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LaunchPoint receives $500K NSF grant to further development of magnetic valve actuator

29 April 2011

Launchpoint2
LaunchPoint’s Magnetic Valve Actuator. Click to enlarge.

LaunchPoint Technologies Inc. has been awarded a $500,000 National Science Foundation (NSF) Phase II Small Business Innovation Research (SBIR) Grant (No. IIP-1058556) to continue the development of a novel magnetic valve actuator. Once fully developed, the actuator will enable the implementation of electronically-controlled variable valve timing in camless internal combustion engines.

The advantages of magnetic valve system (MVS) technology originate from the nature of the magnetic spring actuator that provides efficient control of the valve position and speed during valve opening and closing events. The Launchpoint valve actuator is based on the patented magnetic spring technology (US Patent# 7,265,470) originally developed by LaunchPoint for an aerospace application.

Launchpoint1
Several superimposed switching curves collected during the Phase I experiments with the valve actuator traversing an 8 millimeter trajectory in 3 milliseconds. The data reveal consistent switching trajectories and very smooth landings with speeds less than 0.3 m/sec and almost no oscillations. Source: LaunchPoint. Click to enlarge.

A bench-top prototype developed during the Phase I effort demonstrated outstanding performance characteristics. Test results showed that the actuator was able to traverse an 8mm stroke distance in 3 milliseconds with consistent switching trajectories and very soft landings.

The Phase II development effort, led by Principal Investigator Mike Ricci, VP of Engineering, will be aimed at reducing the switching interval even further while improving robustness of the design. During this phase LaunchPoint engineers will design, construct, and test on an experimental engine, a second generation of the magnetic valve actuator integrated into a complete engine subsystem. This Magnetic Valve System (MVS) will comprise the magnetic valve actuator, an integrated sensor, a control unit, and a power amplifier, which together provide electronic control of the valve timing.

Variable valve timing is the Holy Grail of internal combustion control. The advantages of our technology stem from the inherent nature of the nonlinear magnetic spring used as the primary valve actuator. The nonlinear spring provides most of the energy required to open or close the valve while also ensuring a soft landing. The low-power electromagnetic actuator is used only to “throw” or “catch” the valve at the beginning or the end of the stroke.

—Dr. Maksim Subbotin, Systems Engineer and Principal Investigator for Phase I

Magnetic valve actuators can be applied to a wide variety of internal combustion engines. Actuators of this type would eliminate the numerous engine components required for a typical camshaft drive, thereby decreasing manufacturing and maintenance costs and increasing reliability.

Magnetic actuators could be designed into new engines as well as retrofitted to existing engines. They could enable implementation of emerging advanced combustion technologies such as Homogeneous Charge Compression Ignition and Compressed Air Hybrids. The widespread adoption of these actuators would substantially decrease petroleum usage and the associated production of greenhouse gases and air pollution, the company suggests.

LaunchPoint Technologies Inc. is an engineering services and contract R&D firm with expertise in electromagnetics; control theory; motor and generator design and development; medical device design and development; CFD optimization, and prototyping. LaunchPoint works with government agencies, companies, and entrepreneurs to develop new technologies, secure IP, and procure funds for commercialization efforts.

April 29, 2011 in Engines, Vehicle Systems | Permalink | Comments (29) | TrackBack (0)

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Comments

Electronically controlled magnetic valves, opposed cylinders, electronically controlled laser plugs, electric two stage compressors etc etc could produce better ICE with less pollution and less fuel consumption. Will industry have time to incorporate those changes before electrified vehicles take over?

The end of the internal combustion engine is a ways off yet.

You would have enough control on the valves to make the engine able to run atkinson or otto depending on load

It would be interesting to know 1. What kind of voltage is required to make this work, and 2. Is the energy required to run this type of valve train more or less than a camshaft. After all, upon valve closing in a mechanical valve train, the expanding spring returns energy to the rotating camshaft. I don't see that energy conservation happening here, unless I'm missing something.

Harvey

Yes they will have time , because EV won't take over any time soon

The power and voltage requirements more or less necessitate a hybrid drivetrain. BMW tried electric actuators a couple of years ago but apparently dropped them in favor of the fully-variable mechanic valve train (Valvetronic).

