Symposium Proceedings_full book

Mechanical Engineering
Symposium 2014/2015
Organized By;
Mechanical Engineering Society
Faculty of Engineering
Universristy of Peradeniya
Co-Sponsored By;
Litro Gas Lanka Ltd.
Associated Motor Ways (Pvt) Ltd.
25th July 2015

Mechanical Engineering Symposium 2014/2015
Mechanical Engineering Society, University of Peradeniya - July 2015 01
Message from the Dean, Faculty of Engineering
University of Peradeniya
After the very first attempt in conducting
the Mechanical Engineering Symposium in 2013,
it is indeed very encouraging to see the second
symposium being organized in 2015. I congratulate
the department of Mechanical Engineering for the
teamwork to materialize the event and guiding the
students to engage in activities linking the industry.

The Mechanical Engineering Symposium essentially wraps around the
objectives of raising awareness on research and development activities of the students
among industrial representatives and the academics of the Faculty and obtaining
feedback. This also provides a valuable opportunity for the students to demonstrate and
advertise their projects to a wider audience while promoting a research a culture. The
feedback emanating from the symposium will be of immense value to the students, and
to the department of Mechanical Engineering in strengthening links with the industry.

The Symposium includes guest lectures conducted by experienced engineers,
who are experts in specialized areas of Mechanical Engineering, and planned with
presentations of projects of the final year students. I am sure you will find that the breadth
and depth of the presented works have room for further research, improvements and
developments.

Mechanical Engineering Society, University of Peradeniya - July 201502
I would like to take this opportunity to thank the staff and the students of the department
of Mechanical Engineering, who made this event a reality. Further on behalf of the
Faculty of Engineering, I convey my sincere gratitude to the experts & the Engineers
from the industry, the sponsors, and the University of Peradeniya, for wholeheartedly
supporting this event.
Prof (Eng.) Leelananda Rajapakse,
BScEng Peradeniya, MEng, PhD London, MIESL, MIIAR, MASHRAE, CEng,
MIMechE
Message from the Head, Department of Mechanical
Engineering, University of Peradeniya
I am very pleased to be given this opportunity
to deliver this message as the head of the department
for the occasion of the 2015 Mechanical Engineering
Symposium. I would like to begin this message by
thanking those who contributed to making this event a
success.
As one of the founding departments in the
Faculty of Engineering, University of Peradeniya,
the Dept. of Mechanical Engineering has contributed tremendously by producing a
large number of nationally and internationally acclaimed Engineers who have made
significant contributions to the field of Engineering since its inception in the early fifties
in Colombo as a part of the University of Ceylon. The primary aim of the department
has been to disseminate knowledge and technology through quality teaching, research
and its application in mechanical and allied disciplines. In order to produce Mechanical
Engineers with a solid foundation in theory and practice we have a dedicated faculty of
having post graduate qualifications from world renowned universities. They conduct
research and development activities in dynamic systems, energy conversion, thermo-
fluids, design & manufacturing, and control systems in addition to regular teaching
activities. Through internships and student societies we provide the students’ the
opportunity to enhance their leadership, management and teamwork skills.
In addition to the undergraduate programme, the Dept. successfully conducts
a regular Masters programme in “ Building Servicers Engineering” and other post
graduate degrees towards MPhills and PhDs. Also, the department provides consultancy
servicers and conducts various professional and technical training programmers through
its industrial hub, Engineering Design Center, University of Peradeniya.

Recently we have focused more on developing stronger relations with the
industry in order to gain a better understanding of the current expectations of the
industry and to help develop the technology in the. Accordingly we have strengthened
the industrial consultative committee by including highly experienced engineers
covering a wider range of Mechanical Engineering disciplines. From such strengthened
activities, we are continuously trying to mould our graduates to fit well into the current
engineering practice of the world. The Mechanical Engineering Symposium 2015 is one
such effort where we hope to showcase some of our outstanding student talents. This
year we have selected representative few undergraduate projects as an indicator of of
the academic and professional achievement of our graduates. In the past many of our
undergraduate projects have received IESL and IMechE awards for best undergraduate
student project. We wish to use this Symposium as an avenue to recognize and showcase
undergraduate projects with such potential capability. We hope that this recognition
will provide an added motivation for the present and future undergraduates to perform
at their best. Also, I am sure that, our students will get at least a glimpse of the industry
expectations and its activities by means of the invited guest lectures and the discussions
that will ensue.
Finally I would like to conclude by wishing that this Symposium, organized for
the second time by the Mechanical Engineering Society, will be a valuable experience
for the participants, presenters, sponsors, organizers, and the department of Mechanical
Engineering in general.
Dr. (Eng) S. D. G. S. P. Gunawardane
BScEng Peradeniya, MEng, PhD Muroran, MIESL, CEng
Message from the Chairman, Mechanical Engneering
Symposium 2014/2015
On behalf of the symposium committee, it is
a pleasure to welcome you to the second Mechanical
Engineering Symposium of the Department of
Mechanical Engineering, University of Peradeniya
scheduled to be held on the 25th July, 2015 at the
Faculty of Engineering Seminar room. As the oldest
mechanical engineering department in Sri Lanka, this
department has flourished over the years producing
some brilliant academics and professionals to both
local and international markets. This year, the Department of Mechanical Engineering
produced a girl as “the Batch top” in Engineering Faculty and probably it is the first time
in mechanical engineering departments in Sri Lanka. Also it produced 3 first classes,
6 second class upper divisions and 15 second class lower divisions. The department
of mechanical engineering provides various courses for developing background in
mechanical engineering of the students in areas of generation, conversion, control and
utilization of power, the construction of mechanical devices, machines, mechanisms,
instruments and electro-mechanical and thermo-fluids equipment. The growing
faculty staff including former heads of the department, talented students and the active
leadership is the strength of the department. In addition, the facilities of this department
are seeing a rapid growth. A new boiler system has been added to the department, and
base on it, new courses and lab experiments are to be scheduled. During last year, a M.Sc.
course in mechanical engineering has been started and it is conducting very successfully.
The students of the mechanical engineering society (MES) and the staff of the
department organize the mechanical engineering symposium second time in row. The
aims of this symposium are to present the student’s projects to a professional audience
and also expose the department and students to the industry. The first symposium
was organized as a half a day program and this year it has been extended further. It

