
Aquarius builds an engine others only dreamed of - rmason
https://www.haaretz.com/israel-news/.premium.MAGAZINE-a-little-startup-that-could-aquarius-builds-an-engine-others-only-dreamed-of-1.8984355
======
Animats
There are about 15 free-piston generator projects. Toyota had a prototype in
2014.[1] Here's one from the UK in 2016.[2] It's a more reasonable idea today
because switching power supplies are so good. You're going to get variable-
frequency AC out of the thing, but converting that to something more useful is
easy today. Also, using the generator windings to start the engine is easier
with current power semiconductors.

You have to have electrical control on all the valves. There's no camshaft and
no place for one. Electrical control of engine valves has been a dream for a
long time, but the actuators were a problem. Someone finally built a working
engine in 2018 with total software control of all valves.[3] The valve people
say "Electromechanically, you could look at it and ask 'why didn't you do that
20 years ago? The difference is in the electronics that control it. What's
happened in the recent past is that there's now sufficient processing
bandwidth at a low price that can tolerate top of engine conditions, so you
can actually put real time control on top of these motors."

This will probably all work commercially about the time everybody switches to
electric cars.

The parent article is lacking in solid "why ours is better than the other
people who already did this" information.

[1] [https://www.roadandtrack.com/car-culture/a6326/out-of-
turn-t...](https://www.roadandtrack.com/car-culture/a6326/out-of-turn-toyota-
engine/)

[2] [https://youtu.be/u4b0_6byuFU](https://youtu.be/u4b0_6byuFU)

[3] [https://newatlas.com/camcon-digital-iva-valve-
system/55827/](https://newatlas.com/camcon-digital-iva-valve-system/55827/)

~~~
rasz
>"The difference is in the electronics that control it. What's happened in the
recent past is that there's now sufficient processing bandwidth at a low price
that can tolerate top of engine conditions, so you can actually put real time
control on top of these motors."

is something a non EE person would say about another branch of science he is
totally unfamiliar with. We had 40GB consumer Hard drives 20 years ago. 20GB
per platter, 7200 RPM. Now think for a second what precision of timing you
need in a hard drive versus mechanical engine. We are talking ~50 nm/bit, ~250
nm/track, ~100K TPI, >500Mbit internal transfer. The level of precision
required to control engine valves more accurately than mechanical means (cams)
was achieved in consumer off the shelf ~$200 hard drive controllers around
1995.

~~~
Animats
That was a quote from the CEO of the company who makes the thing.

Fast precision proportional valves for ordinary compressed air have been
available since the 1990s. I once had to price some. Price was over $1000
each. They're now a moderate volume product from Festo and others, and
precision positioning of pneumatic cylinders is available. It's still not
common.

Automotive valve actuation has all the same problems, plus pushing back
against big forces from the combustion process and operating through the
entire under the hood temperature range. A solenoid-type actuator for this
needs considerable power. Schemes with pneumatic and hydraulic power to drive
the valve have been used on some race cars. Plus there are little problems;
neodymium magnets start to weaken around the boiling point of water, a
temperature easily reached on top of an engine block.

There's now a supercar using this technology.[1] It may filter down to less
expensive vehicles.

It's an obvious idea that turns out to be quite hard to make work. Study
guide: [2]

[1] [https://cecas.clemson.edu/cvel/auto/systems/valve-
timing.htm...](https://cecas.clemson.edu/cvel/auto/systems/valve-timing.html)

[1] [https://www.freevalve.com/](https://www.freevalve.com/)

~~~
rasz
I fully agree with everything you said about this being a big electro-
mechanical challenge, but the dude pointed squarely at the controller with
"processing bandwidth...real time control" quote.

~~~
Animats
If you approach the control problem the way a modern programmer would - read
position sensor, adjust actuator current - you need some control loop running
at some speed like 100KHz or higher. Probably doing floating point
calculations. So you need a powerful CPU.

If you didn't have that, you might have to do the valve fine position control
with analog hardware controlled by the digital system. That's how daisy-wheel
printers controlled the daisy position. And you might have to have hardware
timers for triggering events, like SOiC systems with PWM drivers. That's what
you'd probably do if you were making a million cars.