Mechanical valve trains are much more efficient than electric valve trains. With roller bearings (in addition to roller followers) the mechanical valve trains will be even more efficient. Thus, electric valve trains will have difficulties to compete. Furthermore, mechanical valve trains can already provide variable valve actuation (e.g. BMW and others). Hydraulic (and possibly pneumatic) valve trains are other options. Some of the energy could be recuperated with these systems. For example, the Fiat hydraulic valve train seems as a very neat system. However, this system still uses a camshaft. I can see a niche for electric valve trains in free-piston engines where you do not have a rotating shaft readily available for driving a mechanical valve train.

BTW, look how enormous the actuator is. There is little room for such big components under the hood of a modern car. How can you make (without compromises) a 4-V cylinder head with these actuators?

Treehugger...hope that you are under estimating the time it takes to incorporate major changes in ICE and also the arrival of many types of electrified vehicles.

Peter_X.... this is a very first model. Future models could be many times smaller. Electrified/electronic ancillaries are moving in ICE and Electrified vehicles at a fast pace. The idea is to replace most mechanical/hydraulic parts/components to lower weight, reduce maintenance, reduce fuel consumption, reduce GHG and extend life.

I could see an electrically triggered air system. 10,000 psi should get some snappy performance, you have to keep the valve mass low, but they have been doing that for a long time.

Having continuous control over the valve timing can bring many benefits and there are several ways to do that. I would say that pure electric solenoid actuation would take lot of power and a huge solenoid to move an engine valve the required distance in a few milliseconds.

After examining their patent, they seem to be advocating replacing the spring with a solenoid. They still show a cam pushing on the valve stem, but electro magnets return the valve and keep contact with the cam follower.

HarveyD
This model is bigger that the first prototype I heard about some 20 years ago. Some progress...

Electric ancillaries? Regulated mechanically driven oil and water pumps are more efficient than electric ones. Engine makers have just recently discovered this fact...

SJC
Yes, pneumatic actuation could be an option. There is a Swedish company (www.cargine.com) who develops a pneumatic valve train. Pneumatic valve springs have been used in Formula 1 engines for many years but that is not quite the same topic...

I am surprised they have not retained a spring, mechanical or pneumatic. That way the electro actuator could act like generator-motor, and recover much of the energy in the return stroke.

Maybe they are planning that, but just leaving it out for simplicity of demonstration.

An electro mechanical magnetic damper night not be a bad idea. Springs bounce depending on frequency and hydraulic lifters are clumsy at speed, so just do it with electro magnets that can be an actuator and encoder.

@ Nick Lyons

Some of the electrical energy stored in the solenoid should be recoverable when its magnetic field collapses.

I can't comment whether the mechanical energy stored in the spring is recoverable since this report gives insufficient design detail to make an accurate assessment.

@ Nick Lyons

The patent claims might be a good place to seek an answer to mechanical energy recovery.

@Harvey

I myself would love to see the transition to electric vehicles however considering the orders of magnitude in energy density improvement batteries need before they can replace gasoline, combined with the rate at which the vehicle fleet replaces itself, I have to agree with SJC that the ICE is going to be here for many years to come, especially in heavy duty applications.

@3peacesweet

I thought the exact same thing, combining this technology with direct injection would allow for engines that are efficient at nearly all load and speed conditions. The top efficiency islands could be expanded to cover the majority of the engine map. This would have the side effect of reducing the advantage hybrids have over traditional drivetrains. Controlling valve lift and dwell timing could allow you to greatly increase the expansion ratio at part load and act like an atkinson cycle engine. At full load you could also get more HP, a disadvantage in Atkinson engines. You could also reduce throttle pumping losses as in the system Fiat uses

@Peter XX
Agreed this actuator is much too large to be viable in many engines, however you consider that the whole valvetrain would be replaced with several of these the increased size isn't much more.

Also you have to consider that the model in the picture is based off of an experimental benchtop model in the earliest stages of prototyping. I have a strong feeling that a production model could be made much smaller.

As for the competition, Fiat pulled off this feat on their multi-air engines, at least on the intake side, however as you said it still requires a camshaft.

@GDB

"Test results showed that the actuator was able to traverse an 8mm stroke distance in 3 milliseconds with consistent switching trajectories and very soft landings."

I bet they probably went without springs to reduce the inertia of the moving parts, decreasing the amount of energy required to actuate the valve. Lower inertia also means you can rev to higher RPMs as long as the actuator can keep up.

