Can you create a sonic boom WITHOUT moving??

We're back in Trailmakers making a supersonic vehicle that doesn't move. Can I go 1000mph whilst travelling at 0mph? It's basically a centrifuge for training astronauts but overengineered to the max!!!
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#realcivilengineer #engineering #trailmakers

[@PlaneShaper2]

The aerodynamic blocks pointing backwards also works in real life! Reducing the turbulence of air coming off the back of a solid, and reducing the pressure differential between the front of the solid and the back, will reduce drag :)

[@etaiger]

are you sure? I thought gold balls have holes to increase turbulence and that somehow makes them faster, did I remember it wrong? also, I believe that F1 cars up to 2021 intentionally created turbulence for the same reason, though it might have just been to increase downforce

[@gothfalcon]

@@etaiger Golf balls create a pocket of air around themselves because air has less drag than the material of the ball. F1 cars focus on downforce using as little air resistance as possible. They also don't care if the air for other cars is clean or turbulent where with a centrifuge, you are going into your own turbulence

[@jaronyuriyh7931]

@@etaiger it is true. diffuser on cars basically does the same thing, smoothing out the air behind. aircrafts do add tiny blocks on wings to create tiny turbulence, but those are actually also helping to reduce overall turbulence aft of wings by forcing the air to flow closer to the wing. golf balls work the same by creating small turbulences to reduce overall drag aft of the ball

[@BlakeAStoffel]

Exactly what I came here to say

[@jaggedpancake5353]

@@etaiger f1 cars use a special kind of turbulence called a vortex to assist airflow control in the cars. It’s quite complicated since it has to do with boundary layers, pressures. Basically it helps them cheat the physics of fluid a bit

[@kristianstaalby8499]

Im pretty sure the servo has a rotation speed limit, which is why you had to extend the arms to increase the speed. in some games ive stacked several servos/rotors on top of each other to alleviate this

[@samkimble5610]

Trailmakers doesnt have that as long as you turn down the strength of the servo to 0

[@the_charliecp8859]

Tbf making the radius bigger and maintaining RPM would increase the horizontal speed

[@rccookie6202]

May also be a rotation speed limit by the physics engine

[@chrisakaschulbus4903]

@@the_charliecp8859 It's basically a dirty website with specific fish categories. So don't worry too much about it.

[@ke8wlw]

@@chrisakaschulbus4903 am I missing something?

[@yaksterplayz8434]

Hey RCE you can use anchor points insead of making your base bigger. Better function and less complexity used

[@RealCivilEngineerGaming]

Wut....

[@christopherbaker-stevens537]

Very true

[@blueflash1812]

@@RealCivilEngineerGaming they are spiky blocks and they stick in the ground

[@florianschwarz5541]

@@RealCivilEngineerGaming there is an anchor block, just put on on the bottom

[@yaksterplayz8434]

@@RealCivilEngineerGaming theres a block in the game called an anchor point that keeps all the blocks above it anchored to the floor

[@Ekipsogel]

Two things: one, there is an anchor block that permanently attaches to the first thing it touches, you could grab the ground and stay fixed in place. Two, there is a strength setting in the servos, setting it to 0 makes it act like a free swivel, which should increase the speed.

[@Wasbever_14]

Yes the anchor blocks will probably help

[@kreuinos6333]

@@Wasbever_14 it angered me that he didn’t use them

[@69uremum]

@@kreuinos6333 I dont understand how he can call himself a engineer of any kind in real life.

[@baystated]

Matt's selective memory about physics. Maybe it was his earliest morning course, back in the day. I wonder if the pivot point has a RPM limit.

[@marcusdionne]

the booms were the same length but the weights on each end weren't equal. You get the very slight wobble this way, and maybe balancing the mass might get you the 999!

[@lordgenerias]

So adding a couple of blocks might have solved that one. Question, would making the ends form The Strongest Shape make much of a difference?

