for your remaining fuel. But of course, this has lots of challenges both from a mechanical and a controls perspective, you need to hold the rockets together very securely through Mach three flight before you stage them, they will reach a higher ultimate speed. So you need to have the thermal protection systems necessary to protect all the components. And then also and Luca is more qualified to speak about these the control problems, right? When is it appropriate to stage and also, if you stage incorrectly, you can create a very hazardous situation for people on the ground. So you know, you look do you wanna, you wanna talk about all the work we have to do to do to figure out when we can and whether we should stage,

I guess you would also create a hazard situation for birds.

I don't think we're that concerned about birds. There's many more, more dangerous things to think about. Yeah, but definitely, we do not intend to hurt any animals.

Just we're very sorry to any birds, we may or may not hit on the way up and we appreciate their sacrifice for the good of all of humankind in our endeavor to reach space. We will mourn their loss and tragically pushed forward to honor their memory.

Exactly. That was that was an excellent

save. Yeah,

we are we are also launching in the desert. So there is not many birds in our way. So for all the bird lovers, you know,

where do you launch at?

So this year we launched in the Mojave? Yeah, the Mojave Desert in California,

we've discovered a special breed of suicidal Jack Rabbit a couple of years ago on our way to a launch. We have really good drivers. I mean, like, you know, we take care of people who are responsible and good at driving the cars. And we're heading out to the launch site and about 4am and we're driving out and all of a sudden, out of nowhere, these bunny rabbits start jumping into the middle of the road, like directly in front of our car. It was awful. They were like they were attacking our car and like die. And we thought it was just our car like our drivers like traumatized and she's like, Oh my god, I'm so sorry. I'm killing all of the bloody rabbits. And we get out in the driver of the car in front of us is like oh my god new bunny high score.

We were talking we were talking about getting potentially demonetized if you had YouTube videos, I feel like that's something that could get you demonetized right there. The bunny, bunny Apocalypse

we felt so bad. I mean, we weren't do anything. It was either the sound or I don't know it's something something about the cars was confusing the bunnies. It was it was not great. But But It happened. And we got that rocket launch. And I think I think the birds were okay, the bunnies were not.

But yeah, coming back to the actual dangers of staging. So as you imagine, as Charlie explained, you have to drop the dead weight. And then after that you light up, you ignite the second motor, right. So on the second stage, you ignite the propellant that's there after you stage. And you don't want to do that just in any condition. Because if your second stage is pointing downwards, you don't want to ignite the engine, because that will turn your your nice rocket project into a very dangerous mess style. And actually, a lot of our legal implications and, and struggles we have come from the fact that our rockets aren't very far from, you know, missiles, in their shape and the way they behave.

What's the what's the defining factor between a rocket and missile? trollee?

There really isn't one. Yeah, yeah. So, so actually, to this day, if you launch from a military controlled launch site, they will say missile away when you launch a rocket. So the the I mean, the ultimate distinction between a rocket and missile is, you know,

attended use probably, yeah, one of

the weapon and one is not, it's either

for science or for murdering bunny rabbits.

But their truck was for both of those. It sounds like

it could be both right? You know, you launch you launch a rocket that's got some missiles on it for like anti satellite or so I don't know. I'm just being

facetious. Yeah, no, it's I think the payload can make a difference. And definitely the way you define it and the way you define successful mission.

I think Luke, Luke actually hit the nail on the head there. The mission, if you write the mission of a rocket is, you know, deployment of some payload for some purpose. And you know, the mission of a missile is to hit something hard and fast. And I think if our rocket hit something hard and fast, we all we all go home crying, right, you know, I gotta build another one. So So I think that's the difference right there.

Yeah, you guys. You guys want your missile back?

Yes. All right. Well, not all not all rockets are recovered. Right. So a lot of launch vehicles, especially the larger they get are not actually recovered. SpaceX and Blue Origin are changing that. But you know, still, most rockets are expendable. Because remember, we were talking about how the the ratio of Fuel to rocket is what defines how far you can go. It doesn't care if you're bringing a parachute with you. That's still wait, you didn't spend on fuel? And that'll that'll hurt you.

So in rocket design, what kind of testing Do you all have to do when you're building and developing this technology?

So we do all sorts of testing. And we, the only discussions we have about testing is are we doing? Are we not doing enough testing? And how can we do more testing? Because, yeah, it's a large project. It's a, it's a lot of you just want

to spot my heart right there.