I would also imagine that if you were to have very high rate springs capable of closing very quickly the power requirements to overcome the spring force would be much higher than without a spring. Removing the spring also allows for the "soft landings" described in the article, possibly allowing for even lighter valves with even lower inertia

George
There is not room enough for 4 valves in a cylinder head with an actuator as large as this. Anyone can see that. So, in essence, you would have to design a 2-valve engine to fit the actuator. A 2-valve engine is generally less efficient than a 4-valve engine and has lower power density, so you would need a bigger engine to do the same job. Furthermore, a 2-valve engine needs a higher valve lift (since the valves are bigger) than a 4-valve engine. Thus, an even bigger actuator would be necessary. As I said in a previous comment, I saw smaller prototypes than this one already some 20 years ago. I am not impressed. Maybe development in this field is even slower than for BEV batteries.

BMW already has a functional fully-variable mechanical valve train. It has roller components in the valve train and thus, low friction (however no roller bearings for the camshaft). It is a 4-valve engine. So, the potential for reducing fuel consumption is already known and well-documented (for example, look in the German journal MTZ for a couple of articles during the last years). The biggest benefit is in reducing throttling losses.

I think you might not fully understand how an Atkinson cycle works. You cannot both have high expansion ratio and high power at the same time. The compromise that Toyota has made is that they increase expansion ratio and reduce power. You cannot both have the cake and eat it.

Electrified vehicles using electrified ancillaries will simplify future personal transport units. The current e-storage challenge will be solved. Weight and cost per Kwh will come down by steps on a regular basis. Post lithium batteries may be around by 2020. Competitive long range BEVs with 300+ miles between quick recharge will be around soon thereafter.

Heavy long range vehicles will use the PHEV solution with an on-board genset or FC.

Short range heavy vehicles such as city buses and city cabs (both successfully tried in China) will definitely be quick charge BEVs.

Peter,

Some good points, however I still would think that once this design gets to stage II or even stage III prototyping the size could be significantly reduced. I can't predict what going to happen though so we will have to wait and see where this technology goes.

As for my point on Atkinson cycle operation I still do not see why with a completely variable system you couldnt induce atkinson operation during part load conditions and switch back to regular otto cycle when the driver demands more power.

From examining the engine used in the Prius, the only major difference is that the intake valve is held open for an extended period during the compression cycle, making the compression ratio smaller than the expansion ratio for increased efficiency.

What I dont understand is why you couldn't program the valve-train to go back to normal otto cycle operation when more power is demanded, effectively increasing the power density over atkinson cycle and giving you the best of both worlds.

Harvey,

I know our best engineers will solve the energy density issue with batteries beyond lithium ion because the theoretical densities I have seen are just astounding.

The problem I see with quick charging the very large batteries that are smaller than todays is charging efficiency and grid capacity. Lets say you have a battery with two times the capacity and one half the size of todays battery and you charge it in the same time as a battery from today.

You're effectively putting four times the amount of energy in the same volume. Amplify this effect because people want their batteries charged very quickly and I could see the batteries getting very hot. How do you charge these compact batteries quickly without destroying them or requiring a massive cooling system?

Lastly charging rate at your home is limited by the 240V hookup that most homes have. You can only put so much current through the wires before you trip a breaker somewhere in the system. Wouldnt very high charging rates require rewiring entire neighborhoods to handle at least 480V service?

George
I will just give a short explanation this time but I hope you understand… The Atkinson cycle use a very high compression/expansion ratio (e.g. 14:1). You have to have a late – or an early – inlet valve closure to restrict the effective compression ratio to avoid engine knock. If you reduce the effective compression stroke by, say 30% via (early or late) valve timing; you also reduce power by ~30%. If you try to operate with an inlet valve closure at an “optimum” timing for volumetric efficiency, your engine would more or less “explode” due to the high compression ratio, i.e. severe knocking would occur. You cannot have the cake and eat it. You must choose between efficiency and power. I hope I have now also provided an explanation for the poor power density of the Toyota engine.

Peter,

Definitely makes more sense now, didnt know the expansion ratio was so high on atkinson cycle engines. If only there was some way the to reduce the knocking effect then you could have a completely customizable engine i.e. you could control pretty much every variable.

Would it be possible to design an engine using more conventional expansion ratios and "throttle" it by keeping the intake valve open longer at lower loads, thereby reducing throttling losses? That way it would be a normal engine at full load but would benefit by expanding the gases more when not using full throttle. Maybe I'm being redundant here, is this how that BMW works to reduce throttling losses?

