Master of Philosophy (M.Phil.)

Permanent URI for this collectionhttp://192.248.9.226/handle/123/18723

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Now showing 1 - 14 of 14

item: Thesis-Abstract
Incorporating biological signals for understanding user intentions for intelligent wheelchair
(2022) Abayasiri RAM; Jayasekara AGBP; Gopura RARC; Kiguchi K
Over the years Intelligent wheelchairs which can gather information from the envi ronment to make decisions for itself have been developed to fulfil the needs of the wheelchair users. To improve the human robot interaction between the wheelchairs and the users, wheelchairs come with several types of controllers which are designed to meet the customer satisfaction. Use of biological/ electrophysiological signals for improved user satisfaction has an increasing demand all over the world. In order to incorporate user intentions for the navigation purposes and object manip ulation purposes of an intelligent wheelchair electrophysiological signals can be used. Due to the high signal to noise ratio and the fact that it does not require invasive surgical procedures to extract the electrophysiological signal, electromyography is used for above mentioned purposes. Since, electromyography is generated due to the motion intention ofthe user, it can accurately represent the intention of the user. Furthermore, the number of working muscles required to build a controller for above mentioned pur poses is high. Hence, it can be seen that most of the existing electromyography based controllers use muscles associated with hand movements as they can generate sev eral number of combinations of muscle activations depending on the hand movement/ grasping pattern. However, these are invalidated if the wheelchair user is suffering from physical conditions like trans-radial amputation where the upper limb is ampu tated between wrist and the elbow, trans-humeral amputation where the upper limb is amputated between shoulder and elbow and the partial/complete paralysis of the upper limb. This thesis proposes an Electromygraphy based controller for navigation and intelligent object manipulation of the wheelchair, which can be used even by the wheelchair users with trans-radial amputation, trans-humeral amputation and partial limb function. Any wheelchair user who has partial/complete function of biceps brachii of both of the arms, triceps brachii of the dominant arm and the right and left ster nocleidomastoid of the neck, can use the proposed electromyography based controller. Moreover, the controller is enhanced with vision sensor and a proximity sensor for the intelligent object manipulation task. By using the common user preferences and his previous experience in arranging objects on a wheelchair tray controller was designed to be user friendly. Experiments were carried out to monitor the adaptability and usability of the proposed Electromyography based controller among different users. Results confirmed that it can be used by any user after calibrating it for few trials. A human study was performed for different subjects to monitor whether patterns emerge in placing objects in different situations. After implementing a clustering algorithm, common locations and arrange ments for object placements were identified. Furthermore, experiments were performed after building the whole system inside the CoppeliaSim simulation environment, to monitor the capability of the proposed system in manipulating and arranging objects according to the user preferences in different situations. Simulation results proved that the proposed system can place the objects in accordance with the results of the human study.
item: Thesis-Abstract
Energy - based control in HAVC systems in commercial buildings to optimize the building energy performance
(2022) Walgama SR; Kumarawadu S; Pathirana CD; Walgama, S,R, (2022). Energy - based control in HAVC systems in commercial buildings to optimize the building energy performance [Master's theses, University of Moratuwa]. Institutional Repository University of Moratuwa. http://dl.lib.uom.lk/handle/123/20862
The severity of the emerging environmental problems and the criticality of a future energy crisis with associated socio-economic quandaries are becoming strengthen along with the inevitable growth of energy demand due to the ever-increasing population and urbanization. Inspired by this, many state-of-the-art and efficient engineering advancements under demand side management are being conceptualized, developed, and examined via worldwide research for several years. As one of the largest global energy consumers, buildings, and their Heating, Ventilating and Air Conditioning (HVAC) systems acquire substantial attention regarding optimal and efficient energy management. Nevertheless, longer computational time, complicated implementation, deficient occupants’ thermal comfort and productivity, and limited practicability and feasibility of most of the approaches that have been proposed, have demotivated the industry applications even though they offer consequential designing and operating advancements to the system. Therefore, the expected building energy performance can be further extended by unraveling these encountered disputes with novel energy saving strategies. This research concentrates on energy optimal operation of HVAC systems by addressing secondary chilled water pumping system, temperature setpoint management, cooling water system, and temperature controllers in Air Handling Unit (AHU). Three different innovative energy saving strategies to determine the optimal number of chilled water pumps to be operated with their optimal speed, optimal zone temperature setpoint schedule, and optimal cooling water flow rate with a setpoint of the chilled water supply temperature have been proposed along with the consideration of system constraints, safety, occupant thermal comfort, and satisfaction. In addition, a novel temperature controller that can be utilized in AHU has been introduced and the performance in comparison with available controllers has been studied. Simulation results obtained via the case studies authenticate the effectiveness of the introduced approaches and encourage the functioning of these strategies in real engineering systems due to the inherent simplicity, robustness, and less computational complexity.