Yeah, you we put a lot of engineering hours into this. And everything is can be decided in a matter of seconds, like, like it was this July, when we lost Herbies to do to fin failure, seven seconds into flight. So we ignited the motor 7356135 seconds after it's all over, you know, and you definitely don't want to the one that happened, you you hate to see it. So that's why we do a lot of testing. This testing ranges from very basic elementary tests at the smallest level. So in our software, even with the unit tests, which are testing every single component of the code, then we put those together to test the code itself, then we test hardware separately. Now it does code on the hardware. Then we test all of the hardware mechanical components we have. So we assemble a motor and then we have a static fire where we just attach the motor and pointed, pointed upside down so it's right right. So pretty much what we do with that static fire is just characterize the motor. The pretty much just tell that's the motor in isolation and get its curve, its thrust curve with get its pressure curve, and pretty much see how it behaves. Sometimes it also blows up so the static fire is done. With everyone being very far away. And just some cameras and microphones on the site. And yeah, Charlie, if you want to talk about it more, you were many more static fires than me.

Yeah, so about about the rocket motors, so y'all build the rocket motors yourselves, then,

yeah, we make them from scratch, which is so so I didn't say this in my bio, but I, this is my fifth year on the team. So I've been around since the team had about 10 people. This year, the team has 120.

Is that because of Kerbal Space Program? No, no,

it's probably because of recruiting events. So like, you know, so we always used to get, like 110, people would come to our first meeting, but then you know, our rockets weren't that cool, we weren't that good. We, you know, we didn't have that much work for people to do. So people kind of drift away. But now, we've built a much better base, we're able to utilize those resources and support more people making a rocket motors a pretty pretty involved process. So you start by acquiring all the chemical precursors that go into your rocket motor. And then you go through a process called mixing where you take these polymers and you chemically mix them, and then you cast them into the shape of the solid rocket fuel, which is actually a very important step, the shape of the rocket fuel is what controls how much thrust the rocket motor produces. And then you allow this propellant to cure, you assemble several different slugs of propellant, we call them grains together, that way, you don't have to cast it all at once. And you You put them inside of a thermal liner to protect the case from the hot combustion gases. And then you install closures to create a pressure vessel at the nozzle. And then you've got a rocket motor. And this this philosophy holds true between you know, little Estes motors you purchase at the hobby store, all the way up to the the pea size motors we create for our rocket and hopefully in the future Q and R and S sites, motors. So the the processes is really the same, the question is the scale that you operate at. And of course, you know, there's some hazards to this because you're literally mixing rocket fuel. And, you know, that's the chemicals themselves are a little bit toxic, and they're all very flammable. We're working with powdered aluminum, that's explosive, ammonium perchlorate that can actually be a rocket fuel all on its own. If you heat it up too much, it'll decompose exothermically. So a lot of fun stuff.

What causes these sadock rocket fires to fail, then sometimes, it's just because like improper mixing or or a bubble and you're in your resume, and you're poor or something like that.

Yeah, you hit on actually a couple of key points. So there's there's two categories of errors, there's design errors, and there's manufacturing errors. And, to this point, most of our failures have been actually I think all of our failures have been manufacturing errors. So design errors, or like things where the design never would have worked no matter how well you made it. Whereas manufacturing errors or things like an improperly compressed or rig, a scratch on the thermal liner leads to a burn through which leads to the metal melting, leading to the case, melting itself, a nozzle that cracks because you made too sharp at the corner on it. So a stress concentrator causes it to break in half, like you said, a bubble in the propellant will cause a void, this will cause a radical increase in pressure for a brief period of time. If your motor case isn't strong enough, that can be enough to eject the nozzle from the motor. And those that's a that's a failure we've seen before. There's there's a whole list of them. And we've just kind of internally built up knowledge about how all these failures can happen and ways to mitigate and check. So how do

you go about the failure analysis of something that just exploded?