An analogy is that it would be similar to direct injection, use stoichiometric mode at high loads (for optimized power) and use stratified charge combustion for low loads(optimized fuel efficiency). Wouldn't this technology be especially good for highway cruising? (low fairly steady loads)

Solenoid motion can be damped by shorting or even applying braking current, converting mechanical energy into current in the solenoid. This current can then be dumped back into the supply bus after motion stops, converting the magnetic flux back to electric power.

Toyota could both have and eat their cake if they turbocharged their engine. Supplying air at e.g. 2 bar would also allow the unit to be downsized considerably and made even more efficient.

Do these actuators have a future? No idea, but they can't hurt.

George
Yes, this is BMWs concept, except that they close the inlet valve early instead. Both late and early closure is possible. There has been a debate about which option is the best so this probably answers that question.

A couple of years ago, BMW dropped the Valvetronic for stratified combustion (albeit not on all markets). They gained a couple of per cent in fuel consumption due to lower pumping losses. Although Valvetronic has fast actuation and low throttling losses, an open throttle is even better. Another advantage with a conventional valve train was higher engine speed and thus, higher power (+20 hp). However, the newest (6- and 4-cyl) engines have again Valvetronic but in combination with stoichiometric combustion and turbocharging. With turbocharging, engine speed has to be reduced, so this disadvantage of Valvetronic in that respect is no longer present. The advantage of downsizing is similar for both stratified and stoichiometric combustion. One disadvantage with stratified combustion is the lean-NOx catalyst that has to be used to control emissions. The new turbocharged 4-cylinder engine will replace the naturally aspirated 6-cylinder engines. I suppose the current naturally aspirated 2-liter 4-cylinder engine will be replaced by a smaller turbocharged engine shortly.

I was hesitating to put in an explanation of the Miller system in my last comment but I did not want to confuse with too much information, so it was not included. While it is obvious that you cannot both have and eat the cake, you can have a sandwich instead of the cake. The Miller system is a “sandwich” and, with recent information provided, Toyota might introduce that in the future. The Miller system use an Atkinson cycle with turbocharging. The power lost by early inlet valve closure is re-gained by turbocharging. However, you still cannot achieve the same power level as a conventional turbocharged engine. The sandwich cannot fully replace the cake. Current single-stage turbochargers cannot achieve the desired charge pressure over the whole speed range. Two-stage turbocharging (with two cakes, you can eat one) or combination with supercharger and other options might eventually solve this problem. So, now you also know why BMW is not using an Atkinson cycle and Miller system; the put higher priority on power than on fuel consumption. BMW could easily increase the geometric compression ratio and re-calibrate valve timing to achieve this. However, it might be difficult to sell a BMW car with the “poor performance” this engine would provide.

Sometimes engineering has solutions in search of problems. When you figure cost and price, superchargers and turbo chargers become expensive and complex. They do the job and increase the price of the car. It is the elegant and simple solutions we seek.

George....high battery charging rate is a challenge that will have to be solved, specially for (100+ Kwh?) light weight batteries installed on future long range (700+ Km) BEVs.

There are three different possible solutions:

1. Very high capacity batteries (100+ Kwh for up to 700 Km) that would be slow charged overnight while the user sleeps.

2. Very quick charge smaller (40 Kwh to 50 Kwh) batteries that would have to be recharged quickly every 300 Km or so while the driver is having a coffee.

3. A compromise solution for shorter range (100 Km to 150 Km) city cars with a smaller (20 Kwh to 30 Kwh) slow or quick charge battery that would normally be slow charged at home or at the working place.

Charging rate for solution 1) and 3) could be limited to reduce heat generation to acceptable level.

Appropriate heat dissipation or recovery would be required for solution 2). DC to DC quick charge could help.

We have already exploited the simple and elegant solutions. Cost is the reason why someone still has not built the “ultimate solution” for a gasoline engine comprising (among other things...):

• Atkinson/Miller
• Fully-variable valve train (mechanical, pneumatic, hydraulic or electric)
• Two-stage turbocharging with variable compressor/turbine geometry, ceramics, roller bearings, inter- and aftercooling and any other feature you could imagine
• High pressure (>500 bar) direct injection
• Extreme downsizing (including fewer cylinders)
• Downspeeding
• Low friction
• Waste heat recovery

I might add that the concept above could be amended or varied and might be combined with hybridization. It is not going to be cheap...

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