item: Thesis-Full-text
Multi-resolution analysis based ANN architecture for fault detection in DC microgrids
(2020) Jayamaha DKJS; Arachchige LNW; Rajapakse AD
DC microgrids present an effective means for integration of renewable energy sources to the utility network while offering clear benefits such as higher efficiency, better compatibility with DC sources and loads and simpler control, compared to its AC counterpart. However, protection challenges associated with DC networks, such as lack of frequency and phasor information, lack of standards, guidelines and practical experience are of particular concern. Lack of effective solutions for protection of DC networks presents a major barrier for the widespread integration of DC microgrids to the utility network. There are several conventional DC network protection techniques employed in wide range of DC network applications in the fields of telecommunication, data centers and shipboard networks. However, straightforward application of these conventional techniques for protection of DC microgrids is impracticable due to intermittent nature of DGs connected to the network, operation in both grid-connected and islanding mode and high sensitivity to fault impedance. Hence, for the safe operation of DC microgrids, it is imperative to have reliable fault detection and relay coordination scheme. This thesis presents novel fault detection and grounding scheme for DC microgrids. In the proposed fault detection scheme, fault features contained within fault transients are extracted using a multi-resolution analysis technique and are used alongside an ANN classifier scheme for fault classification. To evaluate the performance, a comprehensive study on the proposed scheme is presented. Simulation based test results asserted that the proposed technique has accurate, fast and intelligent fault detection capability compared to existing DC protection schemes. Possible improvements to the current technologies and future directions for research, which could enhance the protection of DC microgrids, are also outlined in this thesis.
item: Thesis-Full-text
Stability and security analysis of India-Sri Lanka HVDC interconnection
Perera, AGCU; Rodrigo, WDAS; Wijayapala, WDAS
This thesis concentrates on the stability performance of HVDC-HVAC interaction of the transnational HVDC interconnection between Sri Lanka and India. This transmission line under consideration since mid-1970 and the prefeasibility study was done by India in cooperated with Sri Lanka together. In this study it was focused on modeling the HVDC link between Indian and Sri Lankan power grids with the basic control system and studying the transient stability performance of the HVDC interconnection under the Sri Lankan transmission network perturbed conditions. The complete system was modeled on PSCAD/EMTDC software. The complete system was divided into five subsystems while modeling as, rectifier side AC source, converter transformers and converters, DC transmission line, HVDC control system and inverter side detailed Sri Lankan network. The simulations were done for steady state conditions, for system accuracy verification and for different system perturbed conditions. The analysis was done based upon the maximum power curve, Short circuit ratio (SCR) and time domain analysis. It was found that; modeled Sri Lankan network is a strong network for the proposed HVDC interconnection in steady state condition. However, there is a considerable impact on the stability of HVDC-HVAC interaction under different perturbed scenarios of Sri Lankan AC network. This study discusses the results obtained from the qualitative and quantitative analysis. was The results obtained from this study can be taken as guidance during the planning and designing stage of the proposed DC interconnection to have an idea on stability of the AC-DC interaction. The DC power operating curve, maximum DC power infeed to inverter side Sri Lankan network, AC system strength behavior during different disturbances, time domain faults behavior, impact ofAC system impedance on the stability are the facts which are discussing in this thesis. Therefore, this thesis can be consider as guidance for the planning stage ofthe proposed interconnection
item: Thesis-Full-text
Under frequency load shedding for power systems with high variability and uncertainty
Bambaravanage, DYT; Kumarawadu, S; Rodrigo, A
Emergency load shedding for preventing frequency degradation is an established practice all over the world. The objective of load shedding is to balance load and generation of a particular Power System. In addition to the hydro and thermal generators each with less than 100 MW, today, the Power System of Sri Lanka is comprised of three coal Power Plants: each has a generation capacity of 300 MW, Yugadanavi combined cycle Power Plant (300 MW generation capacity) and a considerably extended transmission network. To cater consumers with high quality electricity, a reliable Power System is a must. Therefore, it has become timely necessity to review the performance of the present CEB Load Shedding Scheme and suggest amendments where necessary. The objective of this research is to explore a better Under Frequency Load Shedding Scheme (UFLSS) which can face probable contingencies and maintain stability of the system while catering more consumers. The suggested UFLSSs can address the recent changes taken place in the Sri Lanka Power System too. A simulation of the Power system of Sri Lanka was designed with software PSCAD. Its validity was checked through implementing actual scenarios which took place in the power system under approximately-equal loaded condition and by comparing the simulated results and actual results. Then a performance analysis was done for the Ceylon Electricity Board (CEB) Under Frequency Load Shedding Scheme which is being implemented in Sri Lanka. Having identified the drawbacks of