If you're making 300 supercars, just throw some very fast CPU at the problem
and let it do all the work. You'll never see the extra $20-$100 or so per car
in the sticker price of a supercar. You can get hardware for automotive
environments with that performance now. 15 years ago, you couldn't.

~~~
rasz
>modern programmer would - read position sensor, adjust actuator current - you
need some control loop running at some speed like 100KHz or higher. Probably
doing floating point calculations

Modern programmer would make sure to do those floating point calculations in
an ISR too ;-). Cars have been fine with lookup tables and interpolation. If
you can precisely control spark, you could valves as well.

As for hardware requirements. Afaik control always outraced controlled
business end. Lets take Honda for example, all their ECUs from 92 (P05) onward
had full facility to drive individual coil on plug, but officially Honda
switched away from mechanical distributor in 1999 (S2000?). You can trivially
convert 92 car with a small adapter board, ECUs shipped with all the needed
hardware sitting unused for 7 years.

------
hristov
They did not talk about oil and how it lubricates itself. Only that it
magically does not need oil changes. It is a two stroke engine and two stroke
engines do not need oil changes, but that is for a very bad reason,
environmentally-wise.

Two stroke engines do need oil changes because you are supposed to mix in the
oil with the fuel and they just burn the oil and get new oil when new fuel
comes in. This is very bad for the environment because burning lubricant is
very bad for pollution. It is also costly because you have to pay for much
more lubricant.

Perhaps Nokia figured out that it would be much cheaper for them to burn oil
rather than occasionally send people to remote locations to service engines.
This may be true but they should not pretend this is environmentally friendly.
It isn't.

If you are older you may remember how gross and foul smelling two stroke lawn
mowers used to be back in the times. We don't need to bring this back.

~~~
mannykannot
I was also wondering about this claimed lack of oil from a different
perspective.

Based on the article, the video embedded within it, and the Technology section
of Aquarius' website, this is a double-acting uniflow two-stroke internal
combustion engine. As it is double-acting, there is combustion on both sides
of the piston, so I am wondering how the piston is cooled, especially given
the high power density of this device.

In conventional IC piston engines, the piston is either cooled by the oil [1],
or, in the case of small two strokes having a total-loss lubrication system
(the sort that the parent post is concerned with) piston cooling is aided by
the flow of the incoming mixture through the crankcase. Neither method seems
to be feasible here. Has there been a breakthrough in materials (ceramics,
perhaps?) which allow for a piston to work at high temperatures?

One other point that just occurred to me is that if you are using a total-
loss, combustible lubricant design (which is what conventional gasoline two-
strokes do), then the efficiency calculation must include the energy input of
the lubricant as well as the gasoline (or whatever is being used purely as a
fuel), as the lubricant is also a fuel.

[1] [https://dieselnet.com/tech/combustion_piston-
cool.php](https://dieselnet.com/tech/combustion_piston-cool.php)

~~~
pengaru
In the video [0] it doesn't show combustion occurring on both sides of the
pistons.

[0]
[http://www.youtube.com/watch?v=26PjRQmIoeE](http://www.youtube.com/watch?v=26PjRQmIoeE)

~~~
hristov
This looks like video jacking. The description talks about acquarius, but the
video is about a completely different free piston system being developed by a
research group at newcastle university.

------
gliese1337
I am not particularly impressed with the prospects for vehicle range
extension. All-electric seems like The Way To Go at this point. But improved
efficiencies for a home backup generator seem like a potentially really great
thing.

~~~
aciswhat
Yeah generators are really the "killer app" for this

~~~
082349872349872
related work: [https://en.wikipedia.org/wiki/Free-
piston_linear_generator](https://en.wikipedia.org/wiki/Free-
piston_linear_generator)

------
rmason
Chuckled when I read they had a difficult time trying to talk with car
companies. In Detroit 2020 isn't different than 1950 in one aspect: not big
believers if not-invented-here. However if they can steal the idea like
intermittent windshield wipers they'll adapt the idea, but not quickly.

~~~
gamblor956
"Not invented here" isn't a big issue with automakers, unless you're talking
about Tesla. Most automakers license core technology (i.e., engine, chassis
designs, etc.) from other companies. Many of them license technology _from
their competitors_ or even co-develop their tech. The primary driver is cost.
They couldn't care less who developed the tech if it saves them enough money
(or brings in more money, if it's a saleable feature).

Tesla is the only company that insists on reinventing everything from scratch,
even at the cost of grossly overpaying.

~~~
cameronbrown
That's cause Telsa has the culture of Elon, similar to SpaceX. All their
success derives from rethinking traditional automakers.

~~~
evgen
You are only supposed to drink the kool-aid, not marinate in it.

~~~
cameronbrown
You could also argue that they're getting better at building things from
scratch by practicing with the mundane stuff. It's not a complete waste.

------
LockAndLol
I know it's great that engine efficiency is getting better, but this is still
working using old, crude principles. Combustion engines are the equivalent of
analog in computing and engine makers still need to reach their digital
"Eureka!" moment.

The gas turbine is [226 years old][0]! Computing on the other hand has seen
significant change from [Charle Babbabe's mechanical computer][1], to vacuum
tubes, transistors and (hopefully within the next 50 years) quantum computers.

Hopefully with progress in batteries and clean energy generation, we'll see
the death of the great polluters before the end of the century. We can (and
should) do better.