Oh, boy, it's an interesting question, because we've done this before. And you know, when you first walk up to it, what you really see is you see a pile of charred parts. And everyone's first temptation is to start grabbing everything and turning it over and picking it up and looking at it. And you have to you have to, you know, grab anyone who starts to make a break for it and tie him behind you. And first thing you do is you take pictures, pictures of everything, where the debris is landed, how far away it was, you know what condition it was, was it charged on both sides as a charge on only one side. And then and then we began a process called a trash bag recovery, which is as sad as it sounds, you get a trash bag and you very carefully put everything into it. Both indicating on a metaphysical level what it is, it is trash, but also on a spiritual level how you feel. You feel like trash. And then and then you put this trash bag in the car. And then you you drive to a fast food joint that accentuates that feeling of trash this you have, and you eat some cheap trash, junk food. And then you go and then you go home and you pull out the trash bag. You set all the parts on a table and you try and fit them back together and you see what's missing because what's missing is really the first important piece of information you

can discover because that's that what vape Right is first, right?

Well, it tells you where the problem started. It may not be what caused it, but it tells you where the problem started. So like, sometimes that's not helpful. I remember on the very, what was the variance on the third rocket motor, we static fired, we had a Ford closure failure. And more than 14 inches of the case was just melted. It was liquid aluminum on the ground. And he like picked it up. And it looked like if you just like take an aluminum out of a foundry and just like poured it on the ground, that's what it looks like. So there was like no information to be had there. Other than that it was melted. Right. And it clearly it was very energetic failure. So then, then you start looking for other parts, right. And so what was held at the other end of all that melted aluminum was a piece called the foreclosure. And the forward portion was actually found in tact several 100 feet away, which told us that the foreclosure has been ejected forcefully from the rocket motor. But this is a good place to start our failure investigation. And when we found the foreclosure it looks it's a foreclosure is normally a disc it's a circle, and we found it, it looked like it had had a slice of pie cut out of it. And we were actually able to trace the failure back to an unsealed joint where hot gas had leaked through the unsealed joint and eroded away this pie shaped wedge from it, which then liberated this disc throwing it out, and then all the fire was coming out of both ends of the rocket motor. But of course, while the nozzle is rated for all that heat, the other end of the rocket motors just aluminum so it melted. And that's how we were able to deduce what happened in that failure. And of course, you guys, you guys may not realize this, but the exhaust, the primary exhaust compounds are water, carbon dioxide, hydrochloric acid, and Alumina oxide. And of course, Alumina oxide is the primary component of sandpaper. So our rocket exhaust is not just hot combustion products, it's actually like Mach Five sandpaper. So you know, the typical surface.

It's like a water jet, except it's a fire jet fire jet cutter.

That's that's exactly what it is. Yeah, it's it's, it's harder than Garnet. So that's, that's exactly the problem. So any unprotected material in the exhaust stream will be eroded away almost immediately. Which is how that pie shape got generated. So. So this is just one of the like, counterintuitive things that you like, see, we had some other interesting failures, like we had one where we just didn't put enough glue on a joint. And you're like, oh, so like came unglued? No. So we were using the glue as a seal and hot gas leak through where there wasn't enough glue. And as we just talked about the hot glue, the hot gas acts like sandpaper, it just blew through it. And then you know, waterjet, it's a hole through the case. And then once the rocket motor loses pressure, a nifty feature of the rocket fuel use is actually that it can't burn at atmospheric pressure, you have to raise the pressure for it to burn successfully. So if the pressure ever, you know, decreases, it'll actually shut down. And so this leads to this really weird case where you could approach a failed rocket motor and find it still half full of rocket fuel that is stopped burning. And of course, it's gonna be very hazardous, because it can still be very hot. So it could still reignite. So you have to you have to take precautions when approaching a failed rocket motor, but

so the actual the nozzle if it, how is it designed and how is it made? And what's it made of to be able to withstand Mach Five sandpaper?

Great question. Typically, graphite graphite is a good material choice, we add a blade of coating of phenolic, this phenolic undergoes a phase change. And as it changes phase, it absorbs a lot of energy. And it also creates a layer of cooler gas along the wall to help insulate our parts from the hot combustion gases. Some parts of it are aluminum. Some parts of it can be carbon fiber, there's a lot of options. None of them will survive steady state rocket operation. So you're, you're really just selecting materials that you can control the failure or like the destruction of in a controlled fashion. So you're like, alright, well, I know graphite will break off at this rate in the rocket environment. So if we make at least the stick will be okay. Same thing with the phenolic. Same thing with the aluminum.

There are consumables along with the fuel. Yeah, yeah,

exactly. Yeah. Our rocket motors are recovered, but they're they're functionally single use. Like maybe you could use the case again. I'd be worried about that because I think it gets D tempered by all the heat. But But I really wouldn't use any part of the nozzle again.

