As a retired machine designer, I've seen a lot of machinery that used rollers in tracks - I've even used this in some designs in the past. But, these are extremely wear sensitive and when they start to wear it doesn't take long to have catastrophic failure. Nothing is simpler, less expensive and longer lasting than rotary or pivoting bearings. Plus there is still the CO2 emissions that cannot be eliminated when burning a hydrocarbon. H2 is extremely energy intensive to produce, transport and use. Also, using it to replace petrol fuels is very inefficient compared to using it in a fuel cell. Someday, H2 may by practical, but I've been following this for over 50 years and nothing has proven economically feasible yet.

The only things that matter today are: 1.) emissions 2.) durability at least 150k miles or 10 years 3.) Fuel Economy - at minimum 25% better than the best of piston engines 4.) Lower production cost per unit than established engines IF all 4 are not realized even in low volume production, then the design DOA

Hybrid electric vehicles have always seemed a good option to me. Most driving is done around where you live. Extended trips are not the norm. Having enough battery capacity to cover most around-town driving, with an efficient single-purpose fossil fuel generator to cover extended trips, is a good way to ensure range, decrease weight, and lower the cost of a pure electric vehicle.

You missed the Commer TS3 truck engine, with three barrels, six pistons. The sound they made when driven hard had to be experienced to be believed. The machining had to be absolutely accurate, and the complexity of cranks and double ended rods meant they became prohibitively expensive, but they made glorious low profile engine for powerboats. Thrilling acceleration and a cockpit the size of a ballroom.

Fairbanks-Morse diesel engines of the 1930s and 1940s as used on many ships in the US Coast Guard and US Navy during WWII were of the inline, opposed piston design and were a two-cycle combustion series. The biggest issue that we had with those engines was coolant jacket leakage into the combustion chamber where the fuel injectors were mounted. The injectors had to pass through the coolant portion of the cylinder liner assembly and on into the combustion segment of the liner. This issue with coolant leaking into the cylinders was a chronic problem that we had. Otherwise the 12 cylinder units were basically good engines. Fairbanks-Morse diesels were available in many different cylinder counts according to requirements. These were not clean engines by any means.

The Napier Deltic engine makes a beautiful sound. Luckily some of the locomotives that use these engines survive.

Thank you. Your summary along with the graphics shown helped even a nonmechanic like me understand. Thanks again.

I and my cousin brother thought to build like this one 4-5 years back but couldn't because of financial constraints this engine can also be used in series hybrid where two generators can be attached one on each crankshaft for range extender purposes.

Never heard of this type of engine until now. Fascinating. Terrific animations.

My father retired from Motorola in the early 2000's , and told me that power electronics seemed a very promising maturing technology. PE's are crucial to the implementation of hybrid ICE/electric automotive platforms, which benefit from using the electric part to eliminate heavy and inefficient drivetrain components. Electronic control, both power and non-power, allows a high degree of variability which enables an ever more adaptable range of usefulness for both parts of the ICE/electric combination. Batteries and access to sources of electricity are both significant constraints for pure EV's, and are where hybrids gain value in their practical implementation. From an engineering perspective, electrical, mechanical, and chemical (combustion stoichiometry), these are very interesting times, indeed. Great video!

well done, you're the first person Ive listened to realise those two "wobbly things" are cams

The problem with this engine is that it lack of low en torque(I mean, like a lot). Also, the 120hp isn't made from a N/A engine. If you look in the Miata video, there was a supercharger

Early in this video you parrot the designer's claim that this is a 1-stroke engine. Look again. Each pair of pistons do come together at TDC or compression-delayed/adjusted TDC before combustion, validating them as opposed piston arrangement. However, each piston ALSO must move 2 directions between firings. Intake and compression on 1 stroke, then combustion and exhaust on the next. Simply having one of the combustion chambers firing every time a piston pair reaches TDC or BDC does not make this a 1-stroke engine layout, otherwise a 4-cylinder 4-stroke could be called a 1-stroke engine since each 180 degrees of crankshaft rotation there is a combustion event. This is truly a 2-stroke layout and still really cool. I love the adjustable compression ratio they've incorporated into it.

