"The Power In These Flywheels Scares The Pants Off Me" | Savage Builds

[Music] this is adam steltzner a brilliant engineer and one of my favorite people on the planet hey man good to see you i'm good thank you so much for coming on down to help with this yeah you know i had a little extra time to break away from mars oh yeah and he also happens to be the lead engineer on nasa's next mission to mars my day job i work for a place called the jet propulsion laboratory in pasadena california we build spacecraft to orbit the earth and to go out into the planets you ready yeah i want to see this thing right so it's friction with the ground that's making the wheel move forward and the rocket is providing a torque to the device when i saw the panjandrum for the first time i told adam i am in adam is the best kind of engineer he's not just an out of the box thinker he's an outside the building the box happens to be in kind of thinker three two one adam was the mission commander for the curiosity rover landing on mars nuclear powered 2 000 pounds size of a car it was the biggest rover that ever been put on mars or anywhere and to do that we needed to invent a new way of landing we came up with the sky crane maneuver which involved the rover having the propulsion system like a jet backpack and then about 100 feet above the surface of mars the jet pack lowered the rover and the two descended until the surface of mars took up the weight of the rover [Applause] like adam i think the panjandrum is a good concept oh yeah there's a reason yes but it immediately opened up at least in my mind several opportunities for improvement rockets never fire the exact way you want them to fire they fire a little bit much a little bit less and so the thing's gonna be moved around by the rockets going on and off it's not stabilized as much as it could be so i think we've got a trick that we're gonna try eliminate the rockets first and foremost we're gonna try and do this with all the angular momentum in a flywheel wow you can store a huge amount of energy that way it's also fantastically dangerous just like rockets instead of using rockets we're going to use centrifugal force to power our panjandrum so we're going to use the same wheels as the original we're going to move them closer together their axle is going to be a truck axle onto either side of which will be bolted instead of tires big steel flywheels a flywheel is basically a large rotating disc that resists changes in its rotational speed in other words once you spin it up it doesn't want to slow down tapping into that flywheel's energy by grabbing onto it with a break we'll transfer that rotational energy from our flywheel to our inner wheels propelling our panjandrum forward yeah and then we will size these flywheels such that this equation is satisfied and we'll make sure that we spin this bad boy up to the necessary speeds if adam stelzner's equations are correct our flywheels will have to be spun up to a thousand rpm to launch and propel the panjandrum forward at an initial speed of 40 miles an hour tomorrow's mission is to gather our parts and start building our neopanchandra the flywheel's here check technology macaroni seeing those flywheels for the first time it's a little terrifying that is big that's our power this thing is big it's one thing where it's numbers on a whiteboard or a piece of paper it's another thing to see it in the flesh good yes there we go yeah [Music] we've mounted our twin five foot flywheels on a perfectly balanced custom axle each flywheel weighs 450 pounds so it's going to take a fair amount of horsepower to get them up to speed to do that we've assembled a 40 horsepower 72 volt motor and battery package oh wow that's uh close to 7000 rpm the man running our motor is marcos ramirez artist fabricator and electric vehicle mechanic he's going to spin our flywheel up to a thousand rpm at which time i'll uncouple the motor to allow them to spin freely then we'll see if our flywheels and axle hold together under these tremendous forces this spin test we're about to do is pretty much the most dangerous thing we're doing in this whole episode we are spinning this up as fast as we can hopefully past a thousand rpm or about 17 revolutions per second that's nearly a thousand pounds of angry steel rotating at a stupidly high rate of speed if this thing escaped it's going right through that door right through the fence right into the street that's why we parked some very heavy vehicles on the other side of the store one two three up hopefully it hangs together and doesn't rip itself apart the various other failure modes are sounds that are horrifying like you know something like that that kind of vibration could cause our entire pandemic to jump off of its launch platform at the first sign of trouble i will cut this test short and i'm ready to throttle when you are gentle ease it up about one rps now one one thousand two one thousand three or somewhere around here so let's keep on going yes [Music] i'm hearing a little hearing a little bearing yeah now i'm feeling vibration in this i think it's time to pull the plug [Music] everybody clear this side of the building she goes the whole thing shifted because i think as we pulled it off we put applied a torque to it you can see the vibration of the axle can you see the vibration of the axle yep jumping on motion so so that may be the coupler that may be the coupler yeah this is still dangerous don't get comfortable the power in these flywheels scares the pants off me we only reached about 350 rpm roughly a third of our target speed this could have been a runaway train remember how i said once you spin it up it doesn't want to stop watch i'm pushing against this with all my might you could see how much effort it took to slow that down that gives you a sense of the power [Music] there are a lot of potential problems that have come to light because of this test which is the whole reason to do a test uh one of them is that we started to see vibration at about a third of the speed we were hoping to get which means we might have to deal with a lower top speed all right for the people here for this area too dangerous to take this machine past where we did tonight here so we're going to be deciding out at the site how fast is just fast enough

Channel: Discovery Australia

Views: 2,653,308

Rating: 4.7728572 out of 5

Keywords: discovery australia, discovery aus, australian videos, australian youtube videos, discovery australia youtube, adam savage, savage build, savage builds, adam savage builds, ada savage mythbusters, mythbusters, Panjandrum, adam savage panjandrum, ww2 weapon, ww2 experimental weapon

Id: XffkqfymSXc

Length: 7min 55sec (475 seconds)

Published: Fri Mar 12 2021

Reddit Comments

[u/Mathwards]

Here it is "working"

https://www.youtube.com/watch?v=jeoLusNB7P4