[0]:
[https://en.wikipedia.org/wiki/Internal_combustion_engine#His...](https://en.wikipedia.org/wiki/Internal_combustion_engine#History)

[1]:
[https://en.wikipedia.org/wiki/Computer#First_computing_devic...](https://en.wikipedia.org/wiki/Computer#First_computing_device)

------
TYPE_FASTER
Also check out Koenigsegg's Tiny Friendly Giant (TFG) 2l three cylinder twin
turbo that makes 600hp and 443lbft of torque:
[https://www.koenigsegg.com/gemera/tiny-friendly-giant-
engine...](https://www.koenigsegg.com/gemera/tiny-friendly-giant-engine/)

It is really cool to see these advancements happening in engine design.

~~~
ReactiveJelly
I assumed most of the trick was that the car costs a million dollars or so.

"The total output (of the hybrid system) is a combined 1700 bhp or 1.27 MW of
power and 3500 Nm of torque."

Is that torque at the wheel? If it's at the engine, who cares? It won't show
up after the gears.

~~~
gregimba
That design uses a single gear instead a traditional transmission.

[https://www.koenigsegg.com/gemera/tiny-friendly-giant-
engine...](https://www.koenigsegg.com/gemera/tiny-friendly-giant-engine/)

------
laurencerowe
I wonder how clean burning this engine is. Normal 2-stroke engines burn oil
along with gasoline so emit many more particulates than 4-stroke engines, but
this seems to require less oil than a 4-stroke.

------
beambot
34% efficiency on their first tests? That would be a _huge_ deal.
Microturbines have similar benefits (few moving parts, long lifetime, etc),
but they only realize 30% efficiency on the high end.

~~~
userbinator
34% is not that impressive...

[https://en.wikipedia.org/wiki/Brake-
specific_fuel_consumptio...](https://en.wikipedia.org/wiki/Brake-
specific_fuel_consumption#Examples_of_values_of_BSFC_for_shaft_engines)

Gas turbines and 2-stroke diesels can have over 50% efficiency.

------
DarmokJalad1701
Could this be useful for medium to long-range aviation as an intermediate step
before battery densities become more viable?

~~~
KuiN
Medium to long range aviation doesn't use ICEs, so no probably not. Aviation
gas turbines have had efficiencies >50% for a decade already anyway.

------
miahi
It seems to generate quite a bit of vibration, even if you couple two of them
in an alternating way you just change the vibration from parallel to the
pistons to perpendicular to the pistons. It's not as easy to balance as a
rotary engine.

~~~
jeffreyrogers
It's not for vehicles though. It's for power generation. I guess you could use
it in a vehicle, but I think it's intended for stationary use.

------
dang
Anybody care to suggest an accurate and neutral title, so we can replace the
baity one?

------
DennisP
Archive for those with ad blockers:
[http://archive.is/R7VlA](http://archive.is/R7VlA)

------
PEJOE
Does anyone have any thoughts on how you extract the mechanical energy from a
two sided piston?

~~~
nanomonkey
In this configuration you aren't extracting the mechanical energy, instead
it's being converted into alternating current through a linear solenoid coil.
The energy leaves as electricity.

~~~
PEJOE
Thank you!

------
aciswhat
Hopefully they'll make it into automobiles some day.

------
NiceWayToDoIT
If this was invented 20 years ago, it would be ok, but now with Tesla
basically taking over the market not just with cars, but solar, insurance,
SpaceX, communication, network of electric charging station, batteries ...
Tesla is taking over not just one market but the entire market (pumps, wells,
communication, transport, all...) Tesla is currently putting fear in bones of
other car manufacturing companies, I think now they are on high alert/panic
mode. We will see how all this pan out.

~~~
LunaSea
That's what Tesla is known for but not the brands people know for these
things.

Most people haven't heard of Tesla for solar panels. In Europe most people
don't know Tesla at all.

~~~
NiceWayToDoIT
I cannot agree about last Europe statement if we talk about 28 EU countries
they are quite aware of Tesla. In Germany there is new Gigafactory and Norway
has a massive explosion of Tesla cars on the roads. If you check the map
[https://www.tesla.com/nl_BE/supercharger?redirect=no](https://www.tesla.com/nl_BE/supercharger?redirect=no)
you will see that network is already covering, entire Western Europe...

~~~
qayxc
Norway is special.

Norway has no domestic car industry (not even major component suppliers) and
about 100% (yes, you read that right) taxes on cars.

Electric cars are exempt from tax in Norway, so it doesn't matter if you buy a
$20,000 ICE or a $40,000 Tesla. In addition you don't have to pay toll, annual
road tax, public parking fees,and may use bus lanes.

So with all these incentives in place, it's no wonder Teslas sell like hot
cakes in Norway (other EVs like Nissan Leaf and VW eGolf, too, by the way).

Every other market than BEV is practically non-existent for Tesla in Europe.
Even in the BEV market, Tesla is ranked 3rd (with the exception of Norway) in
terms of market share - behind European and Asian brands.

So unknown - no, dominating? Hell no!