Thanks for telling us what people are trying. It would be nice if there was a way to beat round cylinders and a crankshaft, but by looking at them, I don't believe either of them are going anywhere. - The swash plate/cam track configuration is a non-starter for the reason you mentioned. - The opposed with the crankshaft will fail in fuel efficiency and if it passes emissions it will be due to external help. The once-popular design lost out due to fuel efficiency issues to where few are still in use today. GM's old Detroit Diesel Series 71 engines would be a more efficient design and could potentially be cleaner. - The Wankel hasn't been competitive. - Turbines need to work in a relatively narrow power band to be efficient, and even then they are a long ways from being comparatively efficient. The best attempts for cars have been the Chrysler turbine car and Ford an H-Series truck which used ceramics to enable higher heats. One would think it could make it on trains but they couldn't make it there either. They make it where fuel efficiency isn't the issue, steady high loads, and/or weight. The only ones that dots most of the Is are aircraft, starting with helicopters which work much harder than airplanes for the same weight. High-horsepower piston aircraft engines have such maintenance and reliability issues that it turbines make sense earlier for weight, reliability, maintenance, lifespan, altitude compensation, cabin pressurization and heating, etc. What could change is the availability of cheap energy to where efficiency is less of an issue. Electricity is very inefficient unless you can make it an transport it inexpensively. The U.K.s idea to use many Thorium-based plants would help. It could make hydrogen fuel less expensive as well. (I often tease a customer with a Volt, "I see you drove your coal burner today.")

The swash plate pump and motor have been around for decades in hydrastatic transaxles on lawnmower. They have to turn extremely fast to generate useful torque. Have ever seen how fast a riding lawnmower is.

Still think the LiquidPiston concept has better odds of making it to large scale production. Plus the thermodynamics of the LP rotary yield a considerably reduction in specific fuel consumption. Larger version of the LP engine can be achieved with either larger rotors or by stacking together multiple rotors. The OP concept looks like it can only scale up by making the pistons bigger to increase displacement with the given number of pistons. This will make the engine larger in diameter, which is the exact opposite of what you want if this is ever to be used in an aircraft.

Wow. Someone took an old (like 1960s) GM swash plate air conditioning compressor, split it in half, moved one half so the piston tops face each other, and made an engine of it. It seems to me the major advantage of this arrangement vice just making a six cylinder engine from the GM swash plate compressors is the ability to vary the timing of the two swash plates. The supercharged Fairbanks-Morse opposed piston engines had six degrees lower crank lead, the one with turbochargers and supercharger had twelve degrees lower crank lead. The lower pistons would clear the exhaust ports earlier so the exhaust could spin the turbos.

I refreshed my memory from my time in GM Training, the radial air conditioner compressors work quite similarly to 1 end of this engine design, we all know that an a/c compressor can last the life of the vehicle with minimal maintenance/attention, I think with a little different design to the cam track set up, this could be a feasible option for the ICE as a generator engine

Hi. Internal friction from four extra pistons with rings will negate any advantage from losing the friction from the crankshaft and valve gear. Sliding friction is much greater than rolling friction. One step forward, two back----. Cheers, P.R.

I love the idea of an OP range extender.

I‘be always loved the simplicity of 2 strokes. This model looks very “cool” but what about the cost of fabrication and then maintenance. Just machining those parts looks technically challenging.

The camp voiceover is hilarious, please keep this 😘

i'd like to know how any of these are getting around the problem of piston rings crossing the intake ports & either drawing in oil & burning it (smoke & emissions) or wearing the rings & needing replaced/rebuilt. That is the same issue 2 strokes end up with. Once i figure that out i've got a couple designs for 2 stroke positive displacement supercharged direct injected engines that would still utilize exhaust valves/cam in the head with bottom dead center intake ports supplying pressurized air at a 1:1 ratio or higher.

Cummins developed opposed 4 cylinder, basically a flat 8, but with 2 cranks and 2 stroke. Maybe there is hope for engines with character. Cannot wait to hear one.

Great video.. The first to see an INN actually running and throttling up (with or without intake boost). By the way, don't lithium ion battery chemistries come mostly from the refinement of sea water?

The roller in tracks design makes a very compact engine, but I believe the Achates engine is probably the best design. Using the transfer gear as a power output, it can even have a built in gear reduction making it a great option for small aircrafts and boats.