[@zyeborm]

@@lordgenerias probably. All the energy going into moving the base around is coming out of the speed

[@johiahdoesstuff1614]

Think the thing that bugged me the most about this was him forgetting to balance the weight of the two arms for the least wasted thrust and a more stable base.

[@ricardozarate2516]

I’m so sad he didn’t figure it out

[@CybershamanX]

THANK YOU. I kept internally screaming BALANCE THE DAMN THING, DUDE! 😜

[@unitrader403]

Thats what an Architect would do!!!

[@AM-hf9kk]

Argh yes! Seeing the base constantly scooting around was driving me nuts.

[@Streaky100001]

Hey Matt, interesting, the "Common sense" theory of those aerodynamic wedges on the back of the arm shouldn't help at all is actually wrong. Real world aerodynamics says that an aerodynamic shape at the rear does help. The reason for this is that as you move through the air, you leading edge (the front of your vehicle) is pushing the air out of the way, in the case of the arm you have with the aerodynamic wedge at the front, your pushing air over the top and under the bottom of the arm. This is great at the front but leaves you a problem behind the arm. You know have a "dead" area that is occluded by the arm, so you have a low pressure zone right behind it, and this has a tendency to cause turbulent airflow and drag and such. Ideally you want to encourage the air to flow over the top and bottom of the arm, and then encourage the two flows to meet up again right at the rear of the arm to minimise that low pressure region. At subsonic speed at least the most aerodynamic shape is a tear drop, with the thicker end forward.

[@Streaky100001]

Also, interesting the sonic boom is kinda wrong in this. You were cheated. You only got the one boom each time you passed the barrier.... you shoulda been getting one everytime the arm passed the camera above the barrier...

[@quinnobi42]

interestingly, at supersonic speeds the wedge shape becomes much more aerodynamic.

[@Streaky100001]

@@quinnobi42 Yep, nice smooth curves for low sub sonic, and nice sharp angles for supersonic. (And don't even talk to me about transonic, nobody knows)

[@bluewhalestudioblenderanim1132]

in real world aerodynamics do change significantly from subsonic to supersonic and altho trailmakers probably doesn't account for this change in behavior . . it is going to change the deceleration by a lot . . . so building a differend design that works above the speed of sound will still be the top priority

[@bluewhalestudioblenderanim1132]

@@quinnobi42 yeah it does . . the higher the speed above speed of sound . the better wedges preform the fastest plane ever made had 2 large wedge shaped tailfins for this exact reason

[@justawarper8397]

Ok so a lot of things you could easily do to make it better, 1: like that other person said, add more spinning servos, 2: decrease the servo strength if you haven't already, 3: use those anchor hook blocks instead of a massive base, and 4, (Unrelated) You should do more trailmakers!

[@Donnerwamp]

The game does aerodynamics pretty accurate, so you also get a bonus from the aero parts on the rear. It's pretty amazing what the devs put in and how good it all works.

[@professorfrog7181]

Pretty accurate up until they modelled the sonic boom as happening once when passing the sound barrier...

[@nyscersul42]

The key to being stable is equal weight on each arm. Sometimes, to make things faster you need to add more weight, like wheel hub weights to balance high speed wheels it just needed a second cockpit and identical arms, or, balanced moments of inertia for the two arms, via a counterbalance weight of the calculated required mass. But, two identical arms is easier hehe

[@teurlinator]

Yes, we need to see the arms identical and hit speeds over 1000mph!

[@shaymin7240]

No, its better to use anchor blocks since if one arm is longer it will go faster. Ancher blocks will make it stuck to the ground making it a whole lot more stable

[@bradgrant1899]

@@shaymin7240 one arm being longer doesn't necessarily mean faster, it's about balancing the forces. Torque being applied at one end needs to be the same on the other end, the weight also needs to be the same to stop the shaking. Easiest thing to do would be to add weight slowly to the non cockpit end until the forces completely balance, that's when the top speed for a configuration will happen.

[@nyscersul42]

@@shaymin7240 You misunderstand... There is no reason why you can't do both. The anchor blocks will stick you down, and that definitely helps, but even weighted arms and basically a spinning assembly which spins evenly and balanced will stop it from trying to shake at all. Like a spinning bike wheel... instead of a swinging pendulum.