the CEB Under Frequency Load Shedding Scheme, the new UFLSSs (LSS-I and LSS-II) were suggested. The Load Shedding Scheme – I (LSS-I) is designed based on power system frequency and its derivative under abnormal conditions. Without doing much modification to the prevailing UFLSS, and utilizing the available resources, the suggested LSS-I can be implemented. The LSS-II gives priority for 40% of the system load for continuous power supply, and it is comprised of two stages. During the stage-I, approximately 30% of the load is involved with the Load Shedding action. During the stage-II, the disintegration of the power system is done. This involves the balance 30% of the load. At 48.6 Hz the disintegration of the power system takes place. By disintegrating the power system at the above mentioned frequency, all islands as well as the national grid can be brought to steady state condition without violating the stability constraints of the Sri Lanka power system. During disintegration of the Power System, special attention must be paid for: • Generation & load balance in each island and in the national grid. • Reactive power compensation in islands and in the national grid. • Tripping off of all isolated transmission lines (which are not connected to effective loads). Through simulations the effectiveness of the UFLSSs were evaluated. They demonstrate better performance compared to that of the currently implementing CEB scheme. Results highlight that the UFLSS should exclusively be specific for a particular Power System. It depends on factorssuch as power system practice, power system regulations, largest generator capacity, electricity consumption pattern etc.
item: Thesis-Abstract
Parameter optimization of CNT production using Sri Lankan graphite by arc discharge methods
(2014-08-12) Gunasekara, RMSJ; Karunadasa, JP; De Alwis, A; Samaranayake, L
Since their discovery in 1991 by Iijima, carbon nanotubes have been of great interest. The key advantages of these structures are their electronic, mechanical, optical and chemical characteristics, which open a way to a variety of applications. These properties can even be measured on single nanotubes. For commercial application, large quantities of purified nanotubes are needed. Different types of carbon nanotubes can be produced in various ways. The most common techniques used nowadays are: arc discharge, laser ablation, chemical vapor deposition and flame synthesis. Fundamental and practical nanotube researches have shown possible applications in the fields of energy storage, molecular electronics, nano-mechanical devices, and composite materials. Real applications are still under development. This project is basically focused on arc discharge method of CNT production using Sri Lankan vein graphite. Sri Lankan graphite is unique due to its perfect crystalline structure and the higher as mined purity compared with that of commonly available flake graphite. This type of natural resource is found mainly in Sri Lanka. Detailed study on flake and vein graphite was carried out in this study as one of its objectives. Also SEM and TGA analysis of the multiwall carbon nanotubes are discussed. Special technique for comparing diameters of multiwall wall carbon nanotube was developed by using TGA. Further, the cross section analysis was carried out for the arc scoot to analyze the formation of the nanotubes on the cathode. Another objective here was to identify the optimum parameters for the production of CNT using the arc discharge method. Arcing time, current, chamber inert gas, chamber pressure and the type of the electrode were the variables. Arcing current around 100 A, pressure around 700~900Torr and arcing duration around 60s with helium as the inert gas were the optimize conditions. Key words: Vein Graphite, CNT, MWCNT, Arc discharge, Nanotube
item: Thesis-Abstract
Parameter optimization of CNT production using Sri Lankan graphite by arc discharge methods
(2014-08-04) Gunasekara, RMSJ; Karunadasa, JP; De lwis, A; Samaranayake, L
Since their discovery in 1991 by Iijima, carbon nanotubes have been of great interest. The key advantages of these structures are their electronic, mechanical, optical and chemical characteristics, which open a way to a variety of applications. These properties can even be measured on single nanotubes. For commercial application, large quantities of purified nanotubes are needed. Different types of carbon nanotubes can be produced in various ways. The most common techniques used nowadays are: arc discharge, laser ablation, chemical vapor deposition and flame synthesis. Fundamental and practical nanotube researches have shown possible applications in the fields of energy storage, molecular electronics, nano-mechanical devices, and composite materials. Real applications are still under development. This project is basically focused on arc discharge method of CNT production using Sri Lankan vein graphite. Sri Lankan graphite is unique due to its perfect crystalline structure and the higher as mined purity compared with that of commonly available flake graphite. This type of natural resource is found mainly in Sri Lanka. Detailed study on flake and vein graphite was carried out in this study as one of its objectives. Also SEM and TGA analysis of the multiwall carbon nanotubes are discussed. Special technique for comparing diameters of multiwall wall carbon nanotube was developed by using TGA. Further, the cross section analysis was carried out for the arc scoot to analyze the formation of the nanotubes on the cathode. Another objective here was to identify the optimum parameters for the production of CNT using the arc discharge method. Arcing time, current, chamber inert gas, chamber pressure and the type of the electrode were the variables. Arcing current around 100 A, pressure around 700~900Torr and arcing duration around 60s with helium as the inert gas were the optimize conditions.