has been planned to organize this as a one-day program in future and include it to the
department calendar. This symposium is student-staff-initiated, student-staff run event
that provides a networking opportunity for undergraduate students, staff, and industry
representatives. This symposium is a meeting ground for mechanical engineering
student-staff and various scientist, specialist and researches from the industry.
The successful organization of a symposium requires the talents, dedication
and time of many volunteers and strong support from the sponsors. We extend our very
special gratitude and appreciation to our sponsors, the mechanical engineering society,
the members of symposium comities and the staff. It should be mentioned here the
enormous support we received from Vice Chancellor University of Peradeniya Professor
Atula Senaratne, Peradeniya Engineering Faculty Alumni Association (PEFAA) and
Engineering design center (EDC). At this point we wish to thank authors who put so
many efforts, first in completing successful projects and preparing their submissions.
We extend our sincere thanks to guest lecturers. Finally, I would like to acknowledge
the head of the department of mechanical engineering Dr. Gunawardane and the dean
faculty of engineering Professor Rajapakse. Without their remarkable support, we would
not have such an excellent event.
For your relaxation and enjoyment a tea is provided after the first session and
you may use this time to get together with your colleagues and friends as well as get
acquainted with new ones and also lunch will be provided at the end of the symposium.
We hope that you will find this symposium both enjoyable and valuable. Hope you will
join with us again next year.

Dr. (Eng) W. P. D. Fernando
BScEng Moratuwa, MSc Sweden, PhD Sweden

Agenda
Department of Mechanical Engineering
25th July 2015

Agenda
08:30 – 09:00 Registration
Opening Ceremony
09:00 – 09:05 Lighting the traditional oil lamp and National
Anthem
09:05 – 09:10 Welcome address by the Chairman, Symposium
2014/15
09:10 – 09:15 Address by the Cheif Guest, The Vice Chancellor,
09:15 – 09:20 Address by the Dean, Faculty of Engineering,
09:20 – 09:25 Address by the Head, Department of Mechanical
Engineering, Faculty of Engineering, University of
Peradeniya
Invited Lectures, Project Presentations and
Promotion Sessions
09:30 – 10:30 Invited Lecture 1
10:30 – 11:00 Presentation of final year projects (2 projects)
11:00 – 11:30 Refreshments

11:30 – 12:30 Invited Lecture 2
12:30 – 13:15 Presentation of final year projects (3 projects)
13:15 – 13:55 Promotion sessions for companies
13:55 – 14:00 Vote of Thanks by the President, Mechanical
Engineering Society
Fellowship
14:00 onwards Lunch and Fellowship
Keynote Lectures
25th July 2015

Engineering Project Management and Manufacturing
Operations
ABSTRACT
Project management is a system originally developed within the construction
industry for controlling schedules, costs, and specifications of large multitask projects.
In recent years, Project management has been adopted as discipline that can be applied
to all industries, and can be particularly effective in the manufacturing industry.
Manufacturing relies heavily on quality and time to market to build and retain its
customer base, so these two factors—quality in particular—need to be the focus during
the manufacturing process. When a project management methodology is applied to the
manufacturing process, its tools and techniques can ensure that quality standards are
met and the time to market is efficient so called “Delivery Commitment”. This will be
achieved primarily through the techniques of planning, scheduling, risk management,
quality management, quality assurance and quality control, and lessons learned.
Manufacturers have discovered that project management’s time-tested
techniques dovetail neatly with the organization current thinking on quality control
and management in a highly competitive global marketplace and recognized the
Project Management Office abbreviated to PMO, which is a group or department
within a business, agency or enterprise that defines and maintains standards for project
management within the organization. Engineering as supporting function as well
as Engineers as Specialist in the organization’s PMO plays a vital role in engineering
project management in Manufacturing and High Technology Operations, focuses on
Lakmal Kelum
Loadstar (Pvt) Ltd.
Ekala, Sri Lanka.
Phone: +94 77 6913866
Email: lakmal.kelum@camoplastsolideal.com

the dramatic increase in the use of high-tech machinery in industrial operations, and
seamlessly integrates high-tech themes into a general discussion of project management.
PMO can be established as central function in large organization and purpose is
to develop & manage Project Management Process & Knowledge Area Mapping to Plant
Ops Plan & Central Services Projects. Engineering PMO can define the tactics through
proven feasibility studies and prepare business proposals for future financial years for
budgeting in Capex and Opex and also take the approved Capex & Opex initiatives for
the current year operating plan as well as strategic initiatives derived under Strategic
Plan for long run probably about 3 to 5 years.
Engineering Project in PMO starts with problem analyzing. One of the famous
and proven systematic approache, firstly introduced by Toyota Japan but promoting
now as benchmarked way of templating an organization problem in simple ISO A3
sheet called A3 problem analysis. A3 is a structured problem solving and continuous
improvement approach, is also called as SPS which stands for “Systematic Problem
Solving”. It can take all stakeholders to common forum trough one format but unlimited
to practice the most suitable problem analyzing tools such as Fishborne, Value Chain,
Cause and Effect, etc and to select best option (solution) through decision making
matrix, etc. This systematic approach takes stakeholders through 6 steps starting from
Current situation, Goal & Objectives, Analyis Root Cause, Countermeasures, Action
Plan & Conclusion. Once A3 is presented and approved from the organization structure
not only from top to bottom but from bottom to top called TLBO abbreviated to Team
Leader Based Organization, whole society within the organization can feel the real
gravity of the problems that organization have. With respect to Classical Engineering
Project Management which starts from project elements such as budget, time, scope and
resource planning, the Modern Engineering Project Management in a PMO starts from
problem analysis whereas no reasons to be alienated to compromise on understanding
the organization top priority requirement.
Capital investments shall be strategic but crucial in the organization competitive
position in future market. It is not always a critical factor to consider the financial return
of an investment in investment decision making. Since most of organization has set
of org values and the benefit of an investment shall be consisted to such values. It is a
good practice to group the main benefit of investment or inititatives into pillars ranging
from Financial Benefits (FB), Market Growth (MG), Process Improvement (PI), People
Engagement (Health & Safety, Training) – (PE).
Engineers not only in Project Management function even in production,
marketing, maintenance are to be a competent planner and a presenter for their own
function in the organization in planning and monitoring in Ops Plan called Operating
Plan. Operating plan define the function related initiatives in stratergic and operation
type wise, objectives, tactics, funding requirement, Roles and Responsibilities (R&R),
Beneficiary, Sponsors, Expected Benefit, KPI target and actual.
On approved initiatives PMO Engineers define the project charter and project
documentations. A good PMO is always equipped with a one page format of project
charter introduction, project operating plan, risks analysis. Even though many institutes
coach students in project management, the young engineers in industry are far away of
thinking the ability to model a problem or an assignment given in an organization in
to a project management model. End results are hopeless, time waste, frustrating, poor
communications, poor formalization and authorization.
In the engineering sector, having the ability to manage projects well to get
things done is what counts. When the pressure is on to accomplish a project deliverable,
there can be bumps in the road that can challenge even the best of project managers.
Engineering of any form is not for the faint of heart, especially in an agile project
management environment. Here are some obstacles you may face and how to overcome
them for project management success.
• Scope Creep
Perhaps one of the biggest challenged for engineers involved in project
management is when the scope of work begins to unravel into an uncontrolled series
of changes and additions – also known as scope creep. This can occur at any stage of a
project, but it must be carefully managed with a system for tracking requests for changes
and an approval process before work can be modified.

