Session C8
Paper #50
Disclaimer—This paper partially fulfills a writing requirement for first year (freshman) engineering students at the University
of Pittsburgh Swanson School of Engineering. This paper is a student, not a professional, paper. This paper is based on publicly
available information and may not provide complete analyses of all relevant data. If this paper is used for any purpose other
than these authors’ partial fulfillment of a writing requirement for first year (freshman) engineering students at the University
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THE FUTURE OF INTERNAL COMBUSTION: CAMLESS ENGINES
Anthony Barca, [email protected], Budny 10:00, Scott Moskal, [email protected], Budny 10:00
Abstract—For years, the internal combustion engine has
dominated the transportation industry. Today, many of the
components of the internal combustion engine - from fuel
injectors to turbochargers - have improved tremendously since
their creation. Despite this, one of the most important
components of the engine, the valvetrain, is yet to be totally
reinvented. As greenhouse gases continue to create more
issues for our environment, many automotive engineers are
trying to develop new ways of achieving higher efficiency from
their engines. The most promising new piece of technology is
the camless engine, an innovation that will change the way the
engine operates. Camless engines employ a computer aided
system that controls each individual valve in the cylinder of an
internal combustion engine via a mechanical device such as a
pneumatic or electromagnetic actuator. This can result in the
best optimization currently available in engine efficiency,
possibly leading to a downward trend in emissions if widely
implemented. Such a downward trend could also pay dividends
towards the sustainability and protection of the earth’s
resources and the health of all citizens. However, before
proper implementation can occur, much more research,
design, and testing must be performed to make the system
practical for real world application.
Key Words—Camless engine, Electromagnetic actuators,
Engine emissions, Internal combustion engine, Pneumatic
actuators, Valvetrain, Variable valve timing.
have increased power outputs and emission ratings, but they
cannot afford to stop there. Innovations must keep surfacing
in the automotive world, and engineers are developing a
technology that has the potential to take the refinement of the
ICE to a whole new level.
The technology that can change the future of the ICE
technology (and the future of the environment) is known as the
camless engine. The camless engine is a special kind of ICE
that does not need camshafts over each bank of cylinders to
actuate the valves for each cylinder. Instead, it uses a system
of mechanically operated valves programmed to activate at a
specific frequency and depth into the cylinder. This new
technology will provide potential gains to the automotive
world.
Alternative sources of power for automobiles usually
come in the form of electric, hydrogen, or even air-powered
vehicles. While these new technologies are currently being
designed and implemented without the use of fossil fuels, they
are still in development and will take many years until they are
as reliable, practical, and affordable as their internal
combustion counterparts. Until then, the use of fossil fuels is
required for most automobiles, and must be optimized using
the latest technologies to ensure that our society is using as
little of these resources as possible.
THE INTERNAL COMBUSTION ENGINE
Components
INTERNAL COMBUSTION TODAY
Every day, greenhouse gases such as the carbon dioxide
emissions that result from the combustion of fuels in internal
combustion engines (ICE) are accountable for a large portion
of the pollutants in our environment. The main effects of
increased greenhouse gases are global warming and adverse
health problems. With emissions at their highest levels in the
last decade and an increasing number of vehicles on the road,
global warming requires special attention.
Since the creation of the ICE, engineers have been
researching new ideas to produce more power and less emitted
pollutants with the same amount of fuel. Efforts include the
use of multiple valves, electronic fuel injection, and variable
valve timing. The effects of these developments on the ICE
University of Pittsburgh Swanson School of Engineering 1
31.03.2017
There are a few main components of an ICE that must be
introduced to explain its function. A visual representation of
the internal combustion engine can be viewed in Figure 1.
Starting at the top of the diagram, the intake manifold (referred
to as the intake), pulls in air from the atmosphere, filters it, and
channels it to the cylinders. Next, the valvetrain controls the
valves of the cylinders, opening and closing them to allow the
air to flow into the cylinder, and allowing exhaust gases to exit
out of the exhaust system. The fuel injector, located in the
cylinder, sprays a fine mist of fuel in with the incoming air to
prime the mixture for combustion. Spark plugs then create an
arc of electricity to ignite the mixture, which causes the gases
to expand in the cylinder. The force from these expanding
gases then pushes a piston down in the cylinder, connecting to
Anthony Barca
Scott Moskal
the crankshaft to turn the force into rotational motion. From
there, the power is sent through the flywheel, transmission and
axles, until it reaches the wheels.
possess a valvetrain that is responsible for the opening and
closing of the intake and exhaust valves [2]. They accomplish
this task by using fixed lobes on a spinning shaft known as the
camshaft, which actuates the valves and pushes them into the
cylinder to let air and fuel in and exhaust gases out.