How do you actually go about shaping the nozzle? Is it put turned on a lathe or?

Yep, I've turned the lens of the thing. So you look like a coal miner for about a week afterwards? Because the graphite covers your face and you just you can see exactly where this your goggles were on your face as you turned it. Usually you have a little vacuum to try and keep the dust down. But uh, but yeah, it's it's an experience.

So after you built and tested your rocket parts and stuff, who do you need to go to to make sure that someone doesn't say it's a missile? And it's actually a rocket. Like, who do you need get permission from to launch this thing?

Look at you and you're gonna

take this one. I believe you you did most of the FAA waivers yourself, Charlie. I did. But I can start explaining I have

a little bit of trauma.

Yeah. So we need to words you hear a lot when planning launch our FAA and waiver. So pretty much we have to fill out this and get an FAA waiver, which is the Federal Aviation Association. Is that it?

Administration, but Yes, finally. Okay. Well,

I was close. So, pretty much we have to you know, a rocket goes to the One, the One Two years ago went to 10 kilometers or 32,000 feet, this one was supposed to go to 280 1000 feet or almost 30 kilometers. A bit more actually. or less. Okay, I'm bad with converting, it doesn't matter. Something around there. And yeah, most commercial airliners fly at 30 to 40,000 feet. So you know, our even though our rockets going up, if there will be an airplane above it, I'm pretty sure it will just pierce right through. And that's not something

that would have turned into a missile at that point.

I can I can hear the FAA watching this mission change already?

Ground to air missile? Yeah. So pretty much yeah, the FAA will, we need to we fill out a waiver in which we describe how how, how high will the rocket go, we have to describe our analysis for like, we have to provide analysis for landing. So we have to say, Okay, we estimate that the rocket will with this kind of inclination, and this kind of winds, it will land approximately here. So into this a lot, a lot of thought has to go into this. Because first of all, we don't launch our rockets straight up, but we give them a slight tilt at the start. So that because if you launch a rocket straight up, the winds, or the its pitch can turn it anywhere. But if you like, if you fire it at a certain direction, you know, it's going to go into that direction. So usually we do that just to you know, get a better idea of where it's going to come down. Because it can happen that the rocket comes down.

This summer, the the ballistic recovery was not recoveries, fault recovery, avionics, and recovery deployed the parachutes. It just so happened that there were no parachutes left to deploy.

To briefly cover though, what that looks like. So you get permission from the FAA, like Lucas said, You got to cut them some slack. But then on the day of launch, you submit a submit a call to the local flight standards district office, and you let them know that you're activating the waiver. They then inform the air crews in the vicinity that there are operations occurring in that area and to steer clear. So technically, it's technically it's the pilots fault if they have a rocket shaped hole in the bottom of their airplane. But we can't rely on that because it doesn't matter if the pilot was dumb and flew over our reserved airspace. Even though we asked the FAA for it because I'm sure the papers will still crucify us just the same. You know, for shooting down an airplane so we really haven't we take care of we we can't fly through clouds we check the airspace. I remember this last summer, we had to launch the rocket within half an hour or not fly that day because the military was doing a predator overflight to survey for earthquake damage at their air force base, or the naval air station nearby. So we get we got a phone call, we're like, Hey, we're shutting down your waiver in this much time because the military is flying a drone so just kind of like these are these are the adventures of rocket launchers.

And if I was the military, I would have practice shooting down your missile or rocket rocket.

So do you have to do you have to pay for this is there like a fee?

There's no fee to file with the FAA. It's it's public airspace. You may have to pay a site fee depending on where you're launching from. I think we pay $10 a launch for our launch site. Which is kind of funny. It's like a whether it's a $30,000 rocket and we pay $10 to launch it. The old site we used to use had about $1,100 A flight in launch fees. It was just a little different. It had more infrastructure. You pick your site and you make it work. There's one place on the east east coast you can actually launch these rockets from Wallops Island, Virginia, we looked at flying out of there. And the two problems were one, we'd have to recover the rocket from the water. So we'd have to, like waterproof everything and put a flotation system on it. And the second problem was that they wanted like $100,000 a watch, cuz they're used to supporting like, actual rockets, like, you know, SpaceX and Orbital ATK are, I guess, so sorry, Northrop Grumman innovation systems. And so they were they were just like, now we're going to charge what we charge that and we're like, we can't pay that. So we spent a year, maybe two years, maybe three years,

so you shouldn't use a.edu email address and gotten that student discount? Are you?