item: Thesis-Full-text
A Robust natural language question answering system for customer helpdesk applications
(2014-05-30) Samarakoon, LT; Kumarawadu, S
This thesis describes a restricted-domain question answering system which can be used in automating a customer helpdesk of a commercial organization. Even though there has been an increasing interest in data-driven methods over the past decade to achieve more natural human-machine interactions, such methods require a large amount of manually labeled representative data on how user converses with a machine. However, this is a requirement that is difficult to be satisfied in the early phase of system development. In addition, the systems should be maintainable by a domain expert who is less technically skilled when compared to a computer engineer. The knowledge based approach that is presented here is aimed at maximally making use of the user experience available with the customer service representatives (CSRs) in the organization and presents how true representative data can be collected. The approach takes into account the syntactic, lexical, and morphological variations, as well as a way of synonym transduction that is allowed to vary over the system's knowledge base. The query understanding method, which is based on a statistical classifier, a ranking algorithm based on Vector Space Model (VSM) and a pattern writing process, takes into account the intent, context, and content components of natural language meaning as well as the word order. A genetic algorithm-based method is presented for finding the domain specific ranking parameters. An evaluation of the approach is presented by deploying a system in a real-world enterprise helpdesk environment in the telecommunication domain. The evaluation shows that the system is able to answer user questions with an accuracy of 94.4%. Furthermore, maintenance of the deployed system is carried out by CSRs successfully.
item: Thesis-Abstract
Real-time detection and tracking of vehicles with lane detection
(3/23/2012) Fernando, WSP; Udawatta, L; Pathirana, P
In this research, a computer vision based procedure for navigating an autonomous vehicle safely in a sub-urban road under an unstructured environment was described. This was analyzed in two main areas. Namely; an on road object detection method, where we are only concerned of detecting cars, and a novel method in detecting road lane boundaries. For the detection of vehicles (cars) from an on-road image sequence taken by a monocular video capturing device in real time and an algorithm of multi resolution technique based on Haar basis functions were used for the wavelet transform, where a combination of classification was carried out with the multilayer feed forward neural network. The classification is done in a reduced dimensional space, where Principle Component Analysis (PCA) dimensional reduction technique has been applied to make the classification process much more efficient. Then, the other approach used is based on boosting which also yields very good detection rates. In general, boosting is one of the most important developments in classification methodology. It works by sequentially applying a classification algorithm to reweighed versions of the training data, followed by taking a weighted majority vote of the sequence of classifiers thus produced. For this work, a strong classifier was trained by the discrete adaboost algorithm and its variants. In this thesis, a novel algorithm for detection of lane boundaries was presented. Initially, the method fits the CIE L*a*b* transformed road chromaticity values (that is a* and b* values) to a bi-variate Gaussian model followed by the classification of road area based on Mahalanobis distance. Then, the classified road area acts as an arbitrary shaped region or a mask in order to extract blobs resulting from the filtered image by a two dimensional Gabor filter. This is considered as the first visual cue. Another visual cue of images was employed by an entropy image. Moreover, the results from color based visual cue and visual cue based on entropy were integrated following an outlier removing process. Finally, the correct road lane points are fitted with Bezier splines which act as control points that can form arbitrary shapes. The algorithm was implemented and experiments were carried out on sub-urban roads.