[@nyscersul42]

@@bradgrant1899 Tru dat. ;)

[@JanTonovski]

10:21 in real life slopes on the back do help very much with aerodynamics

[@Jack-xh4pv]

Just wait until he finds out there are parts to lock things to the ground

[@Sra33thousand]

That was bothering me the whole video. So much lost energy!

[@forestana2908]

In this game both aerodynamics count (in front of the vehicle and in the back) also the arrows are only shown in the direction of the big blue arrow in the building screen. Finally, you can put a counterweight for the cockpit

[@hypeflexington7081]

When you say both foward and backwards aero count, is the game just counting aero surfaces? Or does it matter the directionality? Like if i put 2 4x1 blocks in a line facing forward, would it calculate the same way ifi only put one forward and one backwards back to back.

[@TankHunter678]

@@hypeflexington7081 The building mode only shows aerodynamics in the direction of forward motion, but the game engine also calculates aerodynamics as if you are moving in reverse as well. So every direction of motion counts.

[@forestana2908]

TankHunter678 is right. Also, no putting two 4x1 in line won’t make a difference. However, putting them facing away from each other will make the vehicle go slightly faster. So if you were to make a vehicle, it would go faster if you make it aerodynamic both in front and in the back.

[@colbygillette]

In trailmakers theres a part called the anchor and it anchors creations to the ground, that would have been useful for this creation where you needed to anchor the base to the ground

[@ChengTeoh]

This feels like the beginnings of what SpinLaunch is trying to do.

[@HDTomo]

Atleast one isn't a crazy sci-fi impossibly expensive and high maintance scam lol

[@LutraLovegood]

Let me guess, hypersonic catapult?

[@LegoDork]

If you balance out the cockpit by putting equal weight at the tip of the other arm it should help keep your base from walking around. That alone coud've got you over 1000 MPH.

[@RegebroRepairs]

BALANCE IT! One cockpit on each arm.

[@mantasr]

Someone uses centrifuges.

[@RegebroRepairs]

@@mantasr I had one in my laundry room in the 90s. 🙂

[@LockwoodMakuRocsBones]

Gee Matt, for an engineer, you sure forgot what a Center Of Gravity was for a good long while there. Much love and still love the content!

[@backyardastronomer]

Lets go!!!! Trailmakers is so awesome!!!! Its a very weird thing though.

[@chaineryt9211]

You are amazing! You always upload great videos! Keep it up! 😎

[@kaichang7858]

would recommend a game called Mindustry, it is a little known strategy game about defending your core from hoards of enemy robots!

[@parz1val205]

To prevent the little oscillation in the base you need to add the cockpit's weight to the other side of the arm to balance out the weight.

[@sindrih]

I do appreciate your iterative design approach to acheive a pre-defined goal. This video should be shown to 1st year engineering students to demonstrate the iterative design process.

[@randallreigns]

You could balance the cockpit arm with a shorter, more massive counterweight to cut down on even more aero. A balanced arm would keep you from losing energy oscillating the base.

[@1_GigaWaffle]

I wish there was some sort of "special effect" when braking sound barrier, that you could feel from inside of the plane.

[@kadboodle]

I was starting to think about if you had made it with 4 arms, 1 in each cardinal direction, you could probably get more speed, then I realized what that’d look like with engine stacks 😬

[@johnnybebad2384]

Bet you did nazi that coming

[@countfrackula6707]

Wouldn't an X shape work better for more thrust? Also, you should figure out how much 'weight' the cockpit has and balance that out with extra weight on the other side.

[@alansmithee419]

The reverse slopes also increasing speed does have a potential real-life explanation I think (though I doubt it's why it works in-game). Essentially, having slopes in the back prevents large vacuums from forming behind the arm as it moves. These vacuums would pull the arm back, slowing it down (or rather they cause the air in front of the arm to push it back into the vacuums - of course vacuums don't suck anything).