Are you kidding? Me? Hello, this is a student from MIT rocket team. We're poor and broke and trying to launch rockets, will you please give us free things? And then when they say no free things, and we started talking about what we'll pay them? Yeah.

I mean, using a edu email, that's the pretty much the description of what I do on the internet, every single thing. It's just like, you know, gotta use

a good segue to plug a plug the good things macro fab has done for us, right? I wasn't paid to say the three thing. But But macro fab very generously helped us get some of our parts made, which is which is, you know, essential to what we do the in kind sponsorships, you know, not a lot of companies give us money. But the companies that let us get parts made, that's, that's critical. And we make almost the entire rocket from scratch, we lay up raw carbon fiber into aerodynamic parts, we machine the motor case, from stock aluminum, we cast our rocket fuel from industrial chemicals, we you know, build and program or on flight computer, we sell our own parachutes and, and the companies that are willing to give us the materials expertise and Tool Time to get make this happen are really essential for this rocket happening.

I just hope it wasn't a little red PCB that made that rocket blow up.

There wasn't avionics, avionics hasn't crashed the rocket the entire time I've been on the team. We've we've had a couple of recovery failures, we've had a couple of propulsion failures, we've had a couple of structural failures, but it's ever been avionics. So you can take that one to the bank.

So speaking of that, what kind of electronic hardware Do y'all run? So?

Yeah, our rocket has actually, the so the the rocket, how it's structured pretty much is the motor case, the mission package, and then the nose cone with the payload. And the mission package is pretty much the recovery system with parachutes, and then the avionics bay. And the avionics bay is like a hexagonal structure that's just full of boards and electronics and batteries. So what we run is, first of all, we are we have to commercial off the shelf altimeters on there first, because due to time, pressure and developmental efforts, we weren't able to complete our own flight computer reliably. So we're not flying it in command yet. So it's not the one that is responsible for deploying the parachutes. But it is like the hardware is there. The software is almost there. And we are just pretty much a few tests away from Eclipse. So

using a so using a off the shelf computer currently to get through like designing the the propulsion and and structural stuff. And then your your computer that you're designing piggybacks off that for the ride, right, for now.

For now, yeah, but also it does a lot of important things. So the only thing that it doesn't do, which is which is the most important thing, parachute deployment. And then on staging demonstrated also staging, and Second Stage ignition. But it does what it does for now is it monitors and turns on the cameras. It's, it maintains a stable and much better radio connection than the commercial ones do. It's it records data to much more detail and with better sensors than the commercial ones. So pretty much when it was built, it was built with the intention to replace the commercial ones and be better at better at all the jobs that commercial ones are doing right now. And yeah, it's pretty much there just like we ran out, we're on a tight schedule for Hermes three. And we'd rather just go with a little safer option and fly with their computers with the commercial ones. But then we will collect data on our own one and then we'll have this data to test our own computer. So it will be ready for special. But yeah, to continue. So we have two commercial ones. We have our own computer. We have a camera aboard and connect the cameras through their USB connector. It's pretty cumbersome, but that just Right now we're sticking with those cameras, unfortunately. And they're just how we have to do it. And it also collects feedback from cameras, which is what we're working on right now. To see. So on the launch pad, we send commands to our computer, and observe if the cameras are recording or not. Because video is not the most important part in most rockets, because the most important part is the payload. But for us, PR is all we have. So having video from,

say getting that sweet Instagram shot is probably the most most

Exactly, exactly. So video is really important to us. And yeah, we were

we were just talking with the crew from from relativity space. And they said, you know, they said, you know, our primary mission is to fly customers payloads to orbit. And if we miss some video, you know, so be it, you know, as long as we still successfully deployed the payload, and we're like, no, no, no, you got it all backwards. You see, for us, we are getting paid to do this. We're paying to do this. For us. If we don't get any video, did it even happen?

Yeah. There's video recording the rocket taking off, but that's just you know, like, a few Milli, a few milliseconds, a few, a few 100 milliseconds, if you will. But still, that's all you see. And then it just just the, the trace in the sky. So not having video from the rocket is definitely something we don't want. And it's probably one of the biggest things we get from the launch.