For years, engineers in the automotive industry have been
finding ways of perfecting this system, modifying the location
of the camshaft and valves in the engine, and turning to modern
electronics to create systems that can adapt to changing engine
speeds. In more recent history, engineers have created a
system using variable valve timing (VVT), which combines
the best arrangement of the valvetrain and advanced
electronics to get the best performance from an ICE. What
makes VVT technology the best out of any current techniques
is its use of cam phasors that electronically or hydraulically
change the cam that each valve is using, effectively increasing
the airflow at the necessary speeds [3].
Due to the focus on the valvetrain and its best possible
configuration, automotive companies are going beyond these
simple cam phasors to create a system that can better adjust to
an ICEs changing speeds and conditions. This is where the
idea of a camless system comes into play. From extensive
testing, automotive engineers have discovered that camshafts
are limited in their customization, so the next step in realm of
the valvetrain is to completely remove the camshaft altogether
and replace it with a fully customizable system [4].
FIGURE 1 [1]
Internal Combustion Engine Diagram
Combustion
ROOM FOR IMPROVEMENT
Behind every ICE in an automobile, there is the same
basic principle: to convert as much potential energy stored in
fuel into mechanical energy that can be used to propel the
vehicle. This is achieved through the combustion process, in
which air from the atmosphere is drawn into the engine, mixed
with a vapor of fuel, and ignited with enough force to drive the
piston down in the cylinder. This is also the first place that
engineers look for improvements, altering the amount of fuel
that the fuel injector sprays each time and how much air is let
into the engine, creating the best air to fuel ratio. An air to fuel
ratio can be created to fit the needs of any specific engine,
whether it is a high-performance engine with a high ratio or an
economically focused engine with a lower ratio.
Engineers also fine tune this process by increasing the
efficiency in converting chemical energy to mechanical energy
by using techniques that reduce the temperature of the
incoming air. Reducing the temperature of the gases in the
cylinder will allow more oxygen to be mixed in with the fuel,
creating a more powerful reaction without burning any excess
fuel. This is one way that emissions can be reduced in
automobiles. The most critical component for optimizing the
ICE and its combustion process, however, is the valvetrain.
Greenhouse Gas Emissions
One of the most significant challenges facing us today is
the protection of the environment from pollution. Having
grown so rapidly in the last century, the human population has
caused the number of vehicles on the road to continuously
increase at a high rate. In Jerry Hirsch’s 2014 Los Angeles
Times’ article on increasing vehicle usage, he reports that we
have “reached a record level of 253 million, an increase of
more than 3.7 million” in one year [5]. Vehicle usage also
continues to soar due to the economy and the increasing quality
of automobiles. These automobiles are one of the major causes
of global warming, accounting for a large portion of all
emissions in the United States, affecting health, security, and
many other human needs.
With the rise in the number of vehicles on the road,
increasing levels of pollution continue to harm our
environment and the protection of the earth’s resources. Other
sources of power, such as electricity or hydrogen, need more
time to become truly practical. This means that ICEs will
remain dominant for many years to come. Therefore, it is
necessary to understand this problem and learn ways to
minimize pollution. Focusing on transportation, the main
greenhouse gas emitted is carbon dioxide, which results from
the combustion of gasoline in an ICE. According to the United
States Environmental Protection Agency (EPA) in “The
Sources of Greenhouse Gas Emissions,” about a fourth of all
Valvetrain
The valvetrain controls several key components that
directly affect its performance, and is the area that can
potentially see the most improvement. Presently, most ICEs
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greenhouse gas emissions come from transportation. The EPA
also reports that greenhouse gas emissions have continued to
rise over the last several years due to an “increased demand for
travel and the limited gains in fuel efficiency” [6]. These
emissions in the United States have continued to increase since
the 1990s. Many people also tend to be on the road more often,
as well as traveling further to a destination than in the past [6].
The growing number of people on the road is largely due to the
rising population growth, economic growth and low gas prices
at the beginning of the twenty-first century.
With all these parts in the ICE moving faster, the air and fuel
mixture also follows this pattern, causing turbulence in the
cylinder. If the valves do not adapt to open widely enough, the
necessary amount of air and fuel will not occupy the cylinder,
drastically reducing top-end performance and efficiency. This
is where the idea of a camless valvetrain could improve the
process of combustion that engineers have been developing for
years, to ultimately reduce the impact of ICEs on the
environment.