[@BarryTGash]

"You can see his eye and an eyebrow - he's fine!" Literally, that was all that was left - an eyeball and some hair... :D

[@zacharywiedrick6224]

Go RCE! I love trailmakers keep going with your amazing content!

[@beaniiman]

looked like the base wobble was taking a lot of energy out of the system, probably make the base heavier so it moves less?

[@TheZeZeToP]

At 10:43 it seamed as if things were going great…but then catastrophic failure. Cracked me up

[@AsloAso]

Turbulence does occur on the backside where it flat. Trucks and their box trailer are a great examples of said rear turbulence.

[@plasmaproto]

One big thing, when building something that rotates, you want to have the same rotating mass on either end, so if you just added another cockpit to mirror the build it would be stable and it would spin faster

[@dinoeebastian]

I was literally just talking with my brother about you playing this and making sonic booms without moving yesterday xD

[@ApotheosisTK117]

The fact that he never thought to fix the imbalance by simply adding a second cockpit to the other end is truly astounding lmao

[@antekmebee]

I love when you play trailmakers! :)

[@precumming]

You don't necessarily want to put the force on the end. There's a tradeoff with more torque on the ends vs higher speed in the middle. You can trade torque you don't need for speed by moving it inwards. It could be possible to use a get engine to move a pivot such that the end goes faster than the exit velocity of the jet

[@ducati_red9162]

My thought exactly

[@pulli23]

Actually regarding aerodynamics: the major force if you are below mach 1 is pressure drag, mostly due to flow separation. Which is fancy for saying that the object creates a vacuum behind it. To combat this a shape like you made at minute 5:50 is actually good, better than on the fron side. You can easily see this with aircraft wing shapes.

[@ronnydarko9046]

We need a pt 2 with some of the suggestions from the comments in action.

[@jaredbredenhof9185]

I love how you used the scientific method and changed one variable at a time rather than just going crazy Great video!

[@FireheartIndustries]

Use anchor blocks (they look like spikey bits) to fix the base to the ground to eliminate wobble. That slows you down. Cockpit on long arm, and counterweight on short arm. Use weight blocks to offset the mass. Balance it as best you can for best results Aerodynamics are actually modeled semi-properly in this game. Wedges facing one direction only WILL produce downforce, and having a trailing edge does actually improve performance.

[@nacoran]

I'd think you'd want some rockets on the end (the most torque) but also some closer to the middle, since they'd be pushing on a shorter lever. They might not have the torque to get you up to speed, but they should translate into higher top speed since they are traveling a shorter distance each rotation. The real question though would be how fast is the thrust from your rockets. It might not be necessary. You should see if you can get the developer to add an anchor so you can anchor to the ground. It would be cool for making slingshots and such. There is actually a company trying to launch satellites using this. They've built a partial vacuum to lower air resistance and a super fast door so they can release it. By doing an airlock they can preserve some of the vacuum. They are hoping to be able to do multiple launches a day when the technology is mature. It turns out that most satellites are already hardened (and designed to be super light, so the G's aren't that bad on them).

[@user-ct2yf5bd4h]

downslope at the back makes aerodynamics better too (both irl and in the game)

[@shveylien7401]

The no drag link connectors are the way to go, and putting the engines at the best speed position but extending the links for the cockpit would be better. Also counterbalance the cockpits weight with something heavy but close to center, think trebuchet. Make it 4 bladed for more motors at peak efficiency radius.

[@michaelcherokee8906]

Really good ideas

[@dragonbutt]

*Looks at title* *Thinks about constant speed units on props that go out whilst on the ground* Yes, yes you can.

[@joshbissinger7422]

This was fun! You could try putting weights on the base for stability.

[@tizwah]

6:15 the triangles on the downwind side actually do make a difference - they reduce turbulence, and hence drag, so the simulation is actually correct!

[@Templarfreak]

5:57 as far as my understanding of aerodynamics goes, this does have some impact. i dont know exactly how much, though. but for one example of where this definitely matters, think of like, ailerons on a plane. iirc they make a plane turn by creating an imbalance in pressure between the top and bottom of the wings.