item: Thesis-Abstract
Economic and environmental impacts of Carbon & Energy taxes in the power sector
(11/30/2011) Siriwardena, KKW; Wijayatunga, PDC; Attalage, RA
This report presents the results and analysis of a study conducted with the objective of investigating the impact on economy wide emissions due to a carbon and energy taxes levied within the electricity generation sector of Sri Lanka. An Input-Output decomposition technique is used to analyze four types of effects that contribute to the overall reduction in equivalent Carbon, NOx and SO2 emissions. These four effects are; fuel mix effect (i.e. the change in emissions due to variation in fuel mix), structural effect (i.e. change in emissions due to changes in technological coefficients), final demand effect (i.e. the change in emissions associated with changes in final demand) and joint effect (i.e. the interactive effect between or among the fuel mix, structural & final demand effects). The polluting fuel sources (e.g. coal) are less preferred under these tax regimes. Of the four effects change in fuel mix in thermal electricity generation and change final demand for electricity were found to be the main contributors in achieving economy wide emission reductions. It was found that a minimum of $50/tC of carbon tax or $1.0/MBtu of energy tax is required to have a significant impact on economy-wide emissions in the Sri Lankan context. This results in an increase in electricity generation cost by approximately Rs 1 /kWh and Rs 0.65 /kWh under carbon and energy tax regimes respectively. The reduction in emissions is also strongly coupled with the value of price elasticity of electricity. Also the study concentrates on tackling the barriers for the promotion of clean and energy efficient technologies in Sri Lanka. Barriers for renewable sources; wind and biomass (dendro thermal) and cleaner technologies; IGCC (coal) and LNG fired combined cycle were identified, based on a survey and strategies are proposed to tackle the major barriers. Analytic Hierarchy Process is used to rank the barriers and the strategies are proposed to address the three major barriers for each technology. For wind a Feed-In-Tariff, geographical diversification and capacity building in commercial banks are suggested. For dendro investment incentive and streamlining of wood production are proposed. Incorporating environment costs into the planning process and delayed implementation are suggested for IGCC and LNG.
item: Thesis-Abstract
Clean energy & regulatory interventions for greenhouse gas emmission mitigation in the Sri Lanka power sector
Prasad, WD; Wijayatunga, P
Renewable Portfolio Standard (RPS) is rapidly emerging as a popular mechanism among policy makers to increase the penetration of renewable in the electricity markets, requiring the electricity supply industry to include a minimum level of electricity generation from renewable energy sources. Sri Lankan energy policy has set a target of 10% of grid electricity by 2015 to come from non-conventional energy sources (NCRE). Mini-hydro, biomass including dendro power and wind energy, which have been identified as the three leading, sustainable, non-conventional forms of renewable energy promoted in Sri Lanka for electricity generation to feed into the national grid. The present installed capacity of grid-connected non-conventional renewable energy based electricity generation in Sri Lanka is around 100 MW and these plants are mainly connected to the primary distribution system. All these plants contribute to the nation's energy requirement generating only a small fraction of total generation amounting to approximately 2.5%. The longterm least-cost power generation expansion plan has given rise to the installation of oil-fired and coal-fired thermal plants to meet the increasing demand. This process does not give adequate consideration to the alternate supply-side options such as those based on NCRE. The study presented in this thesis first investigates the impact of alternate generation options like NCRE based technologies, clean fuel options and reciprocating diesel engines with small capacities in the Sri Lankan power system considering Traditional Resource Planning based on minimizing total economic cost. . The mam intention of this study IS to investigate technological and regulatory interventions especially the impact of the RPS of 10% on the least-cost power generation expansion plan of Sri Lanka considering available renewable technologies as supply-side options together with their technical potential and economic feasibility. The study also examines the impact of these interventions on overall power sector emissions and. the greenhouse gas emissions- (GHG) in particular. The sensitivity of the outcomes of the 10%-.!3-PSto different supply side interventions are also presented in the thesis. It has been found that the 10% RPS target by 2015 can be achieved with an additional cost burden of US$ 57.25 million on the government. The results also show that mini hydropower is the best NCRE based technology which needs minimum financial incentives when achieving the target. Wind power and dendro power require substantial government incentives if they are to playa role in RPS.
