This is a rocket-powered golf club. Professional golfers have an average swing, speed of 110 miles per hour, but using two f-size motors. She swings at 150 miles per hour every time usually for builds on my channel. I just show you guys the final thing and don't really talk about the process of how we got there and rest assured.

Today we will get to see huge drives: whoa golf balls, shattering glass in super slow-mo, pulverized, watermelons and even a handheld version, but this build. I think is a great chance to pull back the curtain and demonstrate how the engineering design process actually works. I want to highlight six learning opportunities that led us to this final design and to do that, we need to go back in time four months to when i first had the idea and as always, we started with a simple prototype to see if the concept even Had a remote chance of working, but before we fire it up, you'll notice, we have counterweights on the opposite side here, that's so that the center of mass of the spinning part is on top of the axis of rotation. In other words, it balances perfectly.

At the point at which it spins around, if you don't do that for something that spins, it creates a bunch of extra force for your system to deal with. It starts as a small vibration, but then it gets worse and worse as you pick up speed, since we need to hit this tiny ball with the head of this club at really high speeds, if we're not perfectly balanced, the club and the whole platform itself would Just be shaking all over the place and we'd never hit it. Okay back to the test, those stands are shaking more than they should so we knew we would need to balance the spinning part better for the real test, but at least we knew it could go kind of fast and nothing blows up, and so then it was Time for cad, which is always the next step, and then, together with my friends, ken and kayla, we started cutting metal and making stuff things came together. Well, so we epoxied a 3d printed motor mount to the top of the driver and prepped our first real test by taking one of those easy ups and draping some nets on the side for safety, just in case something went catastrophically wrong.

This was our second learning experience. We didn't have enough contact area for epoxying the head to the driver, so it wasn't a strong enough bond. This was tricky because it meant we had to 3d scan the club head, which allowed us to cat up and then 3d print a more contoured mount with more contact area for the epoxy. We also took this chance to double the rocket holsters, because what could possibly go wrong.

So we went to test our new dual rocket setup with two e-motors and everything went perfectly, except for the part where the head snapped off the driver. That was not expected and when we reviewed the slo-mo footage, what we realized was the shaft of the driver is so flexible that it would start to bend and then create really weird thrust vectors for the rockets, which then just bent the shaft even more. This is not what you want to see. Eventually, this exceeded the stress limit of the shaft and the head just came off, so our third learning opportunity was to stiffen up the club shaft.

So we got some aluminum c channel and just dumped a butt ton of epoxy in there, and this worked remarkably well. You can see the difference here and so with that we headed out to a very remote shooting location in beautiful northern california, so we finally arrived and started to set up, but first i had something i wanted to get off my chest. So one of the things i like most about me is that i will i like to reach out to lesser known channels and sort of give them a handout and some exposure on my channel, which is why today, i'm here with destin a smarter every day. And if, by some miracle you don't know, dustin is on the mount rushmore of science.

Youtubers we've been friends for almost exactly six years, and i know this because i took a screenshot of the huge moment for me when he subscribed to my channel when i only had 10 000 subs he's made videos about the physics of cats landing on their feet. Tattoos in super slow-mo or the first video i saw of him about how chickens have an internal open feedback loop, which allows them to head track if you've never seen his stuff, i'm actually jealous, because you have so many hours of high quality viewing in your near Future, so i like golf, i like rockets, do we do this yeah, it's just that that was the intro right whatever, so we all continued to set up and something that was important to me was for this to look as natural as possible at a driving range. So we added some turf to cover the base plate and then dissected a golf bag to cover the sturdy steel column. And then, if you add some clubs, it looks pretty awesome, it's incredibly rigid and yet it can still swing freely.

Our fourth learning experience came from reviewing our final test footage. If you listen, the club goes faster and faster with each rotation. Naturally, we want the club to contact the ball when it's going the fastest, which in our case is 10 rotations in one second, that means we somehow need to sneak the ball into the path of the driver in less than a tenth of a second or a Quarter of an eye blink to accomplish this, we have a pneumatic cylinder here that hinges up the tee. It knows when to fire, because on the back of the shaft there's a light sensor and this disc has a slit which allows the light to pass through once per rotation.