• Poor Team Communication
If a project team does not communicate well, any project can fail. That’s why it’s
important to have an internal project management system where notes and appropriate
dialogue can take place, as well as regularly scheduled project meetings. Clear and
respectful communication should be your goal.
• Underestimating Time and Materials
Before launching into any project, whether it’s new or a modified scope of
work, be sure to get an accurate picture of the resources you will need to get it done on
time. This includes time and materials, as well as the technical personnel who have the
right skills to work on each element of the project. By planning these aspects carefully
upfront, your business can be more profitable.
• Bureaucratic Red Tape
Nothing reduces a project to chaos more so than a bunch of red tape brought
on by too much corporate control and interference. While not all of this can be avoided,
the vast majority of it can be handled by having a capable project manager at the helm.
In this way, there are less people trying to manage a project, when one esteemed PM is
in charge.
• Lack of Knowledgeable Staff
Not having project managers and engineering staff who know what they are
doing can destroy even the most innovative of projects. Taking the time to recruit and
hire the best team members can ensure project success for the long term. It’s advisable to
do this as early as possible in the project cycle.
Thebestengineeringprojectsaremanagedbysuccessfulteamsworkingtogether
and working towards a common goal. By working out the above issues, organizations
current and future projects can be more streamlined. Using a staffing agency can help
business line up the right candidates for each project, based on their unique skill sets and
project experience.
Mechanical Engineering or sub derived so called specialist engineering
disciplines lay the basis to engineering project management in requirement
identification, scope defining, problem analyzing and engineering design process owing
to the concepts including mechanics, kinematics, thermodynamics, materials science,
structural analysis, and electricity. Mechanical engineers use these core principles along
with tools like computer-aided design, and product lifecycle management to design and
analyze manufacturing plants, industrial equipment and machinery, heating and cooling
systems, transport systems, aircraft, watercraft, robotics, medical devices, weapons, and
others throughout the course of their PMO model.
Mr. Lakmal Kelum obtained his BSc from the
UniversityofPeradeniyaandwontheProf.Mahalingam
Prize for the year 2006. Troughout the course of 9 year
carrier path, he got the opportunities of working local
and foreign soil in diverse environment ranging from
construction sites to manufacturing facilities. Currently
being employed as the Senior Project Manager and
Head of PMO dedicated to strategic engineering
projects in the organization earlier called Loadstar
Pvt Ltd which function as the largest manufacturing
facility in a Globally recognized off-road tire product specialist company named CAMSO
established in global market at 4th place. The speaker has found many challenges in
meeting and being align with organization strategic and operational tactics and has gain
globally recognized management practices in engineering project management.
ABOUT THE SPEAKER

New Trends and Development in Automobile Sector and
Adaptation of Local Technical Competencies
ABSTRACT
Automobile industry in the world is considered as the most rapidly developing
industrial sector next to information technology. After introducing the first mechanical
automobile by Karl Friedrich Benz (1844 – 1929) in early 1900’s technology had been
developed over a period of 100 years aggressively to the current state to offer “auto
flying” machines.
Today, the automobile industry is no longer valid only with “pure mechanical”
version of engines, it moves towards combination of mechanical and electronic concepts
called “Mechatronics.” Mechatronics concepts are quite common and widely used in
latest automobiles to enhance the power and the efficiency to ascertain the competitive
edge against ordinary traditional engines while creating high customers’ acceptance.
Sri Lanka as a middle income consumer market, and country with open
economy polices, open to world to acquire these latest technologies similar to other
developed countries and people in the country have been privileged to import any
kind of sophisticated automobile machines to the country based on their need and the
purchasing power.
It is a fact and the industry data shows that, scientific maintenance and repairs
carried out accordingly to the manufacture guideline is essential for these automobiles
Chaminda Rohitha Wanigarathne
Associated Motorways (Pvt) Ltd.
Colombo, Sri Lanka.
Phone: +94 77 4652900
Email: chaminda.wanigaratne@amwltd.com
to run in long term without technical defects. Thus, in order to maintain these latest
Automobiles which are packed with various electronic components and systems, it is
essential to have an in-depth knowledge on latest principles and theories and hands on
experience on “Mechatronics” (related to automobile) diagnostic techniques.
Due to the “Technological GAP” existing between the local mechanics and the industry
development, it is resulted refraining ordinary mechanics to attend on repairs of these
latest technological developed automobiles and instead they try on “trial and error”
methodology to fix problems. This resulted in poor handling and technical mess up of
these vehicles and finally the customer losing confidence on using these assets.
In line with these issues, this paper is focused on the international technology
competencies,localtechnologicalcapabilitiesandfactorshinderingeffectiveassimilation
if technology in automobile sector.
Mr. Chaminda Wanigarathna finished his BSc in
Engineering at the University of Peradeniya and did his
Masters in Business Administration at the University
of Moratuwa. He served as a sector manager in
the Southern Development Authority (SDA) in Sri
Lanka during 2000 to 2004 and held managerial
posts in leading automobile companies in Sri Lanka.
The speaker has engaged in many assignments and
developments related to the automobile engineering
and currently serves as the General Manager of Group
After Sales at Associated Motorways (Pvt) Ltd, a fullt owned subsidiary company of Al-
Futtaim Motor Comapany, UAE, since 2013.
ABOUT THE SPEAKER