So what kind of power do you run? Like go kind of batteries? Double A batteries, nine volt lantern battery?

What what on earth? Is this two cell lipo on the rocket for? I've been trying to get an answer for this for like weeks. I'm sorry. I'm taking this opportunity for some for some technical discussion.

So what are you asking? Why are we using a to s instead of a one? That's lipo?

Yeah. If you if you get this done, well, what is life? Well, we have full battery commonality. And then we don't have to, like worry about which battery goes where?

Well, that's that's a very good point. But I believe that at least one of the sensors I'm tempted to say GPS, but I'm not 100% Sure. Is, is running on five volts and not 3.3. I think in general, oh, you're killing me? I think so. But I'm not 100% Sure. I think I'm pretty sure I'm like microprocessor

slap a boost a boost converter in there.

I'm pretty sure that you can

just run a little boost converter. Yeah, yeah.

There's some, some.

I mean, it's, it's not necessarily worth it. I was I'm an I'm a Systems guy. So I look at this. And I say, while we're maintaining, you know, three parts for the two s lipo when we are already maintaining three parts for the widest lipo if we can kill the one two s life on the vehicle, right, then, you know, all of a sudden, now we have fewer peace parts, we have a more straightforward electronics power system.

Yeah. Yeah, it's actually a good question. So last year, I was more involved with the software. So I'm also getting more familiar with the exact hardware. So that's I'm not 100% Sure why we are running off of a to s. But um, I am sure that it is because one of the components at least requires five volts. And that's why you can just run it off of 313, we have a separate battery for a couple of things. So first of all, we run a battery and a backup main and a backup battery. You know, just for redundancy there. We also have separate batteries for Pyro channels, although they're not connected. So our flight computer is designed to you know, once, at some point, deployed the parachutes. And how we deploy them is with a pyro charge that ignites the actuator that pushes the piston and separates the rocket into parts. And those fires are, are to be controlled and powered through a separate battery. But as I said, our computer's not deployed parachutes. So I don't think there's a battery for pirates right now. And yeah, so I haven't finished with the list of hardware yet. I haven't mentioned cameras yet. And then the other thing we have is DAC, or the data acquisition board. So that's actually payloads, not avionics, but it's still still a board that ends on the rocket, we have a couple actually one in the nose cone, and one in the lower electronics, which is next to the motor just above it. And those DAX pretty much what they do is just collect a lot of data. They collect more acceleration data than our own than our main flight computer, and they can collect thermal data and a couple of other things. But yeah, that's so I think that should be out of the out of the hardware. I was trying to hardware that we have on the rocket, but I could be mistaken

so And we're running out of time here because Charlie has a modern cell phone that only has one port. So you can't charge his phone and do the audio at the same time.

So we're living in the future.

Yeah. Where? Where can people find more about y'all and the MIT rocket team?

Yeah, so the mighty rocket team has a web presence@rocketry.mit.edu We also run Facebook, Twitter and YouTube channel. And I hear rumors and even have an Instagram. And we post content on that. Occasionally when the publicity cheer me feels like it. And yeah, when he's not being lazy, but who will see chairs usually pretty good at his job. And yeah, so we're we're tracking for another launch in January. That's our next our next plan flight for the watcher curve is 300 staging demonstrators second flight.

You don't want to be in the Mojave Desert in the summer again.

Well, the Mojave in the summer, you know, it beats the heck out of New Mexico in the summer. To be honest, that's where we used to fly from that was much worse. I think it was made it up to 121. Summer while we were there, it was just brutal.

Well, we're gonna definitely have to have you all back on after your next launch.

And we'd absolutely love to be back.

All right, and you all want to sign us out? Yeah.

This has been the micro fab engineering podcast. We were your guests, Luca gurvich And Charlie Garcia. And thank you again to our wonderful hosts

Parker Dolman Steven Craig. Thanks so much for coming on the podcast

good luck and Godspeed y'all. Thank you

Thank you. Yes, you are listener for downloading our show if you have a cool idea, project or topic. Let Stephen and I know Tweet us at macro at Longhorn engineer or analog E and G or email us at podcasts at macro rev.com. Also, check out our Slack channel. If you're not subscribed to that podcast, do it now. click that bell hit the subscribe button. Click Play. 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. helps new listeners find us