Do you test any external fired sealed combustion Chamber Engine

Cam track? On paper it looks neat. The load bearing surface interface between the piston roller and cam plate will be difficult to make reliable. High pressure oil lubricated shell bearings, as used for crankshaft journals remain the most robust and inexpensive bearings to support the rotation of reciprocating engine parts. A single roller on a single surface wont cut it. The engine would need to drag the piston down to ensure it would start.

I have been thinking of something similar for over 40 years. Now that the internet is hear I can actually see it

As a tech with some engineering I would love to learn specs, but I did enjoy your video

Interesting, looking forward to driving with it

INN will probably take years if not decades to proceed beyond prototype stage. Longevity is a hugely critical issue, how will the motor respond to a backfire or low-octane pinging. How reliable is that swashplate concept, and how sensitive is it to the quality of lubrication. I'm also curious if it's not possible to stagger the combustion events for a smoother output, perhaps if they went from 4 piston pairs to 3 pairs they could reduce part count and improve smoothness (the MX5 video sounded very "raspy"). I have an inkling that efficiency (and emissions) could be improved quite a bit if they incorporated a catalyst and turbo: there will be unburned products of combustion in the exhaust that could be completed in a catalyst and the energy captured by a turbo. Interesting prototype.

Engine maybe useful in military applications as part of a power pack for a future hybrid Bradley replacement.

Recent subscriber, interesting topic, we need something that people can drive/use who cannot afford EV's. As we inch closer to 2030, the cost of EV's will only continue to increase, here in Australia... there are nowhere near enough charging stations. My main concern is that people will simply be priced out of new car purchases on one hand, and on the other hand find themselves 'punished' by the state for continuing to drive their aging 'polluting' vehicles which they cannot afford to replace.

This is "Tech Anxiety." All these great ideas and inventions and nothing seems to stick to the wall...so to speak. I'd love to see these innovations in my car, my plane, boat. I'd love to see an OP engine or a liquid cylinder engine replace the relatively inefficient four stroke engine. I still don't know why we don't have a small engine running an electric generator for electric cars. Where's that idea not used?

So whats the effiency? Over 80& ?

As a longtime fan of both Tony Seba ("Clean Disruption") and Amory Lovins ("Reinventing Fire"), I think you are underestimating the speed with which the green transition is happening. However, as a Chevy Volt owner, I can attest to the excellent utility of a "range-extended" EV. I tend to get a lot of guff from my fellow EV fans for advocating long-range PHEVs as a setpping stone for legacy OEMs who are struggling to make a pure BEV that they can sell for a profit. But with a 10~15 kwh battery pack, you can easily get 40~50 miles of pure-electric range, which is more than enough for most Americans' average daily commute. (I drive about 25~30 miles a day, and I haven't burned any gas in months.) This gives you the efficiency of an EV with the long-range convenience of gas. Combine that with one of these new lightweight engines you're talking about, and that would be an attractive package to a lot of people who are still a bit worried about range anxiety.

Differently designed & complex moving parts makes this machine more vulnerable to mechanical failures. It will never be a challenge to EV at all.

Nice if it is light and powerful, however you cannot get excessive gain in efficiency as it is still based on the carnot process. Absolutely correct that a plug in hybrid should use the combustion engine (of any type) only to produce electricity. This allows the engine to work in its optimum working point in terms of efficiency. I would assume a battery capacity of 15 to 20kWh to be enough for a plug in hybrid. This should reduce the battery weight compared to 60-80 kWh about 180 to 260kg. If you refrain from moving a 2 ton vehicle at constant speed above 120 km/h this give enough weight reduction to install the combustion motor (and fuel tank).

What is your opinion on the 4 sided rotary quasi turbine??

You forgot the knocker engines used in England for years in large trucks. It was a 6 piston 3 cylinder supercharged diesel

The Napier Deltic ran at 1650hp in trains, that's not where it 'topped out. The turbo compound Deltic ran to 5600hp in a destructive test.

Looks like it would work really well in a Gyro copter.

Putting gear teeth on the swash plate and rollers would eliminate problems with the rollers skidding on the swash plate which would improve efficiency.

Very interesting and well done. Thanks!