Selected Projects
25th July 2015

Paper I
Development of an Obstacle Avoidance
System for
a Quad-Rotor UAV
25th July 2015

Development of an Obstacle Avoidance System for
a Quad-Rotor UAV
A Quadrotor is a Vertical Take-Off and Landing (VTOL) vehicle, which
is increasingly being used for many purposes such as mapping, surveillance and
transportation tasks [1]. For the quad-rotor to be used in an open environment, its
stability must be ensured for safety. The overall objectives for the two semester project
was the development of such a quadrotor. Specifically there were two objectivs a.) the
implementation of a attitude stabilizing controller with a large region of stability, and b.)
the implementation of an obstacle avoidance system.
The open source codes that are available in the internet to freely download and
use are developed based on linearized models and PID controllers. These PID controllers
are applied by linearizing the system around a point. This is not good for large and
unexpected maneuvers of the quadrotor. Thus, commercial use requires a controller that
has a larger region of stability. The controller and the attitude estimator as described in
[2, 3] were used together as a replacement for the open source linear PID controller.
Towards implementing the non-linear PD controller, first, the quad-rotor was
mathematically modelled considering the rigid body dynamics of the quad-rotor [4, 5].
This mathematical model was used to simulate the system in MATLAB and to verify the
K.G.B. Gamagedara, A.P.S.K. Gunasekara, K.A.D.N.G. Gunathilake and
D.H.S. Maithripala
Peradeniya 20400, Sri Lanka.
Phone: +94(081)2393600; Fax: +94(081)2393600
Emails: kanishkegb@gmail.com, gunasekarask@gmail.com,
kadgayashan@gmail.com, mugalan@gmail.com

controller. Then it was converted in to Arduino compatible C since the used controller
board is an Arduino board. This controller board has an inertial measurement unit
consisting of a 3-DOF gyroscope, a 3-axis accelerometer and a 3-axis magnetometer.
The knowledge of the attitude generated by the observer is very crucial for
debugging the programs that were used to implement the PD controller. Therefore, a
platform independent real-time simulator was developed in order to get readings from
the quad-rotor and to plot its attitude on a computer screen in real-time. C++ and a
few open-source libraries were used for the development of this simulator. In addition,
the quad-rotor was modelled using a CAD software to find the inertia values and other
physical parameters. Rotor+Motor+ESC units were calibrated using an experimental
setup.
The obstacle avoidance system was developed using sonar sensors. Four sensors
were used to detect the obstacles around the quad-rotor. First, an algorithm for the
obstacle avoidance system was developed for a single sonar sensor. This was simulated
first. As the simulation results were acceptable, the algorithm was further developed to
be used with all four sonar sensors. The developed algorithm was verified using realistic
rigid body 3D simulations. The simulation worked as expected and can be seen in the
Youtube video link provided in [6].
Furthermore, the hardware implementation of the obstacle avoidance system
was also completed. The obstacle avoidance system uses four sensors that give analogue
signals as outputs. Since there is only one set of pins available for analogue readings
in the controller board, interfacing all four sensors was a challenge. This difficulty was
overcome by using I2C wiring mode as discussed in [5].
The code, which was used for the simulation, was converted into Arduino
compatible C and tested using manual motion of the quad-rotor. Results show that the
algorithm works as expected. Flight testing of the algorithm requires the quad-rotor to
hold a given altitude. At the time of completion of the project, it had not been possible
to implement an altitude holding controller. Thus, unfortunately, the obstacle avoidance
system could not be tested in real-time flight at the time of completion of the project.
This project was conducted after the project deadline and the controller
displayed robust properties and good disturbance rejection. Some of these results have
been currently submitted to ICIIS 2015.
REFERENCES
[1] Robert Mahony, Vijay Kumar, and Peter Corke; Modeling, Estimation and
Control of Quadrotor, IEEE Robotics & Automation Magazine, September 2012
[2] D. H. S. Maithripala and J. M. Berg, “An Intrinsic PID Controller on Lie Groups”.
Automatica, 54(0), pp. 189 – 200.
[3] D. H. S. Maithripala and J. M. Berg, “An Intrinsic Robust PID Controller on Lie
Groups,” pp. 5606–5611, 2014.
[4] Development of an Obstacle Avoidance System for a Quad-Rotor UAV, ME 406 –
Mechanical Engineering Group Project I, June, 2014
[5] Development of an Obstacle Avoidance System for a Quad-Rotor UAV, ME 407 -
Mechanical Engineering Group Project II, October, 2014
[6] Simulation for Four Sonar Sensors : http://youtu.be/PDX6RmF_hdQ

Paper II
Design of a Stabilized Platform for Carrying
Small Weights
25th July 2015

Design of a Stabilized Platform for Carrying Small Weights
INTRODUCTION
With current advances in technology, the world is seeing new methods of
transportation facilities in production lines. Stabilized platforms are used in many
industrial applications, for example: Robotics and Autonomous systems, scientific
research equipment with sensitive sensor units etc. A model of self-stabilizing platform
has been designed and fabricated in the department of mechanical Engineering,
University of Peradeniya, Sri Lanka as a final year under graduate project. This concept
uses four bar mechanism and the mechanical linkages actuated by servo motors, the
servo motor worked under control signal which receive the control signals from the
Arduino UNO board. It contains two platforms and they are connected in parallel. Servo
motors and Arduino UNO board are placed in the bottom platform and gyroscope and
accelerometer are fixed on the top platform. The top platform and bottom platform are
connected with four steel bar linkages, in which two are connected with servo motors and
the motion of the other two linkages, are controlled using a guider. When stabilizing the
platform it is important to tilting it from the initial stable position. In order to measure
the tilt angle the platform was changed from the stable position. The gyroscope was used
to measure the tilt angle. In real applications it need much faster and a much accurate
reading of the tilted angle. To accomplish this requirement an electronic gyroscope was
used. It was mounted on the top platform to measure the top platform’s tilt angle in
respect to the initial position of the top platform (horizontal position).
R. Rohini, S. Jesudason, P. Rajithkumar, N.Jathavan and D. Randeniya
Phone: +94(081)2393600; Fax: +94(081)2393600
Emails: rajithkumar29@yahoo.com,

