The Stirling Engine Project: Episode 2 

"Hello, my name is John and I'm a Stirling engine addict" "We prefer the term 'enthusiast' here"

As a engineer that finished my degree about 1 year ago I am overwhelmed by your skills. Amazing.

Just the torque transducer deserves its own video. Great work!

One day I hope to have this level of ingenuity.

Very elegantly reasoned out, I enjoyed it a lot. Though I prefer the term “sanity check” to “sketchy test”. It helps me feel I am behaving more scientifically!

Your attention to detail in this project is just beautiful to watch! I'd also love to see some kind of monitoring for the total heat transferred, along with the instantaneous difference in temperature between the hot and cold side. This would allow you to calculate the engine's thermal efficiency.

I love your approach. "Why don't I just design my own?" and then proceeds to show how simple the principles are.

Stumbled on the first video through Hackaday, had just finished watching it and hit Subscribe when part 2 dropped. Perfect timing. Looking forward to part 3.

Wow! Measuring what you build is what makes this so interesting to me. So many projects simply run / show a voltage but there's no 'meat' behind it in the form of power or measurement. Really enjoying your work here :)

big fan of those intermediate sketchy tests as well helps you confirm the thing you thought was a good idea actually works.

The head actuators from old HDDs might be great donors for coil, magnets and axle to build a DIY torque transducer.

My God. Man. Hands down. Thank you for your work and sharing it with us. I'm really impressed with your work,and surprised that your channel is not over million subs yet. Cheers and keep it real!

I saw a electromotor performance testing device once that just had a flywheel and a rpm sensor. Performance was measured by looking at the acceleration of the flywheel over time. Brilliantly simple and accurate...

Wow, This is some pretty heavy stuff doc. Just remember that a bolt of lightning is gonna strike the clock tower at precisely 10:04 next Saturday night!

This is the fine art version of backyard electronics.

I have no interest in sterling engines but I KNEW there's more to it (having watched your previous videos). That torque meter is a beauty! This thing should have its own video!!!

@ 5:25 They say it is good solution, but I like your much, much more :) It's astounding project and I'm sure everyone is super pleased having opportunity to admire it. And I think you really deserve much more attention from RU-vid community.

I am very impressed, blown of my feet. Its incredibly novel, yet very well presented.

Besides the extremely useful content of your videos, I find your pitch and mood ver calming 😄! If I’m tired I’ll watch the videos to relax 😄🙌🏼

I'm a Auto technician and specialize in Electrical diagnostics and love doing it, so naturally I'm always designing and building things myself. This video was very impressive and hope to be at your level one day. I know I will. Keep making videos man, we're watching.

U have a quick process and wide range of real knowledge.. Were you.. Are u.. A professional engineer?

That torque transducer is a thing of beauty. I would probably just have used a 1m long lever pushing on a kitchen scale. And I would have attached the torque transducer assembly on the engine mount to avoid the hassle of it having to move along with the brake. Though I guess placing the whole sliding brake assembly on a tilting platform and measuring the torque there is functionally the same too.

Awesome, very nice build. That torque transducer is clever!

Wow! I've picked up a few tricks, thank you :) Found a link to you channel on the EEVblog forum. I wish RU-vid suggested your channel earlier. Great content!

Fantastic, you really have a bag of tricks!! Congratulations!!

I am looking forward to see the next stage of the project! ⚡️

interesting how electric and stirling hot air works so similar, all about changing the pressure of the forces..... whether temp or electronic differences in potential energy, all works very much the same, all energy is energy, and seems to work the same in so many ways. thank you for this video, and the thoughts it made me think.

Very impressive range of competence /madness. I would not like to think how many hours of work this covers.

I love your Artisan but scientific approach!

Hi Leo, never thought that you even go to the extend of creating your own torque transducer. So much work go into that. Nonetheless, congrats on your progress and look forward for part 3.

Been interested in Stirling cycle since being an apprentice mechanic in the 70's. tried building one as a Technology Teacher around 2010. Close but no cigar!

Pure engineering! Love at first sight!

You got me, I have to build a Stirling engine. Got it. Understood.