item: Thesis-Abstract
Remote meter reading over power distribution lines
Gamage, K; Karunadasa, JP; Dias, D; Ranaweera, A
The thesis presents the development of a simple technique for remote reading of utility meters using the low voltage power distribution network. Remotely reading electricity, gas and water meters have distinct advantages over traditional metering methods. Several communication technologies have been designed and implemented for this purpose using wireless techniques, telephone lines, power transmission and distribution lines. In this study, the last one has been selected as the basis for the development of a remote meter reading system applicable to Sri Lanka. Power line communication over low voltage distribution lines is a cost effective method for data transmission. But it is complex due to large number of branches, tapings, transformers, different line configurations etc., that are present in the distribution network. The main task of this research is to develop suitable techniques for transfer of data over this network. The basic concept of data transmission in this application is the change of voltage and current wave at the supply end and the load end respectively of the power system. A series of current pulses are generated representing the data to be transmitted from the consumer end. Similarly, a series of voltage pulses are generated at the supply end to represent the commands to be sent to the consumer. These current and voltage pulses are superimposed with the line current and the line voltage at the load end and the supply end respectively on the power line signal. The prototype system presented in this thesis shows simulation as well as experimental results relating to the data transmitter, and the software design for the communication subsystem interfacing the meter to the distribution lines. A series of measurements are also carried out to find a suitable time of the day tor the data transmission. Associated problems such as harmonics generated due to the insertion of data and the effects of load changes in the distribution network are also discussed.
item: Thesis-Full-text
Determination of earth resistivity profile in mul ti layer soil
Dhrmadasa, IT; Lucas, JR
Soil structure investigation is very important in many Engineering applications. The Electrical Engineers extensively use the soil structure information when designing grounding systems. The sub soil structure with its resistivity distribution has a direct impact on the performance of the grounding system, that is, the electrode resistance and the surface voltage distribution. In Applied Geophysics a variety of soil structure investigation methods are used. Among these, the Electrical Resistivity Method has become very popular due to its simplicity. The resistivity method measures apparent resistivity of the ground to a direct current flow. The field data contain apparent resistivity values and geometry information. When the field data is interpreted, it detects the discontinuity of resistivity distribution in a location of interest. This interpretation can be done One dimensionally( lD), Two-dimensionally (2D) or Three-dimensionally (3D) depending on the application's necessity. The interpretation of resistivity field data using inversion techniques may be ambiguous. Conventional ID DC resistivity inversion techniques include graphical methods requiring interpolation and judgment and computer based iterative calculation methods. The work presented in this thesis, investigates a new resistivity data inversion tool, Neural networks(NNs). Neural Networks are capable of solving several types of problems, including parameter estimation, parameter prediction, pattern recognition, classification and optimization. Also recently the use of Neural Networks in the Geophysics parameter estimation problems has Shown strong results. With this recent trend in the applicability of the NN's for the non linear geophysical inversion problems NN's is proposed as the inversion tool for parameter estimation or Sub surface interpretation. The main intention of this study is to investigate the applicability of NNs as a fast and accurate inversion tool for field resistivity data. The study considers the approach and capabilities of the NNs in inversion of field resistivity data to interpret ID, 2D or 3D sub soil Structure with resistivity discontinuities.
item: Thesis-Full-text
Obstacle avoidance for unmanned surface vehicles: simulations and experiments
Jayendra, RG; Kumarawadu, S
Sri Lanka ports authority and many other organizations are increasingly interested in the use of Unmanned Surface Vehicles (USV) for harbor security and surveillance applications. USVs can be used to collect information, samples and perform experiments inside a harbor or outside by. Navigating through ships and other objects. This research study is focused on finding algorithms for obstacle avoidance (OA) of USVs. The initial paradigm that is used to establish the solution was the OA of Unmanned Ground Vehicles (UGV). The algorithms developed for UGV were implemented practically with the limitations of hardware. Then, effort is taken to apply those algorithms to the surface vehicles with some modifications. In this study, a novel OA algorithm is proposed for static obstacles based on the Morphin algorithm. This proposed algorithm and the previous algorithm which is developed based on ground vehicles are compared with the potential field method. Static OA without dynamic OA is not helpful for unmanned vehicles on sea. A lot of researches have been carried out to avoid dynamic objects, but have failed to find an optimum solution although comparatively good approaches have been presented. Intelligent techniques have been rarely applied for dynamic obstacle avoidance. In this research, the effectiveness of applying intelligent or mathematical techniques for path prediction of dynamic obstacles is discussed with simulations to pick the best for a given situation. Then a noval projected dynamic obstacle area method is presented to avoid dynamic obstacles effectively. Comparative results are presented at the end to prove the strength "of the noval dynamic obstacle area method.

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