WORKING PRINCIPLE OF THE SYSTEM
The ADXL322 gyroscope was chosen as a sensor because it is relatively
inexpensive sensor with a reasonable sensitivity. The Arduino platform is an open source
electronic prototyping system. It composed of two parts; the Arduino Uno board and the
Arduino IDE (Integrated Development Environment). The Arduino IDE is the software
environment used to create the programs, called “sketches,” that will be executed by the
Arduino hardware. The IDE uses a modified C language compiler to build, translate, and
transmit the Code to the microcontroller board. The HS-422 servos were used in this
model. The servos are rated to 6V max. Usually the servos are powered using an Arduino
board 5V power pin. If servo requires more power than the Arduino board can supply,
the servos are powered using an external power source, a 9V battery with 5V, 1A power
Regulator. The servos supporting and controlling the top platform and were arranged
to control by the Arduino board. A close up view of the servo arrangement and axis is
illustrated in Fig.1. The servos were installed on the bottom platform as shown in Fig
1. The servo motors were used to attach the linkages, via the linkage, to themselves and
the upper platforms. The link attached to the rotating servo horn allows the platforms
to rotate independently and keep them in horizontal position. An IMU board (3 DOF
Digital combo board) was chosen as the sensor to measure the tilt of the upper platform
with horizontal. The data was read from gyroscope and accelerometer channels are
processed in the Arduino logic with the necessary information to maintain the upper
platform level always in horizontal through sending the signal to servo to change the
servo angle. Because of 50ms sensitive the error will send to Arduino then the Arduino
program will give the output to servo motor. Then the platform will be stabilized. If error
Figure 1: Prototype of the final model.
is zero, Arduino will give output of zero tilt angles to the servo motor then it will tilt zero
degree.
RESULTS AND DISCUSSION
In both test cases the platform performed as expected. A quantitative
measurement was completed and the water level results showed the platform’s accuracy
to be approximately 80%. This accuracy value was determined by observing how much
of the water level was parallel with horizontal position. When a heavier mass was placed
on the level, the accuracy decreased to about 75%. Some extreme angles were tested and
the platform maintained consistent behavior within the mechanical limits. It was also
observed that the platform was more accurate when the weight was in the Centre or
balance with center position. This phenomenon was likely due to the flexibility of the
linkage components and the mechanical properties of the servos act on. The results of
the testing proved that the platform was performed as expected.
CONCLUSIONS.
This platform was designed as a stabilized platform for carrying cargo. Cargo
implies the heavy weights. For the completion of this project, it is required to fabricate
the model. For a platform carrying heavy weights, the selection of materials are difficult
because the materials should be strong enough to carry the cargo. Due to cost and
design limitations a self-stabilized platform for carrying small weights was designed
and fabricated. In the beginning of the project, the designed platform model used a
six bar linkage mechanism. Two parallelogram linkages are connected to the bottom
Figure 2: Testing mechanism

platform, while another two linkages are connected the top platform with the bottom
structure. Due to the complexity of the model and difficulties in controlling the devices
and the motion of linkage bars the six bar linkage model is reduced to four bar linkage
model which uses two servo motors, a gyroscope and an accelerometer. After the design
is reduced to four bar mechanism the buckling of the linkages was another problem
faced. Using guider mechanism, the problem was solved. The program is written until
the measured angle become zero which implies that the top platform is in horizontal
position. Due to the gyro drift the error percentage in the final circuit output is high;
to overcome this problem complimentary filter is used. Complimentary filter uses
gyroscope and accelerometer measurements, for that IMU board is used as sensor which
consists of gyroscope and accelerometer. For the programming purpose Arduino UNO
board is used. It is a new section for us, due to that we have to study about programming
Arduino board. It helps us to improve our knowledge in electronics and circuit design.
An appreciable knowledge in servo motor and calling its library is also needed. By doing
the project we gained more knowledge and it is a great opportunity for us to study about
these sections.
REFERENCES
[1] Joseph Edward Shigley, Theory of Machines and Mechanisms, 3rd Edition,
1980, pages 27-69.
[2] Riazollah Firoozian, Servo Motors and Industrial Control Theory, 2009, pages
3-16 and 62-67.
[3] Naveen Agrawal, Kinematics - Analysis of Mechanisms: Methods and
Techniques, 1st Edition, 2009, pages 17-36.
[4] http://www.fao.org/docrep/s1250e/s1250e1i.html. Web. 10 august 2014.
[5] www.theplasticshop.co.uk Web. 29 September 2014.
Paper III
Investigation of the Performance of an
Autonomous Mechanical Pitch Control
System for a Small Scale Wind Turbine
25th July 2015

Investigation of the Performance of an Autonomous
Mechanical Pitch Control System for a Small Scale Wind
Turbine
INTRODUCTION
Wind energy can be identified as one of the major sources of energy used in
the renewable energy sector. During the past few decades, researchers have managed
to generate new knowledge in area of wind energy harnessing, providing solutions to
address the significant problem of increasing global energy demand. Since the inception
of wind turbines, researchers have mainly focused on two aspects, namely, optimum
power extraction from the wind and regulation of the generated power.
Power regulation is a vital factor in any power extraction device. In the context
of wind turbines, power regulation refers to controlling speed of the rotor which is
coupled to a generator. By controlling the rotor speed smooth operation of the generator
is ensured by avoiding unnecessary power peeks. This controlling action will further
ensure safety of the structure of the wind turbine. As a power extraction device, wind
turbine should mainly function as to extract power in an optimum manner. Thus, it
should curtail operation above the designed wind speed and simultaneously extract
optimum power below the designed wind speed. In a broader sense, the functionality of
the wind turbine can be described as a device which should extract maximum amount
of energy in low wind speeds below the rated speed and curtail operating at high wind
J.A.L.T Jayasuriya, K.A.L Srilal, I.M.A.S Illankon, K.G.V Maduranga,
W.R.S.U.A Higgoda and S.D.G.S P Gunawardane
Phone: +94(081)2393600; Fax: +94(081)2393600
Emails: lahirutj@gmail.com, lalitha4srilal@gmail.com,
imsandaru@gmail.com, vimaduranga@gmail.com, ubayahiggoda@gmail.com
sdgspg@gmail.com