Get on patreon! Leo, your skills are under appreciated. Start winding your generator motor! Another way to measure the raw output power

Wauw...much respect! Really perfect done...will certainly look epi 3😇💪👍

To be efficient, the working fluid in a Sterling engine is hydrogen under very high pressure. These two factors present formidable challenges in sealing the the shafts driving the displacer and power pistons.

Please, keep making these videos, I absolutely love it! I'm a Physics student, but actually I want to be an engineer, because I love all the plan & build part, so your videos are a big pleasure for me

Great to see the smart application of analogue circuitry where it really belongs. Too often high powered microcontrollers are put to use them it's not appropriate

I learned a lot about things i wasn't aware of. Thank you.

Enjoyed, learned, and impressed as heck. Anticipating episode 3. Thank you Leo.

Fantastic work Leo.

Look into using a Diode Heat Pipe to keep the hot part hot and the cold part cold. Also, don't bother trying to correct the imbalances in the crankshafts, and just focus on perfecting the cylinder. Eventually once your piston and cylinder are perfected, you can move on to building an Inline 6, a V12, or a Boxer 12; use either of those engine configurations, and your imbalance issues will just melt away. I'd love to see a fusion between a Stirling engine and an internal combustion engine. You could get the best of both worlds.

Wow! Absolutely incredible level of both detail and engineering.

Happily subscribed for episode 3.

Your knowledge and attention to detail with this project is incredible, I'm looking forward to the next part!

That is an amazing solution for a small dyno, hope it works well. Do you know the energy output of your butane torch? Might need an electric hotplate coil or induction coil as the heat source so you know your input energy and can calculate your efficiency. The torch my be outputting up to 800w of energy (probably 250-500) and if your sterling is even in the 5-10% efficiency range you will be making well over the 11watts that your dyno can measure.

Can't wait for the next one

Very nicely built device! It's clear you have a vast knowledge. Awaiting the test of your Stirling engine!

for the support

Nice, it turned out excellent. I love how you as an experienced engineer rather test something early on to get a good idea, which is what I personally prefer as well. However most companies (and schools) rather have you calculate and simulate for a week, just to find out that the results are outdated before they were announced, because some little detail was not in the equations. Looking forward to part 3. Greetings from Germany, Michael

For low rpm spin thr magnets with a small motor and subtract the difference of the steady state motor.

Great job! I intrigued and had to subscribe to see the next episode!

Bloody good stuff mate

part 1 was a nice build on a simple ? engine design, then part 2 was very impressive with your thought process and developing your own sensor setup while saving alot of $. ocd rules

Hi, I like the design very much, I never thought one could 3D print a functioning Stirling engine that works so well! 😜

Funny when you mentioned the obsessive nature of interest in the sterling's it resonated with me. i have been fascinated by the sterling generator idea built by NASA.. as im interested in solar power being used to generate electricity with a sterling as apposed to panels. I think your test torque meter is genius and you gave me a few ideas as to testing using that method (and i have a 3d printer)..I look forward to your tests. cheers smarty pants!

Next level bro, wow.

Amazing work. Reminds me of what they do in Cuba to continue innovating to survive. Put out a product for me to purchase so I can support!

Very impressive!

WOW! a pretty comprehensive study of the torque curve. Real nice work, I'd been satisfied with an ammeter across some headlights. Ya your doing real nice work. liked subscribed. The ability to easily burn propane/NG in a generator is handy because the fuel wont go stale. Air traffic controll has this problem frequently in there generators, this engine has a lot of feature's like that.and the veriety of heat sources endless. your hard work has great value to me. Thanks!

Really interesting stuff !

I saw a very simple dyno recently that was nothing more than a torque arm with a point contact onto a set of digital scales. That could be automated very simply with an electromagnet controlling the amount of drag on a flywheel.

Can't tell from video what material the backing plate for the eddy current magnet holder is, but each side should effectively be magnetically similar to an open ended U magnet facing the aluminum dynamic plate in order to maximize the field concentration through the aluminum. Easiest way to do that is for each end of the stationary magnet stick to have a north and a south magnet roughly near each other and for the plate to be steel to allow a return path through the stationary plate.

Defiantly worth a SUBSCRIBE.

Great stuff going on here. You earned a sub. BTW, I found you while searching 'free piston stirling engine'.

Good call on the LED as a detector. I'd have gone with a gradient on the blade myself, a wide grid that got selectively filled in until totally filled in the center, then selectively filled until totally empty at the other edge. But an LED is less finicky I think.