The 3 cyl OP design is probably one of the best. The development of a hydrogen fuel system paves the way for another breakthrough efficiency technology to be integrated into the engine: Paul Pantone's fuel reforming plasma reactor. Simple in design, the device simulates a lightning strom inside of its body by passing hot dry gasses over cold, moist air in a turbulent and magnetically active arrangement. The end result is a continuous plasma spiral lightning discharge in a vacuum, through which the atomized droplets of fuel pass, to be molecularly reformed into a synthetic hydrogen gas. This enables almost any liguid to be processed into synthetic hydrogen, including all types of fuels and even water. The resulting combination of an effiicent hydrogen injected engine, and a flexible fuel reformer for turning any fuel into synthetic hydrogen, will allow current technology to achieve super efficiency and near zero emissions without the need for massive mining of rare minerals to support the transition to green energy.

Very good information on the opposed internal combustion engine. We have been dependent on the IC engine since Otto invented it in 1840's along with the steam engines that are all mechanical devices. Petroleum is the most efficient highest density fuel on the planet and it is continuously produced or comes from the core of the earth; atomic reaction to heat that condenses and condenses...... to gas that condenses and condenses.....to liquid and as it rises from the pressure it does collect minerals from the earth, and as it condenses and condenses ......to solids and you have carbon, coal and diamond. The future and it is in its beginning stages is the fuel cell that produces electricity from Hydrogen. When hydrogen is compressed it is a more energy dense fuel but with many other challenges and costs. This fuel cell technology will develop into a similar converter that actually does the same as the fuel cell with hydrogen but will directly convert or strip the "carbon" of its excess electrons. This is a carbon planet and is what we all run on as a low temperature carbon oxygen engine; our bodies. This IC engine has been great but very inefficient as the gas Otto engine is 25% efficient the Diesel engine at 31% it is wasting the balance of the carbon/petroleum potential into the atmosphere via the radiator, exhaust and heat radiation. So the next generation converter will take petroleum/carbon and strip the electrons of it via this fuel/matter converter and give us a 98% efficiency and zero pollution as it doesn't combust the petroleum as in the IC engine or reaction engine. Rudolph Diesel came very close to exposing this device in 1900 after he developed the compression combustion engine but he disappeared off a ship he was on way to delivery his findings to others. No need to say but this technology was not wanted to be exposed by ? I do feel the "range extender" with a small efficient power plant is a great compromise or extension to the electric battery. So much more to say. Oh well. Well done on bringing the "Opposed Piston" engine technology to the forefront. I am impressed with the "Liquid Piston" advanced Wankel engine with 3 combustion cycles per revolution. Thank for your info and well done on your research and KZfaq presentation. Wm

If efficiency is indeed great, is it?, then maybe useful for range extenders in heavy vehicles running on E-Fuel.

I rate this the same about solid state batteries in development. Hype. Tony Seba told the world in 2014 what was coming. Big Carbon had its chance but they locked up IP and solar will be surpassing coal next year. The batteries produced at scale are working now. The cost curves are dominating now. No hybrid strategy will scale fast enough to bring its costs down when EV's require less parts to make especially with gigacasting the fronts and butts. The TCO is compelling now.

Fascinating that No One is Talking About How This Engine Can Be Used With Alternative Fuel, Like Hydrogen Or Propane . . . Forget About Batteries!

If I drove truck as an owner-operator, I think I'd be willing to take a 45 minute break every 7-8 hours if it cut the cost of fuel & repairs significantly. This should qualify as one of the mandatory breaks anyway. 5:00 However I still like the look of this engine for marine & air applications or trucking outside the super-duper-charger network (or whatever it'll be called).

I see this engine as a new way to explore the electric car. It could be use to power an electric car with very limited batteries, and could turn out to be very economical, and offer extended range on very long trips. Generator driven diesel electric locomotives have been very successful for far too many decades to mention. This little engine is so light that it is what is needed for our future hybrid cars, as another alternative to the battery plagued only EV concept. Always keep open mind and try to avoid fads that might give us what we want, but in the end it may not be what we need.

The Blower thats mandatory for this 2 stroke opposed piston for scavenging air. No mention of it at all!

If we look at the "use case" scenario for long-haul trucking, a truck operated by a single driver can only drive for x hours (10 I think). Whatever the number, a driver has to sleep *sometime* at least. That's a perfect match for a charge/drain battery cycle. So small range extenders can be used when there is no electricity to charge while resting. Also, super capacitors have quicker charge rates so that could be useful. They also have quicker discharge rates so that has to be managed in the system design. My point being that some combination of small range extenders (especially for at-rest charging), super capacitors, and slow discharge batteries of some type will probably be a good configuration for EV long haul trucking. BTW, it would be great if could you do a video on the latest EV power system designs using these 3 energy sources. Thanks!