speeds. Based on the degree of freedom of the turbine blades two categories can be
identified, namely, fixed and variable pitch turbines. There are power regulation systems
for both these types, such as, Elektro, Enag and Quirk, Stalling, Fly-ball, Jacobs and
Soviet stabilizer systems [1].
In this study, a simple and an autonomous mechanical pitch controlling
mechanism is proposed addressing the complexity, capital cost and maintenance issues
of the aforementioned and ones that are currently in use in high end power regulation
systems.
Pitch controlling system
In this study, a spring system is used together with two cams to form a cam and
a follower arrangement (Figure 1.a).
Figure 1: Pitch controlling arrangement
The blade is fixed to the cam shaft maintaining an eccentricity with the actual
blade axis as shown in figure 1.b. This is the unique feature of this design. When the
aerodynamic forces are imposed on the blade the eccentricity helps to generate a
torque about the shaft axis which is counterbalanced by the cam arrangement generat-
ing a pitching motion of the blade.
METHODOLOGY
To carry out this investigation a 200 W class two blade turbine with the pitch
control arrangement was used. In addition to the physical model, a mathematical
model was also developed using Simulink toolbox of MATLAB 2009 software by
using governing equations of the basic aerodynamic relationships and considering the
operation principles of different components of the system.
The figure 2.a. elaborates mathematical model used in devising the Simulink
model. The equations used in each sub section of the model has been clearly shown in
the figure 2.b.
(a)
(b)
Figure 2: Mathematical model used in Simulink

The cam profile, stiffness of the spring and the eccentricity can be identified as
the dominant parameters that govern the degree of the pitching motion of the blade at a
particular wind speed. The progress which has been carried out up to now is to evaluate
the performance of the system as a whole for a given set of parameters.
Results and Conclusions
A 200W class two blade turbine was implemented and tested at a high altitude
location near Balumgala, Kadugnnawa. Rotor speed was observed at different wind
speeds at the field testing. The gathered data is shown as field test data in figure 3 with
other observed simulation results for fixed blade instance and pitch controlling instance.
It can be clearly seen from figure 3 that the rotor speed increases in an
exponential manner with wind velocity in all three instances. It should be also noted
that, the simulation with the pitch controlling system follows the fixed blade condition
up to 3 m/s and deviates beyond that point. This is the point where the power curtailing
action comes in to effect. The field test data also yield a general trend which shows the
deviation from the fixed blade trend from a wind speed of 3 m/s. Due to various practical
difficulties occurred in obtaining field test data, such as sudden change of wind direction
causing turbulent conditions and lack of steady flow wind condition for a considerable
amount of time might have caused the field test data to be less reliable.
Figure 3: The comparison of the experimental and simulation results
However, it can be clearly concluded that beyond wind speeds of 3 m/s the
effect of the proposed pitch controlling system plays a significant role. This type of
characteristic behavior is desirable and meets the objective of adopting a speed regulating
control system.
Since the functionality of the speed regulating mechanism is qualitatively
assessed and verified an interested researcher may verify this in a more quantitative
manner with more reliable operating conditions. This study identified some dominant
parameters which affects the pitch controlling action of blade. It is also interesting to
carefully look into the effect of each of this parameter and its significance on the pitch
controlling system.

REFERENCES
[1] Gouriẻrẻs, D. L., Wind Power Plants-Theory and Design, 1st ed., Pergamon
press, Oxford, 1982, pp. 60-72.
[2] Burton, T., Jenkins, N., Sharpe, D. and Bossanyi, E., Wind Energy Handbook,
2nd ed., John Wiley & Sons, 11, pp 349-353.
[3] Condaxakis, C.G., Christakis, D.G., Frandsen, S.T., and Eboueya, M., Passive
Controlled Wind Turbine Blades, Wind Energy Conference, France, March 1999, pp
337.

Paper IV
Design, Fabrication and Testing of a Screw
Type Turbine
25th July 2015

Design, Fabrication and Testing of a Screw Type Turbine
Abstract
In Sri Lanka, hydro power is the main source of electricity generation and
undoubtly the cheapest. Most of the sites available in future development of conventional
small hydropower are nearly comming to an end. Therefore, some other alternatives are
necessary to exploit further ehancement of small hydropower potentials. There are large
number of irrigation canels and other water supply systems available islandwide where,
the water flow rates are high but the available water head are comparatively low. For
susch situations, Archimedies water turbines (screw turbine) are identified as a feasible
option and in this study we investigated the performance of such turbine at laboratory
environment.
Introduction
A Screw turbine usually consists about three or more helix shaped blades
mounted on a central shaft. This shaft and blade assembly is put into a trough and is
set to an angle. When water enters the top of the screw, considered without any kinetic
energy, filling it to about the midpoint of the diameter. As the water flows downhill it
creates a torque on the screw and causes it to turn. The screw is connected to a gearbox
to step up the rotation speed and turn the generator. These turbines are identified as
environment friendly, low initial cost, low maintanence, and most importantly low head
H.M.R.B Herath, H.M.P Madara, W.S.A Soysa, W.M.C.S Wijerathne
and S.D.G.S P Gunawardane
Phone: +94(081)2393600; Fax: +94(081)2393600
Emails: ruchcha.h@gmail.com, hmpamod@gmail.com,
soysa-sujana348@gmail.com, chaturaw90@gmail.com, sdgspg@gmail.com