THE CAMLESS VALVETRAIN
This revolutionary new type of valvetrain and its
promising test data show that it has the potential to be the
future of internal combustion. However, as with any new
technology, there also arises many new challenges that
automotive engineers must overcome to make the camless
system reliable and cost-effective enough to replace the current
version of the ICE. The design and implementation of the
camless engine is crucial to providing better efficiency and
protection of the environment.
Basic Components
While the technology behind the function of the camless
engine is quite complicated, its theory is simple: remove the
camshafts and replace them with a fully customizable system
that controls each valve individually. This will reduce
emissions and fuel consumption without the loss of power and
reduce its influence on the environment. To create a camless
engine, three main components must work together in an
efficient and flawless way.
The first and most important element of a camless engine
is the valve actuator. One actuator must sit above each set of
intake and exhaust valves, so that they can be controlled
independently from the others. It must use one of several
possible techniques for physically pushing the valve down in
the cylinder in a controlled manner, using either an
electromechanical system or a hydraulic system [2].
Another component of the camless engine is the way in
which the engine generates enough electrical energy to run the
valve actuators. In order for the engine to be more efficient, it
must not lose too much energy in operating the electronics that
control its components [3]. A low friction generator and very
advanced electronics must be employed to create the large
amount of power required to run all its actuators
simultaneously.
The third main component of a camless valvetrain is the
control system required to tell the actuators when to operate
and how far to push the valve down in the engine, according to
engine speed. This will require lots of programming by
engineers and computer scientists to fully optimize the system.
These three main components of the valvetrain are the basis
for a camless engine, which becomes much more complicated
when designing them to function efficiently.
FIGURE 2 [6]
Greenhouse Gas Emissions from Transportation
Figure 2 depicts a graph of the greenhouse gases emitted
from transportation alone in the United States, showing that
the greenhouse gas emissions continue to increase each year.
During the Great Recession in 2007, the carbon dioxide
emissions fell at a high rate because of the cutbacks in
consumer spending everywhere, along with a lower number of
drivers on the road. However, once the Recession ended,
carbon dioxide emissions continued to increase over the next
few years.
The Limits of the Camshaft
To decrease the greenhouse gases emitted from the
transportation industry, the camshaft of the ICE will need
modification. This part of the ICE has been around since its
creation, being one of the most critical components of the
engine by opening and closing the valves.
For the combustion process to occur as efficiently as
possible, the intake and exhaust valves must open at the right
time. According to Francois Badin’s book Hybrid Vehicles
From Components to System, “the height and duration of valve
lift is fixed, being determined by the profile of the cam” [3].
These camshafts are unable to properly adjust to the increasing
speeds of the engine. Just like the speedometer measures the
speed of a car, the tachometer measures the revolutions per
minute (RPM) of the crankshaft. Increasing the RPM causes
the valves to open and close even faster along with the pistons.
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In fact, the standard automobile currently operates on a 12V
system, which would not be able to run all the components in
a camless engine. Rather, the automobile needs at least a 42V
system to operate all components tied into the battery [2]. In
creating all the necessary power to run the system using more
powerful electronics, it is important that the efficiency of the
engine is not affected by the added strain of more rotating
components from extra generators and alternators [3].
The Valve Actuator
To physically move the valves individually at high
speeds with pinpoint precision is the job of the valve actuator.
Many engineers have implemented existing technologies to
actuate the valves in camless engines, starting with
electromechanical actuators. These devices use a “spring
system” to hold the valve in its middle position, and two coils
that are “energized alternately to attract an armature,” as seen
in Figure 3 [2]. Due to the powerful electromagnetic force
between the coils and armature, the valve can be operated at
high speeds, and at various depths. In camless engine
development thus far, the electromechanical system has been
the best for speed and control, but there are alternate methods
being developed that can also control valve depth.
Providing Full Control
As promised by the development of a camless valvetrain,
the valves must operate independently of each other, creating
the need for a dynamic control system. Similarly, all new ICEs
have computerized control of various components such as
timing for the fuel injectors, spark plugs, and their VVT
mechanisms. The same is true for a camless engine, which
needs software similar to what is used now, except with much
more complex programs to time the actuators rather than a
VVT system. Extensive research must be done to determine
the optimal depth and speed of a valve at any engine speed,
which is to be programmed into the system. Another aspect to
consider is the need of the software to regulate how much
energy is going to each actuator so that no component is short
on power. Once a well-developed and customizable software
is created that can handle the high demands of control required
by the system, the final tuning and optimization stages can
begin.