[@pipecleanermaster]

Man I remember when you were only a bit above 200,000 but now you’re already well above 1 million congratulations!

[@AgentWest]

This is basically a tip-jet helicopter. Though it was interesting to see the game recognize the speed as a sonic boom while the whole creation was technically stationary, i don't think it used to do that.

[@Thetealeaf1984]

So like, wouldn't this liquify the person in the cockpit? I mean, that's a lot of centripetal force.

[@MNbenMN]

TIL, if they still have an eye and an eyebrow, then they are not jelly

[@cameronsmith1131]

I knew the answer before even watching the video, ive experienced sonic booms everytime my dog is asleep on the couch after getting in to something he shouldn't

[@anonymous-mj8wb]

I almost had a heart attack at 16:57 when someone whistled. I’m home alone with earbuds on at 4am. I thought someone broke into my house and started whistling

[@herculesplays2378]

I love your vids keep it up!

[@scottishpope]

I would like to see you and @ScrapMan in an evolution build-off. This is his jam!

[@Nilguiri]

Try balancing it. Make one arm slightly longer/shorter until the base doesn't wobble. Or better yet, put a cockpit on both arms so that each side is identical.

[@meegstomtom]

I was thinking the same thing. The weight ist symmetrical causing wobble.

[@kaydenthat8222]

The main reason stacking the engines increases the speed that much is mainly due to the extra moments it gives because moments = force x distance^2 so.... pretty self-explanatory

[@trevorbiltmore2422]

Man he’s a real good architect

[@jjlane9191]

I really wish I had a way to record both my game and my voice that way I could explain how aerodynamics work in trail makers. Mostly because watching this was pain.

[@GamerDudeBYT]

To make the device stop shaking RCE should put an anchor on the bottom and anchor it to the ground.

[@prof.tahseen6104]

You could stack the engines vertically and use anchor points. Also I'm pretty sure that the servo motor has an RPM limit.

[@felipew101]

The trailing edge aero also has an effect. Not as large as the "front facing" aero, but still.

[@mfk12340]

The aerodynamics of the back are important in real life. In looking at subsonic speeds we simply need to drop a fluid and it falling through the atmosphere will create a decent aerodynamic profile. Which is a raindrop. Which if you look at plane wings they match this theory. But I haven't studied this for awhile so I may be misrememberimg.

[@ThatUnrealGamer]

*The ball joint just doing its thing* RCE: "Well the ball joint isn't working very good"

[@jonfox17]

I believe that the reason why shorter arms with more rockets did not work is because the game locks the gear at a certain rpm. So by figuring out the distance away you need to be from the center to get a tangential speed of 1000 would have been best thing to do.

[@Unorthodox_kidd]

I mean uncommon sense tells you that added the slanted pieces to the back gets rid of that low pressure zone and in turn improves aero. Lot as much as it would on the front but its still an improvement

[@ColinTimmins]

I really loved this video in how you systematically tested the game engine to see how it worked and what was best to use for your shenanigans! It truly gave me the strongest shape possible!

[@garagebandguy2793]

Hello there love ur vids RCE!

[@chasechristensen9539]

Has anyone thought to tell him about counter rotation? He's basically made a helicopter's propeller, and the way they stop the helicopter itself from spinning is adding either a small propeller on the tail of the craft, or sometimes add a second propeller under or parallel to the primary propeller to counteract the rotation.

[@xtrim1993]

literally EPIC gameplay :D these speedbreaking vids are always funny to watch hahaha

[@alansmithee419]

4:00 *torque, not moment. Moment, or moment of inertia, is a measure of how much of an affect torque has on the spinning of the system (not how much torque there is on the system). It's increased by adding mass at a distance from the centre (making the arm longer), while torque is increased by adding a force at a distance from the centre (placing the booster at the end of that longer arm). rotational acceleration = moment/torque Just as linear acceleration = mass/force, they are analogues for rotating systems.