turbine. The screw type turbine which is based on the Archimedes screw is theoritically
87% effecient (water-to-torque efficiency) and water-to-wire the efficiency goes up to
77% [1].
This main objective of the project is to find technical competancy of fabrication and
testing of a screw tubine using loacaly available technology and understanding the
charateristics of key design parametrs by laboratory testing. Further it is expected to do
a proper field test with larger scale device which is capable of producing electricity for a
small domesticated lighting circuit.
Methodology
A model was designed and the key element of the turbine, the screw was
fabricatedwithaluminum.Themodelparametrswereselectedbasedonthelitretaureand
standards in the industry[2]. The screw dimentions are 250 mm outer diameter,125mm
inner diameter, 1140 mm long, and an angle of 61.3o with a head of 1m . Then the screw
was fitted with a friction type torque measuring system and assembeled at a open chanel
flow flume of the fluid mechanics laboratory at the Faculty of Engineeing, University of
Peradeniya ( see figure 2). The test rig was assembled such a way that the inlet flow rate
can be changed and the induced torque can be measured. The flow rate and the load
torque were taken as the variable parametrs and changing those values series of data
set were taken for speed of of rotation of the turbine. Based on the data, high efficientcy
operating range was identified for the specific screw design. Tthe experimental setup is
shown in figure 1.
Figure 1: The experimental setup
Results and discussion
Figure 3 shows the variation of water to torque efficiency and the power for
diffrent loading values for the tubine. Those curves represent the best results obtained
and the maximum efficiency obtained is 51 % with an output power of 65 W. Theoretically
the screw’s efficiency is 87.5% and still there are possibilities to improve the system[1].
We identified that the low level of accuracy of fabricated screw as the main cause for
this efficiency drop. The screw element was fabricated by rolling aluminum sheets by
pressing them on a mould. Then the shaped sheets were welded to the main shaft and to
the ajoint sheets. Therefore, deformations happens due to welding heat generations and
lack of strength of the sheet materials. So, the final product deviated from the expected
design. Also, the scaling effect comes to the aggrivation of leake due to propotional
increments of gaps between cahanel and turbine blades. To overcome fabrication
difficulties and scaling effects, it was proposed to fabricate a larger scale screw with steel
sheets, which is easier to weld and low cost. Also, it is important to fabricate the screw
lighly to facilitate easy starting. Therfore, like wind turbines, composite design of screw
with glass fiber would be more appropriate in this application. For that we need a good
moulding system beforehand.
In conclusion, the main objectives of the project was met, however fabricating
the screw with the expected accuracy and dimensions were not entirely successful. For
the success of this project it is necessary to fabricate an accurate screw, maybe with the
Figure 2: The completed setup at the testing bay

change of material used and change of design accordingly with the existing technology.
REFERENCES
[1] http://www.3helixpower.com/archimedes-screws/
[2] Gerald Müller, James Senior “Simplified theory of Archimedean screws”,
Journal of Hydraulic Research Vol. 47, No. 5 (2009)
[3] Chris Rorres, “The turn of the screw: Optimal design of an Archimedes screw”,
Journal of Hydraulic Engineering / January 2000.
Figure 3: The comparison of efficiency and power
w
Paper V
25th July 2015
Design and Simulation of Hydrostatic Power
Transmission System (HST) of Flap Type
Wave Energy Device for Regular Waves

Design and Simulation of Hydrostatic Power Transmission
System (HST) of Flap Type Wave Energy Device for Regular
Waves
Abstract
This paper presents the characteristics of HST (hydrostatic power transmission)
system of a top hinged caisson mounted flap type resonant wave energy device called
‘Pendulor’ for regular wave conditions. The device mainly consists of a hinged flap which
is placed at the nodal point of the standing waves that are generated inside a caisson.
The hinge resembles a hydraulic pump which is connected to HST energy conversion
system. The HST system mainly consists of serially connected pump, accumulators and
variable displacement hydraulic motors and electrical generator assembly. When the
flap resonates with the incoming waves, it harnesses the maximum power if the energy
conversion system is tuned to match with the hydrodynamic impedance of the flap. For
regular waves, the tuned system has shown 80 % conversion efficiency.
Introduction
Energy extracting from the ocean waves has become a trend in finding
alternative energy sources. Among the various types and methods, the Pendulor type
(oscillating pendulum with ocean waves) is one of the prospective option to use in Sri
Lanka specially integrating with breakwaters. Figure 1 shows the artistic impression of
250 kW Pendulor device at the southern coast in Sri Lanka [2]. The top hinged flap
oscillates in caisson by the excitation force generated by the standing wave created
H.M.S. Sanjaya, D.C. Pathiray, N.S.B. Rathnayaka, R.A.D.P. Ranasinghe
and S.D.G.S P Gunawardane
Phone: +94(081)2393600; Fax: +94(081)2393600
Emails: supunsanjaya05@gmail.com, pathiray@gmail.com,
dhanujayar@gmail.com, saliyaefac@gmail.com, sdgspg@gmail.com

inside the caisson. The flap is placed at the node of the standing wave in order to get the
maximum horizontal wave forces. The attached HST system to the flap converts wave
energy to electrical energy.
Frequency domain model
Figure 1: Artistic impression of 250 kW Pendulor device (Watabe, 2001)
Figure 2: Schematic of flap device in a caisson
H
h
d
l
Figure 2 shows the schematic of top mounted flap type wave energy device
operates by the standing waves generated inside the caisson of width b and the water
depth h. The wave height is H and the frequency is . The flap is considered as the same
width as the caisson and it is hinged at distance l from the free water surface.
Equation of motion in the frequency domain is shown in equation 0.
Where, I0
; inertia of the flap, ; frequency dependant added inertia due to fluid
motion with the flap, , Bp
; damping torque by the hydraulic pump, Kk
; restoring moment
of the flap due to gravity, K; the restoring coefficient due to water chamber and M0
; the
excitation moment by the waves.
General solution of the above can be taken as,

where,

Energy absorption by the power takeoff system (PTS) within time
period of to , is shown in equation 2. The energy of incoming regular
wave during a wave period T is shown in equation 3. Efficiency ( ) can
thereby be derived as shown in equation 0.

(0)

(0)

(0)
Accordingly, the maximum energy can be harnessed when
and . This condition is called resonance and
impedance matching condition of the Pendulor where theoretically 100 % efficiency can
be achieved. Due to limitations of the operation of the system, the practical approach for
optimising the system s to change the Bv parameter.
The HST system
Figure 3 shows the schematic of the HST system of twin Pendulor system. A
double acting cylinder is used as the hydraulic pump of the system. The HST system is
designed with two subsystems; one sub system is pumped with hydraulic fluid when the
flap moves in one direction only. Thus the other sub system pumps hydraulic fluid when
the flap moves in to the other direction. Those two sub systems are separated by non
return valves as shown in figure 3.
Figure 3: The HST system
GA
A
Pump Pump
A
P P
A
G
Controller
Controller
24 MPa
Hydraulic motor
Controller
Variable speed hydraulic motor with a control system is used to change the
damping torque given by the hydraulic pump on the pendulum. The displacement of the
motor is controlled according to some algorithms in the simulations, by the feedback of
the system hydraulic pressure.
The attached accumulators will soft the hydraulic flow variations and the
controllers will scene the hydraulic pressure and control the displacement of the
hydraulic motors. Thus the hydraulic flow rate could be controlled.
The HST system has to be designed to operate in a suitable pressure range to
maintain desired damping to the flap. Anyway in practice, the operating pressure will
vary around the mean operating pressures (design pressure). Also, the range of operating
pressure is much less than the difference between the mean operating pressure and
zero. This means that the variation of the pressure at the cylinder with time has nearly a
square wave pattern at every time the flap changes its motion of rotation. Therefore, the
damping effect of the T can be more accurately modelled with Coulomb damping. The
accuracy of the square wave pattern will be increased as the operating pressure range gets
reduced. Therefore the characteristic equation must be modified as shown below. The
only parameter that could be practically altered is T. The plus or minus mark represents
the change of damping effect as the pendulum changes its oscillating direction.