So we send that info to an arduino over here that counts for us and then after 15 rotations. It tells the cylinder the precise moment to fire using a solenoid. And then we super glue the ball to the tee because it provides the goldilocks amount of force to first secure and then release the ball plus. The super glue looks super dope in slow-mo.

So now, with everything in place, we started with two e-motors, which is a reminder, is the same setup that ripped the club head off three two one roll. What happened? No way, that's a cool shot right there, dude dude! This is uh. This is respectable like this. Is legit after reviewing more of the high-speed footage, we noticed something interesting.

The sound effect there is like doing. This was an interesting technical observation from destin and that t flexibility was causing us to hit some bad shots like this. An obvious fix is just to make the t more rigid so that it doesn't over rotate when it pops up, but there's a problem with this there's a saying that force follows stiffness and for us, a really stiff tee would transfer a bunch of force and destroy Our nice 3d printed pop-up mechanism now imagine this crumpled up piece of paper is the tea, which is obviously way less stiff. Our flexible rubber tee was great because it acted like this piece of paper, no matter how hard you hit it.

The force doesn't get translated down and damage our hardware, so ken had the brilliant idea of just tying a string to the t and staking it into the ground. This stopped the over rotation, but everything was still just as flexible when the string pulls tight. Does it make the ball fly off because it's it doesn't doing enough? Uh only way to test is a doing test. Ah beautiful there was some drinkage.

I just thought this was a really simple, clever idea that solved both problems at once and as you can see, it worked perfectly now we're ready to try a dual f motor, so these deliver about twice as much force to the club as the e-motors that made The head snap off and this provided our final and certainly most poignant, learning opportunity. One go where's: the club where's, the club. Yes, my god, it's the tree on fire wow like i'm laughing, but that could have been bad there we go. This thing was like sub-orbital dude, so we have three u-bolts and we only use two yeah, so i think we'll just max out those and just crank them way down now that we know this is a failure point now that we know this is a failure.

Point there's several failure points and i hear you say: oh, we have a solution for that engineering design process. It's rather fun. Like i mentioned the club that failed was cut too short and therefore only attached using two u-bolts, which we thought would have been enough to support the 800-pound load from centrifugal force. We did notice the rubber handle was worn due to so many test fires which probably initiated the stress concentration leading to the failure.

So our fix was to cut the next club longer. So we could use three u-bolts and really crank them down on a fresh rubber handle, and so with all six of our learnings now in place, we tried the insane double f motors, one more time, go wow! That's how you play golf. That's our best one! Yet dude like the brush you get from like an engineering achievement. Actually working is like seriously dude.

Oh look at the place, so we never found these long balls to measure the exact distance, but i can drive a ball 280 yards and these were well beyond that. I mean just look at this trajectory straight to outer space. Now that we got all the shots we needed. It was time to have some real fun.

We started with a handheld version that was powered by a single c motor because anything more than that would just be way too unsafe for me to hold nice. I, like 300 yards man. It really did like make it so much easier to swing. I'm not even kidding yeah yeah yeah like it really made a difference, three two and then some glass just because and then keeping with the tradition of my channel some watermelon.

So thanks for cutting open a watermelon with a rocket-powered golf club mark you're welcome yeah. That's all of this. The past three months of working engineering was just boils down to this moment just to enjoy this watermelon yeah mark's like trying to make stuff look good, we're not wasting food, though we waste, no part of the engineering effort like the great indians with the buffalo, so Dustin made a video on his channel about why some balls, bounce high and others don't, and my first thought was well, that's easy. Just has to do with how compressible or rubbery it is.

Yet this billiard ball is pretty much completely solid and this bouncy ball is pretty rubbery and yet they bounce to pretty much the same height. So it's something else as you can imagine. This is a pretty important piece of information for golf ball makers. So there's lots of amazing slow-mo footage of golf balls being squished in ways that hurt your brain plus way more footage from today's shoot.

So i will leave a link in the video description and, while you're there make sure to check out some of his other videos and subscribe to his channel because he's just a classy individual and a true professional in every sense of the word. Are you rolling yeah? Hey, it's me mark you.