Abstract:Conventional robotic manipulators consist of touch and vision sensors in order to pick and place differently shaped objects. Due to the technology development and degrading sensors over a long period, the stereo vision technique has become a promising alternative. In this study, a low-cost stereo vision-based system, and a gripper to be placed at the end of the robot arm (Fanuc M10iA/12) are developed for position and orientation estimation of robotic manipulators to pick and place different shaped objects. The stereo vision system developed in this research is used to estimate the position (X, Y, Z), orientation (𝞡y) of the Center of Volume of four standard objects (cube, cuboid, cylinder, and sphere) whereas the robot arm with the gripper is used to mechanically pick and place the objects. The stereo vision system is placed on the movable robot arm, and it consists of two cameras to capture two 2D views of a stationary object to derive 3D depth information in 3D space. Moreover, a graphical user interface is developed to train a linear regression model, live predict the coordinates of the objects, and check the accuracy of the predicted data. The graphical user interface can also send predicted coordinates and angles to the gripper and the robot arm. The project is facilitated with python programming language modules and image processing techniques. Identification of the stationary object and estimation of its coor-dinates is done using image processing techniques. The final product can be identified as a device that converts con-ventional robot arms without an image processing vision system into a highly precise and accurate robot arm with an image processing vision system. Experimental studies are performed to test the efficiency and effectiveness of used techniques and the gripper prototype. Necessary actions are taken to minimize the errors in position and orientation estimation. In addition, as a future implementation, an embedded system will be developed with a user-friendly software interface to install the vision system into the Fanuc M10iA/12robot arm and will upgrade the system to a device that can be implemented with any kind of customized robot arms available in the industry.

Abstract:This paper presents results of a series of experiments carried out on models of a car and a truck in a wind tunnel to observe the pressure coefficient variation when the truck was overtaken by the car. However, conventional wind tunnels are not equipped to measure the yaw moment and side force created due to pressure difference created as a result of the interaction of two vehicles and the cross wind. An additional attachment for the wind tunnel was de-signed and built to measure the yawing moment and the side force experienced by the car when the cross wind is ap-plied. The attachment consists of a “top plate” which is independent from the wind tunnel frame and free to rotate. The car model is fixed to the “top plate” the top plate is connected to the base plate via a load measuring shaft which is connected to load cells that enable to measure the yaw moment. The pressure coefficient variation was measured by a series of pressure tapings provided by the circumference of the car. The two models were tested independently in the wind tunnel for their pressure coefficient variation. It was found that the pressure coefficient around the car varies substantially when it is overtaking the truck. It was also observed that when the cross wind is applied the yawing moment and the side force on the car increases with the air speed. The attachment was calibrated prior to the investigation and have been able to obtain consistent results. To relate the observations to real world conditions, fur-ther investigations are necessary.

Abstract:Telecommunications Regulatory Commission of Sri Lanka is the governing body which is responsible for the frequency allocation and monitoring the unauthorized Electromagnetic frequency (EMF) signal transmitting violations. However, in Sri Lanka, currently there is not any proper mechanism to monitor the radiation hazard level and its impact to the people living in the vicinity of mobile communication towers. There are approximately 7000 mobile transmitting towers in Sri Lanka to date and the used frequency range lies between 900MHz to 3GHz for mobile communication. Over the last few decades, many of the health hazard conditions were reported due to the radiation of those harmful EMFs. To cater this problem, a portable real time EMF signal strength measuring system with a radiation hazard level indicator was developed to monitor the EMF level and its impact. The proposed system operates with three intermediate frequency bands (i.e.900MHz, 1800 MHz and 2400MHz) and it’s capable of measuring the power density and the radiation hazard level at that particular point which is being measured. Moreover, the corresponding radiation hazard level is indicated with reference to the standard power density levels published by the International Commission on Non-Ionizing Ra-diation Protection (ICNIRP*). The system works with the overall accuracy of 88% in terms of identifying the power densities and its corresponding radiation hazard levels.

Abstract:Energy preservation is one of the key components in developing eco-friendly machines. In industry, the majority of machines lose a considerable amount of energy through mechanical vibrations. However, the wasted energy through vibration can be utilized as a renewable energy source to compensate for the overall energy loss. The research work presented in this paper discusses the ability to design a linear power generator utilizing Nd Fe-B magnets, which can generate energy through mechanical vibrations. A pilot model was developed and simulated to understand the efficiency and limitation. The results showed that the model could reduce 14% rotor bulk with a marginal impact on the current generation.

Abstract:Ease of use is one of the main criteria that customers consider when making a purchase decision. To provide a pleasant experience to the customers, offering products or services consisting of advanced features and functions is no longer enough, due to the existing competition in the global market. In reality, the ease of use of any product is influenced by the conditions of the product and the familiarity of the user. This study examines the influence of the familiarity and the product conditions on the ease of use of a product. This only explains how the conditions of the product and the fa-miliarity of the user, influence on the ease of use of a product when the usage hours of a product increases. A case study would be conducted to validate the results. The results of this study indicate that in the case where both the product conditions and the familiarity has been varied, the ease of use of the product has been increased from 0.229 to 0.380 gradually within the 10 weeks period. Through these results valuable guidance could be obtained by the manufacturers to identify how the ease of use level of a product deviates from the standard level when the usage hours of the product would increase.

Abstract:This paper analyzes the reliability of low voltage (LV) distribution system of the Sri Lankan power system. Perfor-mance of LV distribution systems where mainly domestic consumers depend on the individual components of the system. Failure rates of elements of the system are calculated based on the historical data of the LV distribution sys-tem in a semi-urban area. Load point reliability indices are calculated using the analytical method. Consumer-oriented reliability parameters and energy not served, and its cost are determined. As a method of improvement of reliability, inclusion of fuses to the lateral feeders of the main feeder is proposed. Load point reliability indices, consum-er-oriented reliability indices, and energy not served are calculated for the distribution system with fuses in lateral feeders. The results are compared with the reliability indices of the present system and analyzed.

Abstract:Teaching and learning-related activities have embraced digital technology especially, with the current global pandemic restrictions pervaded during the last two years. On the other hand, most of the academic and professional presentations are conducted using online platforms. But the presenter-audience interaction is hindered to a certain extent in an online case in contrary to face-to-face where real-time writing is beneficial when sketching is involved. The use of digital pens and pads is a solution for such instances, though the cost of acquiring such hardware is high. Economical solutions are essential as affordability is concerned. In this study, a real-time user-friendly, innovative drawing system is developed to address the issues related to the problems confronted with online presentations. This paper presents the development of an algorithm using Hand Landmark Detection, which replaces chalks, markers and regular ballpoint pens used in conventional communication and presentation, with online platforms. The proposed application in this study is acquired by Python and OpenCV libraries. The letters or the sketches drawn in the air were taken straight to the computer screen by this algorithm. The proposed algorithm continuously identifies the Hand Landmark using the images fed by the web camera, and text or drawing patterns are displayed on the screen according to the movements made by Hand Landmark on the image space. The developed user interface is also user-friendly. Hence the communication of letters and sketches were enabled. Although the concept has been developed and tested, with further research the versatility and accuracy of communication can be enhanced.