Techniques of Optimization
The principals of combustion discussed earlier apply to
every ICE, and the camless engine is no exception with regards
to performance and efficiency. With several factors to
balance, such as fuel economy, emissions, or power, finetuning an ICE is a lengthy technical process to fulfill the
purpose of a specific engine. Over the years, automotive
engineers have come up with several other ways of reducing
emissions while increasing the power that the camless engine
can take even more advantage of, revolutionizing each
technique.
The first technique stems back to the idea of getting the
most power from the same amount of fuel, by controlling at
what engine speed the most power or torque is produced.
Torque in automobiles is most often referred to as the rotating
force on the crankshaft to get the vehicle moving, while the
power is the maximum rate at which the engine can perform
this torque on the crankshaft. In most cases, the engineers
specifically implement this maximum torque output at certain
engine speeds for different purposes, to get the vehicle up to
speed quicker if it has a larger mass. With the full valve
control offered by a camless engine, fixing this range of
maximum torque is much easier and allows for much finer
adjustments. Not only can these adjustments place the power
and torque peaks at more economical positions, but they are
also engineered to be more “full,” creating more power, and
Figure 3 [7]
Operation of an Electromechanical Actuator
One of these alternate methods includes the use of
hydraulic controllers, in which the valve is controlled with a
system of hydraulic fluids [2]. The fluids are pumped into the
valvetrain, and the pressure that they create is enough to move
the valves independently of one another. While this system is
one of the most effective alternatives to an electromechanical
actuator, it suffers from various drawbacks. Some of these
drawbacks include its increased complexity and mass that it
adds to the vehicle, and the fact that the viscosity of the fluids
will change with the vastly changing engine temperatures,
affecting performance and accuracy [2]. As developments in
hydraulic systems are improved, they will become more
practical for use in a camless valvetrain, but for now, the use
of electromechanical actuators is optimal for performance.
Powering the System
To operate the very complex and powerful actuators in a
camless engine, a large amount of electricity is required.
According to IFP Energies Nouvelles expert Francois Badin,
“considerable power” is required to move the valves down into
the cylinder, even though they only move a short distance [3].
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accelerating the vehicle at a higher rate so that even less fuel is
burnt in reaching the desired speed [3].
Another technique that will be more improved than ever
before is increasing efficiency at low speeds. Taking a current
example of an ICE at low engine speeds, the main flaw is that
it only has one fixed valve travel depth and frequency. This is
also the same valve travel and frequency as at much higher
engine speeds, so the valves are not opening optimally for
slow-speed situations, resulting in pumping loss. Pumping
loss is caused by the suction force that the piston must use to
pull air into the engine at low speeds, reducing the efficiency
of the engine through energy loss [7]. A shorter travel depth
and frequency can be assigned to each valve, making for much
lower mechanical resistance at slow speeds and increased
efficiency.
Although there are many other possible techniques for
optimizing the operation of a camless ICE, the final example
discussed in this paper deals with the amount of pollutants
emitted in every cycle of the engine. A fairly recent process
has been engineered so that the engine does not pull in all new
air from the atmosphere and expel the exhaust fumes produced
in each cycle. This process is known as Exhaust Gas
Recirculation (EGR), which effectively reduces the amount of
exhaust gases and pollutants that leave the engine through the
exhaust manifold [3]. Camless engines can make this process
much simpler, by “regulating the overlaps” of the intake and
exhaust valves [7]. As a byproduct of this technique, reducing
the amount of air pulled in from outside of the engine will also
result in a lower pumping loss [3].
Most of the techniques for optimization work closely
with each other to create a truly remarkable machine that can
adjust on the fly. This ability is created by advanced valve
actuators, cutting-edge electronics, well-developed software,
and the tuning of an ICE with a camless valvetrain that can
greatly decrease the carbon footprint that automobiles create.
FIGURE 4 [8]
FreeValve Actuation System
FreeValve’s technology, as shown in Figure 4, is a type
of variable valve actuation that allows the timing of the valve
to be programmed into the engine’s control system. According
to FreeValve, they use “electro-hydraulic-pneumatic actuators
combined with advanced sensor techniques” to control the
valvetrain [8]. In 2009, FreeValve installed this system in a
SAAB 9-5 to test its practicality, with very impressive results.