Using vehicles that run on electric motor and battery strains our economy and does finally result in a larger carbon footprint than an efficient fossil fuel vehicle. Batteries should be used in hybrids and made to last 15-20. years. We had a British design in Delhi, IN and it was superb (2010...)

How much mechanical friction is generated by this opposed piston system, in comparison with the standard ice motor?

Interesting. Thanks Ellie.

The Achate seems a winner. If it could be reduced to something of 20hp it would be a fantastic outboard engine. Also with 16 hp a hybrid could make a car last much longer. Electric motors on each wheel. Drop the bendix starter and place with proper gearing an alternator- motor that could smoothly start the Achate engine when needed. That would be my dream vehicle.

When I first saw the Opposed Engine, I was so excited about its principle. Moreover, five years ago, I translated a video with a voiceover about the Achates OP Engine into Russian and shared it on my channel. The company had just introduced their prototype to share the idea and concept, but you can't even imagine how much hate the "couch's experts in this field" wrote in the comments below in the end...

I have a limited knowledge of engineering. I can figure out how the rod can push the apex designed flywheels. Perhaps if it where modified to a specific direction and were six pistons. The pistons would have to be in seperate sleeves for efficient combustion.

Imagine throwing a rod on that thing. Flies straight out the block through the car because all that’s in the way is another piston and case. A lot of design are great when something is working the way it’s supposed to, working on that looks 100x more complicated than a straight block or even a v type.

It could be run on wood gas from a pellet pyrolysis setup. Wood pellets can be made from scrap wood and wood waste. So, you'd have a hopper rather than a tank. It would also be possible to carry the equipment with you to convert wood waste into pellets. That would add weight though. I must try this out some time.

Lubrication mechanism video would be nice to see for these engines.

Any idea how this engine compares to the "K" cycle engine?

I gave you your #300 Sub! Congrats!

Feeding the KZfaq algorithm. Informative video. Thanks.

I love this concept the only questions I have is the efficiency! It's better than liquid-piston new motor with 45%? /Mikael

This type of engine is already common in waterblaster pumps. Waterblasters suffer failure if the water is disconnected, I wonder if this engine will cope with abuse as in missing gears, etc....

Swash-plate engines have been around since at least the 1920; they can be extremely reliable if not necessarily high performance. Often used in industrial situations where a constant RPM is desired - they might well be ideal for a hybrid.

And making cars like trains I have been thinking about that for the last 30 years I road a golf cart for the first time and my mind was on it about making a car and Gen set !! Glad to see it coming to life !!

I too like a design I feel that it should be able to charge the battery that is made with if it comes out with that design I believe it should be better on its own can't wait for them to crack the frictionless metal miracle

Oh this is wonderful. With my EV I was really missing having to go to gas stations every week, and don't forget about the oil changes every 5000 miles. How did I ever get along without a mechanic trying to upsell me an unnecessary brake and coolant flush for just $69.99! There is just nothing that can substitute for hundreds of moving parts with contact points of wear. I also was getting a little too comfortable not worrying that my catalytic converter wouldn't be on the car in the morning. And let's not forget about that badly out of tune car exhaust smell that's just like fresh geraniums.

I have a Chevy volt and love it I would love a one ton electric with a range extender.

How is it cooled .

Great video bro, thanks.

That small one would be fun on a long-tail Thai race boat.

The reveal of this engine is interesting, however the flaw with battery power that nobody is talking about is safety. For example third rail electrical trains use high voltage DC power similar to cars. To work on a railway there's a lot of health and safety involved. We're giving a similar technology to the public in battery powered vehicles, however the public crash and regularly misuse and damage vehicles. High voltage DC is dangerous, the public are unaware of the potential dangers and rules that must be adhered to.

A healthy evolution of vehicle propulsion. EV automotive tech is driving significant advances in ICE design. Both of the featured engines are great potential range extenders in future hybrid electric drive systems! I really like the Achates design.

It would be nice to see it on small leisure crafts and marine applications.