Results
HST system characteristics for regular waves
The optimising conditions changes according to the control algorithm used in
the control system. Initial simulations were carried out using a linear control algorithm.
(Simulations for the regular sine waves) In those simulations, it was observed that there
is an optimum mean pressure value in which the system will have a maximum output.
The value can be changed by changing the linearity of the algorithm.
Other tests were carried out using a non-linear algorithm which was used to try to match
damping effects on both pendulum and HST system. In this situation, the output power

was kept increasing as the mean operating pressure increases.
Initially the HST system was simulated to be compatible with the lab apparatus.
The wave height was 0.1 m, wave period was 2 s and calm water height was 0.3m.
A double acting hydraulic cylinder was taken as the pump of the system. It
had a cross section of 0.00126 m^2 at its maximum cross sectional side. The simulation
was carried out with accumulators of 4l and the variable displacement motors with
maximum of 28 cm3/rev displacement.
As shown in figure 4, the operating pressures of the HST system (nearly 3.5
bars) were around the accepted region of 3.6 bars.
The figure 5 shows oscillation of the pendulum at the optimum operating point.
It was a nearly pure sine curve which is preserved at lower operating pressures but with
reduced efficiency.
When the operating pressure increases, the curve gets distorted from the sine
curve, resulted with a reduced efficiency comparing to the optimum condition.
Figure 4: Variation of the operating pressure with time
Figure 5: Oscillation of the pendulum
Figure 6: Oscillation of the pendulum
The figure 6 shows the power output from the system. The initial rice of the
power was a result of the charged pressure in the accumulators.

Although the controller was linear its performances were good. It had a
considerable efficiency and the phases of the oscillation velocity of the pendulum and
the torque induced on the pendulum was matched. But it was needed a fine tuning as
shown in the figure 5 the angular velocity is deviated from a sine curve.
Figure 7: Variation of the efficiency with a linear controller algorithm
Figure 8: Oscillation velocity of the pendulum and the torque induced on the pendulum
(T)
Although the non-linear controllers were simulated, they were only simulated
to lower pressure values and the damping matching was not sufficient because the
frequency matching was not carried out.
Further research is promoted here because; although a simple linear algorithm
was able to give sufficient output, non-linear algorithm may improve results and may
compatible better with changing wave frequency.
Then the current HST system was remodelled to a 250 kW scale. The HST
system characteristics of the proposed plant have been obtained for the regular waves.
The site details are h=4 m, B=3 m, d=18 m, l=4 m, H= 1 m, lg=4.5 m. Significant wave
period is 12 s and significant wave height is 1 m.
The outputs of the system were compared with other researchers and they were
quite accurate.
Discussion
Even using a simple control algorithm for the controller: nearly an efficiency
of 80% was received for the simulation. Therefore at the optimum conditions, a simple
linear controller would be sufficient for implementing.
But the disadvantage is that the system may be incapable to deliver, when the changes
are present in the frequency of the ocean waves. The system must be capable to adjust
itself according to the frequency of the ocean wave. The main limitation of this kind of a
controller is that the system must operate on an optimum mean pressure to deliver the
best.
When using a linear controller, the mean operating pressure of the HST system can
be changed by changing the parameters of the linear equation of the controller. As the
frequency of the ocean wave changes, the mean operating pressure of the system could
be changed by changing the controller characteristics. Therefore if the HST system has
more than a simple linear controller, it could be work better in irregular wave conditions.

Mechanical Engineering Society
Committee Members 2014/2015
Senior Treasurer - Dr. W. P. D. Fernando
President - D. M. S. S. Dissanayake
Secretary - N. L. Kariyawasam
Vice President - Dileepa Warnasinghe
Junior Treasurer - Danushka Vidanage
Editor - J. H. M. P.Herath
Committee Members
Tharindu Willarachchi
Chathuranga Kahawaththe
Malinga Perera
Kalpani Rasangika
K. L. M. Silva
conclusion
1. The HST system is theoretically modelled for regular wave climatic
conditions. The available frequency domain model is used to establish the time domain
model.
2. The operating conditions/outputs of the HST system were inside the aimed/
optimum/needed ranges.
3. The system did have an optimum mean operating pressure for a certain
operating condition.
4. The mean operating pressure of the HST system could be changed by
changing the parameters of the linear controller.
reference
[1] T. Watabe, H. Yokouchi, S.D.G.S.P. Gunawardane, B.R.K. Obeyesekera and
U.I. Dissanayake, Preliminary Study on Wave Energy Utilization in Sri Lanka, Eleventh
(2001) international Offshore and Polar Engineering Conference.
[2] Watabe. T, Utilization of the Ocean Wave Energy, Fuji print company Ltd.
Muroran, Japan, 2007.
[3] Modelling and control of oscillating-body wave energy converters with
hydraulic power take-off and gas accumulator, Anto´ nio F. de O. Falca˜o

Notes
Organizing Committee
Symposium Chairman
Dr. Asanga Ratnaweera
Organizing Committee
Sandun Kokawala
Supun Dilanka
Rumali Rathnayake
Dilrukshi Prasangika
Thilini Jayathissa
Nalaka Amarasiri
Viraj Kavindra
Shashikala Senevirathna
Buddhika Aththanayaka
Sponsorships & Financing
Tharindu Rasnakawewa
Kalana Karunarathna
Publications & Editorial
Thimira Wijewardana
Sithira Rajapakshe
Ishara Madusanka
Kavindu Fernando

Notes

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