After 55,000 kilometers of real-world use, the system has
performed well, even down to temperatures of -20℃ [8]. Since
then, FreeValve has created six generations of actuators that
have improved dramatically over the past few years, with a
“verified fuel consumption reduction of 12-17 percent” [8].
Another concept vehicle, named the Qoros, has partnered with
FreeValve to create an engine that benefits from a 47%
increase in torque and a 45% increase in horsepower compared
to its unmodified 1.6-liter engine [8].
These numbers show some outstanding progress made
over the years, and FreeValve hopes to continue the trend of
reducing fuel consumption. Collin Woodard’s article on
R&T.com illustrates how FreeValve’s technology functions
and reduces pollution with benefits such as “better power,
torque, efficiency, fuel economy, and emissions” [9]. Also,
included in the article was a video made by Engineering
Explained, which graphically demonstrated how the
FreeValve system works, and explained some of the
challenges faced by the company. These challenges included
the cost of components in creating the FreeValve system, and
how a lot of testing is still required to perfect the system [9].
With claims in the future of creating 30% more fuel efficiency
and 50% less emissions, FreeValve is truly the frontrunner in
implementing the camless engine that could potentially cut the
automobile’s impact on the environment in half [9].
FREEVALVE
In 1994, the Swedish automotive company Koenigsegg
launched a new car company with a goal of producing worldclass sports cars. Koenigsegg’s success throughout the 1990s
led to the creation of its sister company FreeValve, which
began work on a new technology in the summer of 2000.
Without much implementation of camless engines at the time,
FreeValve was one of the first companies to include this new
technology in its design. FreeValve’s goal was to reduce the
greenhouse gas emissions and fuel consumption from the
transportation industry by improving components for the ICE.
During the early 2000s, FreeValve produced their first valve
actuation system that modeled the process of a camless engine.
SOCIETAL IMPACT
Evaluating not only the performance and potential
rewards of a technology, but its repercussions on society is also
a concern of any innovation, and the engineers behind it. A
large amount of research must also go into determining if the
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benefits of the camless engine will outweigh any
disadvantages in the real world.
In this evaluation, a definition of what it means for a
technology to encourage the sustainability of the earth is
important. According to the EPA, sustainability is “to create
and maintain the conditions under which humans and nature
can exist” to “support present and future generations” [10].
Creating such an environment, therefore, is one of the most
important things that scientists, engineers and diplomats can
do for others in the future.
Where the engineers behind camless engines will come
into play is in the impact of the ICE on the ecosystems,
resources, and overall health of the environment. As per
section 7 of IEEE’s Code of Ethics, it requires an engineer “to
accept responsibility in making decisions consistent with the
safety, health, and welfare of the public” along with disclosing
“factors that might endanger the public or the environment”
[11]. Making ethical decisions that are for the benefit of all at
the expense of none is what engineers as a whole must follow
in their professional endeavors, and is the only way to truly
accomplish this harmonious existence between citizens and
nature.
result would almost certainly counteract any increased power
consumption and resource use from the production of the
systems themselves [8]. Over time in fact, the resource
conservation for future generations will be increasing more in
the few years following the production of camless valvetrains
“than in the previous one-hundred” [8]. This will make the
investment pay off many times over, and save more fossil fuels
for future generations.
Although the current limitations of price on the
implementation of the camless engine on the market may also
make it appear impractical, it is important to remember that
innovations in a particular field take time to develop and be
properly tested so that they can be depended on. VVT systems
in modern ICEs were developed in this way. Once these
technologies are widely implemented, the costs will start to go
down, making the technology more accessible to consumers.
The more consumers that are able to purchase the technology
the better, and will contribute to a healthier environment that
will increase the sustainability of resources and ecosystems for
years to come.
WHEN WE WILL SEE MORE CAMLESS
ENGINES
Drawbacks
While the camless engine and its various components are
all still being developed to work together as effectively as
possible, not many examples will reach the market for mass
production for a few years. The reason for this delay is because
of the new and advanced electronics required to operate the
system, which makes the production of the engine too
expensive for the industry to produce in mass quantities. Also,
additional testing must be done by automotive companies to
ensure that camless engines are reliable and practical enough
for everyday use, and that they can deal with the extreme
weather conditions that they will be exposed to where they are
sold.
With the state of the environment in the spotlight
recently, it is very important to continue improving every
technology that is used so that its impact is minimal.
Eventually, camless engines can be implemented into all kinds
of transportation, such as locomotives or vessels, or in any
instance that internal combustion is used.