[@foxboi9032]

You can also put the seat closer to the center because the center has a faster rotation than the outside, however the engines towards the outside makes it faster

[@sparking023]

oh look, by the sheer power of physics Matt inadvertetly joined the Wedge Gang. This design was not only efficient, it was *professional*

[@rbencez]

RCE, try balancing the weight for stability and put down slopes on back of the arms, because that reduce drag too!

[@adamneff4512]

Really enjoyed this episode

[@troypequin2202]

levers work by inputting force from the centre, you could go much faster although with slower acceleration by placing the jets in the middle of the arms

[@Real_Claudy_Focan]

Whip "snap" noise is a sonic bang. No need to go fast or far or complicated Playing with angular velocity is fun.

[@icarob-eng]

If I was a physics teacher I definitely would use this in my class

[@GWPRO_YT]

Very fun and Good video Love your videos

[@revampedharpy09]

4:20 higher moment for the force, and higher speed for the same RPM, but also higher rotational inertia, bit of a double edged sword

[@alansmithee419]

"We did it, we broke the sound barrier!" *Looks at readout* "average velocity 0m/s" "Wait, what?"

[@adamiroronra]

Next step, add 2 rotating arms at the end of both rotating arms (with engines of course) and check the speed of the cockpit with a double rotation :P

[@emperorphantom8242]

Most of the aerodynamics and length problems I think could have just been solved with counter weight with a shorter arm if you think the magnus affects ways in here that’s why the stability is off because the top wants to move wherever the rockets go so in some cases more rockets less speed not to mention like a ballerina or ice skater when they move there arms closer to your centre of gravity you will have less resistance and drag ergo more speed

[@RealAndySkibba]

Centrifuge arm is really cool.

[@leax_Flame]

That was a very interesting video.

[@someonenoone4213]

you could use the spikes for the bottom + an extra roof support reaching down for max stability

[@jonfox17]

At the start I just could not stop thinking that an architect would have probably had a better start.

[@icarob-eng]

I think that on the topic of aerodynamics, the more mass the better, cause you would have more inertia to pierce through the air. It just make the machine achieve terminal velocity more slowly, but theoretically, a bigger velocity.

[@ph0end]

Great video, distracted me enough that I almost forgot to ask how an engineer can call this 'not moving'

[@zurknjurk]

with this title question in mind... as an electrical engineer i'm curious at what speed high frequency signals are transmitted through the atmosphere. pretty sure the particles move faster than sound, but dont emit much sound? i guess because of the minimal mass.

[@Rose_Butterfly98]

In real life, putting those wedges on the back would still reduce drag. And trailmakers apparently simulates that even if it doesn't show it.

[@Random_Meme_Maker]

I was waiting for you to play this game again

[@Nhs2Buzz]

Nice lawnmower RCE

[@mrpotato128]

You may have not been able to reach 1000 mph before when you made the arms longer with more engines because the platform was shaking like crazy up and down not side to side. Because if you look at the platform then it was "jumping" that's why you need to add more weight onto the platform. (you could have also added aerodynamic blocks onto the base so it would make it faster)

[@ltcolthorin8661]

There's an anchor point piece that will make your machine stick to the ground. That way you don't lose all that energy moving the base about.

[@Acs2004]

Either my calculation is off, or that guy is experiencing 840 g. So the cockpit appeared about 14 meters from the centre so that's "R", mass is assumed to be 50 kg and velocity is 340m/s. By mv^2/R, that is 412000 newtons of force, By F=ma, his acceleration is 8240 m/s^2. Or 840 g

[@mackobun]

Try using the spiky anchor blocks to hold the chassis to the ground while the arms rotate. You're losing speed due to chassis counter rotation

[@fiercemidget]

The G forces on this guy

[@blazergangfan6220]

Hey, just wondering if you are planning to continue the trailmakers space game thingy?. I recently discovered it in the goldmine that is you channel, but the happiness was short lived after I burned through all of the episodes in no time. Sincerely: Me.