Typically in the RC community, radio control boats rely on small nitro engines or electric motors to get around. Fitted with traditional propellers, they’re capable of great speed and performance. Of course, there’s more than one way to skin a cat, as [Integza] shows with his latest build.
As far as the boat side of things is concerned, it’s a basic 3D printed single hull design. The innovation comes in the drivetrain, instead. The boat uses compressed air for propulsion, stored in a battery of four soda bottles, pressurized to 6 bar. The compressed air is used to drive a Tesla turbine of [Integza]’s design, which is 3D printed on a resin printer. Rather then driving a propeller, the Tesla turbine instead turns a Lily impeller, which pulls the boat through the water rather than pushing it along. The impeller uses a nature-inspired design, hence the name, and was also 3D printed, making producing its complex geometry a cinch. The guts of a toy radio control car are then used to control the boat.
Understandably, performance is less than stellar. The limited reserves of compressed air can’t propel the boat long, and the combination of the high RPM Tesla turbine and Lily impeller don’t provide a lot of thrust. However, the boat does move under its own power, demonstrating these oddball technologies while doing so.
[Integza] has been working with these technologies for a while; we featured an earlier Tesla turbine build back in 2018. Video after the break.
It’s fun if you’re in the mood for fun, which, clearly, you are not.
But presenter performance aside, the result was somewhat underwhelming. Would have liked a little more investigation into why. The impeller doesn’t seem well suited for pushing the water back; probably pushing more outward than back.
I wonder if the impeller would work better if it was placed inside a pipe or tube of some sort, to contain the water and allow it to push out.
Yes absolutely it would. That contains all the water and sends it into the correct direction as thrust. Notice a jet ski impeller is not hanging out in the open – it’s in a tube that is a pretty close fit to the outside of the impeller.
All ‘aerofoils’ (propellers, wings, etc.) do that to some degree. An awful lot of time and effort (and money) has gone into research aimed and reducing and/or controlling edge effects.
The original Tesla turbines performance relies on the turbine disks being very close to each other which takes advantage of surface area adhesion. If the disk spacing is not closely controlled, high bypass is inevitable. Balancing will also affect ultimate turbine speed. Dry ice and water in the bottles would have been a better motive force. Pressure using this method in a 2 liter pop bottle will exceed what can be pumped in the bottles with a pump. Interesting project none the less.
Dry ice in the bottles is a kickass idea… potentially explosive, but still awesome. I’d find a digital pressure gauge and arduino to monitor it and have it self-release pressure when it got in the danger zone. If I remember right, Mythbusters determined the danger zone for 2 liter bottles to be around 150 psi.
My students love listening to him. He explains in a way they understand and appreciate. We need more people like him and less people who just leave unhelpful comments. Constructive criticism helps us get better. Personal attacks are just an insecure person’s method of leveling the playing field by pulling others down.
I wonder how it would if the “pontoons” got replaced w/a single HPA tank and adjustable regulator?
He addresses interesting concepts in a way that makes me smile and demonstrates them in a way that most certainly will inspire others. I’m looking forward for his next project.
Another testament to the “Smash that LIKE button” culture. To each his own, I prefer science over clicks, and it’s lacking in this video.
he does videos on individual concepts, where he explains both the concept and the history of it. I only know because I just got done watching the one where he explains how the lily impeller works. he also did a whole series on tesla turbines, which may explain why he didn’t go into as much detail in this video, as he’d already covered it once.
I thought he was quite amusing and fun to watch
I was wondering why you would use a wearable Arduino as an impeller, and whether the components would stay attached at high rpm.
I think that this is an example of trying to force an initial misunderstanding to fit. But the LilyPad is the right shape so I got past step two…
I enjoyed the style of presentation (articulation and videography) and it introduced me to a couple of new topics (Tesla turbine and lily impeller). If and when I want the down and dirty details, I’ll grab a text with a different frame of mind. All in all, kudos.
Sounds like a personal problem…
I think the propeller is pointed the wrong way. Look at the direction of the wind turbine.
I was pretty obsessed with Tesla in the 90s. So before I saw the video, I thought it was going to use the turbine rotor for propulsion, Kinda like a Tesla sternwheeler. Makes! Go make that! xD
Not sure how you cope with real life, but I enjoy watching someone who is comfortable in their own bubble. Schauberger noted that Trout could stay stationary against a moving current by redirecting the water back on itself, thus causing a vortex vacuum in front of it . I’d like to see if you could emulate that.