When considering the impact that the ICE has had on our
past, it ranks among the greatest inventions in history because
of how it changed the way people transitioned from place to
place. The quality of life has also benefitted from the ICE,
because of how much more one can accomplish in one day.
Now that automotive engineers have taken one of the most
crucial inventions in the past 200 years and reinvented it, the
potential rewards with regards to the environment and quality
of life everywhere can continue to climb. The camless engine,
in design and testing has proven to be the next step for internal
combustion, showing just how this new technology is truly an
innovation not only for automobiles, but also for the course of
history.
Engineers will take these codes of ethics and other
situations throughout history into consideration when
examining the negative aspects of this new technology.
Among the few drawbacks of the camless engine are the
current costs of production and the increased resources that are
needed to produce all the extra components for a camless
valvetrain.
High costs of production result from the fact that no
automotive company has mass-produced a camless engine yet.
Before companies like FreeValve can start production of their
camless engine variant, a lot of testing remains before they can
put it out on the market, which will lower production costs.
Until then, consumers will not be able to purchase and spread
this technology across the globe, so its impact will not be felt
for a few years.
Once production does start however, more energy and
resources must be used to manufacture the components
necessary to control the new valvetrain. This includes slightly
more energy consumption from extra sections of factories and
more materials used for the production of the actuators.
Another question that is raised then, is if the benefits can
outweigh these drawbacks and make the camless engine worth
the effort.
Outweighing the Disadvantages
To address these concerns, engineers need to focus on the
main reasons why this technology was created in the first
place, which is to reduce emissions while increasing efficiency
and performance. With the expected gains claimed by
FreeValve of 50% less pollutants and 30% more power, this
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SOURCES
[1] “Internal Combustion Engine.” Britannica Online for Kids.
2017. Accessed 2.26.2017.
http://kids.britannica.com/eb/art-66070/Cross-sectionshowing-one-cylinder-of-a-four-stroke-internal
[2] R. Seethaler, J. Zhao. “A Fully Flexible Valve Actuation
System for Internal Combustion Engines.” IEEE/ASME
Transactions of Mechatronics. Vol. 16, No. 2. 4-2011. pp.
361-370
[3] F. Badin. Hybrid Vehicles From Components to System.
Paris, France: Editions Technip. 2013. pp. 84-86
[4] W. S. Chang, J. G. Kassakian, T. A. Keim, T. A. Parlikar,
D. J. Perreault, Y. H. Qiu, M.D. Seeman. “Design and
Implementation of an Electromagnetic Engine Valve Drive.”
IEEE/ASME Transactions of Mechatronics. Vol. 10, No. 5.
10-2005. pp. 482-494
[5] J. Hirsch. “253 million cars and trucks on U.S. roads;
average age is 11.4 years.” Los Angeles Times. 6.9.2014.
Accessed 1.26.2016.
http://www.latimes.com/business/autos/la-fi-hy-ihsautomotive-average-age-car-20140609-story.html
[6] “Sources of Greenhouse Gas Emissions.” US
Environmental Protection Agency. 1.24.2016. Accessed
1.10.2017.
https://www.epa.gov/ghgemissions/sources-greenhouse-gasemissions#transportation
[7] E. Mohamed. “Modeling and performance evaluation of an
electromechanical valve actuator for a camless IC engine.”
International Journal of Energy and Environment (IJEE). Vol.
3, No. 2. 2012. pp. 276-294
[8] “FreeValve Technology.” FreeValve. Accessed 1.10.2017.
http://www.freevalve.com/technology/freevalve-technology/
[9] C. Woodard. “Here’s How the Camless Engine of the
Future Works.” R&T.com. 10.19.2016. Accessed 1.26.2017.
http://www.roadandtrack.com/new-cars/cartechnology/videos/a31223/how-camless-engine-works/
[10] “Learn About Sustainability.” US Environmental
Protection Agency. 10.18.2016. Accessed 3.26.2017.
https://www.epa.gov/sustainability/learn-aboutsustainability#what
[11] “IEEE Code of Ethics.” IEEE. Accessed 3.26.2017.
http://www.ieee.org/about/corporate/governance/p7-8.html
ACKNOWLEDGMENTS
We would like to thank our co-chair Danielle Broderick
for taking some time out of her busy schedule to revise parts
of our paper. Special thanks also go out to our chair Jared
Andes, who has provided very helpful professional feedback
about the technical content of the paper. Finally, another big
thanks to our writing instructor Michael Cornelius for giving
us great feedback throughout the writing process.
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