I'm wondering nowadays with more lasers available to cutting... if Ruby would be easier to have cut or maybe in another way I have no clue regarding... depositing on to the cylinder and piston. Seems would still need like an air bearing lathe or grinder to somehow make smooth the Ruby cylinders for the least friction. Hope I'm correct thinking ruby lined cylinders and I think lined piston as the holy grail of material also since has been a while since I've researched. I recall whatever NASA paper that was I read about regarding and haven't been able to find since... noted increasing the pressure of the working medium (fluid) that improves efficiency. Seems there were some capacitors on the market that disappeared too that used ruby... though for like maybe really low Q or something I recall reading maybe in the last decade. Awesome series! Thanks for sharing. Subscribed.

The level of precision you need for placing strain gages is unbelievable. I worked for a company making torque transducers. I designed the signal conditioning circuits which was also a game. I would advise not going there unless you really know what you are doing with the bridge balancing.

So glad I discovered this channel!

Great video!

Amazing series of video, thank you for making this and sharing your knowledge! I'm interested in your "simple TTL circuit" that you used to create your crank speed sensor, would you be able to share your details on your VR conditioning circuit please? Thanks!

Thanks for sharing you knowledge.

Wow, I just realized how incredibly stupid I am. Not stupid enough, as I realize there is a potential use for a Sterling engine as a small home generator if coupled to a pellet stove and battery storage system like a Powerwall. If you can scale up your Sterling (absolutely possible) to a 100 Watt output, this would be feasible for people in remote areas when the stove is running 24/7 during the winter.

the simple linear ps option see 'HomoFaciens Rotary encoder or: How to build a digital servo using an Arduino and photo sensors'

Great video! You are very skilled and knowledgeable, I'm glad I found your channel!

This. This is fantastic.

Wow 🤯, I glad theirs clever guys about

Dude. Puts me to shame!!! Honored to find your Channel.

Cant wait that you will make a 300 watss machine.!!!

Great video, very interesting. I really like what you do, continue like this!

Amazing

Thank You! Great stuff.

Wow you do have a bag full of tricks! You are amazing. I'd be concerned about the dynamic response of the torque meter, it will be as good as your closed loop controller rejecting the ripple in the misaligment measure , probably you will have to augment the bandwidth in the close loop to get better results, anyway for this application at high angular velocity an averaged torque value is good enough. Can't wait to see Ep. 3

This is really awesome stuff. I just finished my phd in microscopy and optics but want transition to more engineering and Im learning so much! I love it :)

It's back!

You are killing it bro. Keep it up.

Very cool, but thinking an electric motor used as a generator and measuring watts would have been more effective... Thanks for sharing though

Very cool! Obviously doing it this way you're going to have more "real world" info about the engine output, but couldn't you more easily measure your efficiency backwards by using a motor to drive the engine and measuring the temperature generated at the hot end?

I saw your first video and liked it but didn't feel compelled to subscribe. The detail you went into seemed repetitive and unnecessary. It was a nicely done presentation, so please don't get me wrong. Then I saw this episode where you earned Uber maker status by creating that torque measuring device, but didn't stop at just throwing things together, you were diligent to shield the position sensor beyond the call of duty. Most would just have cut up an aluminum pie plate and used hot glue and duct tape. So that being said, you earned a subscribe from me. Because such dedication is a high order qualification for me to keep watching. Thank you. Bravo.

You've got another subscriber! Keep this project (and others please) up! love it!

Ohh boy, you really need a patreon page! Hope you keep doing this awesome stuff!!

looking at the diagram i at first thought that the stepper spun the whole thing counter to the engine rotation to get around the low speed eddy current brake limitation

You are an awesome engeneer Mr Leo😍🤩

great stuff!

12 steps to intelectual bliss

Amazing ! You make it look like it is a piece of cake ! How many hours invested in designing/building/testing the transducer ?

Next episode we are making the life size Death Star with stuff on hand.

Awesome Engeneering! A PID-Controller for an electromagnetic force actuator was part of my university class last semester. It was interesting to see it finally implemented and not just as a task from a textbook. Have you done the PID-Controller the analog or the digital way?

you could actually use the concept below to get variable braking and eliminate the slide

great content. thank you