There is an FAA approved cam track engine that generates 400 horsepower from the 60’s or 70’s. I believe it was called the Dynacam engine and I’ve seen it run with a huge fixed pitch prop on it. That was in the 1980’s….

Besides other issues, it would not take 45 minutes to charge, unless going from empty to full, but that would likely be rare… Also, how long does it take to load, unload to head out? I have seen videos of drivers waiting hours because the logistics are not really setup to be efficient.. so instead of idling for an ICE semi or just sitting there doing nothing for an electric semi, it could be charging… Put solar panels on the facility (assuming warehouse/distribution center) and use that power to help charge the trucks.

Apart from Tesla there are a few other EV semi trucks out there. In Australia they have semi trucks with a battery swap that take a whopping 5 minutes and they are PV charged as is the forklift that does the swap .

The working prototype clearly has a mini supercharger inside the engine bay

Kirk Sorensen, in posts on this site, proposes use of hot nuclear fission to break down water, then use of the hydrogen to form fuels to replace diesel and gasoline, carbon-neutral. If that can be made to work, it seems less destructive than use of Li-ion chemistry and so on.

What keeps the rollers stuck to the track? What happens if fuel runs out? I also wondered if cylinders need to be round, or if they could be kidney shaped, to take up the available spacing, increasing volume and produce more power.

The torque is great suggesting larger engine power in smaller packaging but is it reliable 🤔 😳

Sir consumption of fuel?

All good, it's just needs to used a non - carbon fuel and it will be a winner. Less emissions is not zero emissions, it will still require oil drilling and refinement to make the fuel. The goal is to transition away from carbon fuels, not just use them less! 👍Like i say nice design, it just needs to use a clean fuel!

Excellent video 👍

I noticed there is no mention of the efficiency of these new engine designs. To be economically competitive with my BMW I3, the overall thermal efficiency will need to be above 85%, and there's nothing on the horizon which suggests a combustion engine can achieve anything close to such a high standard.

Its like...holding on to prop plane when jets came alone.

Is exploding rare fossils still a thing when we know they are atrociously inefficient?

it's not too late for development of new engines, because resources don't allow for 100% electrification of road transport so whoever has efficient alternatives will do well. A good contender which uses much more proven tech is a constant speed micro-turbine engine with an electric drivetrain, because then the traction characteristics of the motor overcomes the turbine disadvantage of low starting torque. Incidentally, the Napier Deltic engine was a fine design which was abandoned by cash-strapped British Rail who were left with multiple non-standard engine designs as a result of their own rubbish procurement policy for locomotives. The same unit was used in its original intended role in the Royal Navy's Hunt class mine warfare ships, where they remained until re-engining was completed in 2018.

I wonder if a scaled down one would work as a boat engine in a hybrid application. I like the idea of electric, but I wouldn't want a totally electric yacht. It's too dangerous to be offshore with only a battery and solar to get you out of harms way in case of storms. Having the option of a diesel engine that also charges batteries would be great

Enjoyed your comments! Why not refuel Semi trucks on the GO like our fuel tankers refuel planes? Trucks could continue running at 50-60+ MPH while a lead battery truck is charging, """MOBIL REFUEL STATION"

Norway transferred over to mostly hybrid‘s at the end of the 1990s, but now 85% are full EVs which identifies the most favorable direction for transportation. Certainly not hybrids, which was the best we could do in the last century. I EVs are by far the simplest and the only option That allows us to eliminate blowing toxic fumes in each others faces.

Great Idea !

Lubrication of those ?

As a range extender for EV's it might be a good fit. But for use as a single source powerplant, I don't see it. It is going to need a turbo or supercharger to create the torque needed to overcome the friction of 8 pistons. At this point, I think they need funding to continue their R&D. I think, that is what all the positives are about, found in the news so much lately.

IMHO... I believe PHEV is the way to go, pure Electric will never be the answer. Using electric for stop and go city commutes is very efficient and would reduce the smog in metropolitan areas. However, gas is the way to cruise at highway speeds. I owned a 2017 Chevy Volt PHEV, and now a 2022 Kia Sorento PHEV. Both are very efficient, with local commutes on pure EV and upwards of 40mpg when on highways. That being said, I added a gas engine to my 2015 Electric Smart fortwo to make it a PHEV.