Publications
During my undergraduate studies, I have done several mechatronics projects related to the development of robotics systems and MEMS sensors. I was really passionate about my researches and with the guidance of my supervisor Prof.Ranjith Amarasignhe I was able to publish conference papers at two IEEE international conferences and a brief introduction about research projects given here with paper links.
01
Design and Analysis of an Autonomously Guided Vehicle to Minimize the Impact of Covid-19
Abstract-In this paper, the design process of an Automated Guided Vehicle (AGV) is presented, which is intended to be used inside a hospital environment as a multitasking robotic platform. Other than logistics, the system can be used for remote patient monitoring. The AGV will be used as a mobile platform for a mobile manipulator system. A differential drive wheel configuration is used for the vehicle, considering the simplicity of control. The kinematic model of differential drive configuration was used along with the dynamic model, AGV design parameters, and maximum allowable traction forces to simulate AGV motion in the MATLAB Simulink environment. The suggested navigation method-magnetic line following-is robust and accurate compared to other line tracking methods.
02
Design and Analysis of Hybrid Robotic Mechanisms Using SCARA and RCM Mechanisms
Abstract-Serial and parallel are the two types of robotic mechanisms. Since parallel mechanisms have more rigidity and accuracy compared to the serial mechanisms, they are used in many instances. Different types of approaches have been taken to derive new parallel mechanisms using a serial mechanism. Selective Compliance Assembly Robot Arm (SCARA) have used to generate parallel mechanisms like double SCARA and SCARA-Tau. Remote Center Motion (RCM) mechanisms are also widely used in the literature. The combination of the SCARA and RCM mechanisms can generate new mechanisms which have more advantages compared to the single mechanism. In this paper these types of hybrid configurations are discussed. The first design is derived using the concepts of double SCARA and SCARA-Tau. The second design is derived by doing some improvement to the first design by adding a virtual center mechanism. The third design has the concept of the RCM mechanism. All three designs are discussed with their advantages and disadvantages along with the mathematical models and their controlling capabilities.
03
Design and Simulation of a 4-DoF Vibratory Gyroscope
Abstract-In this paper, design and simulation of a Multi DoF (Degree of Freedom) Vibratory Gyroscope is presented. Most of the available gyroscopes are vibratory gyroscopes due to their design and fabrication simplicity. But the performance of these devices is highly sensitive to device operating conditions, fabrication imperfections, and environmental effects. As a solution to this, Multi DoF vibratory gyroscopes have been introduced. The Multi DoF system proposed here consists of 2 DoF drive and sense mode vibrations. During the design procedure of the system, structural parameters are optimized to obtain a constant amplitude flat operational frequency region with a wider bandwidth. In addition to that Dynamic Amplification increases the sensitivity. Drive mode forced vibration is actuated electrostatically and suspension structure was chosen to minimize the quadrature error. The device uses capacitive sensing to measure angular velocity. Further, SOI(Silicon on Insulator) based fabrication process is proposed to fabricate the 4 DoF vibratory gyroscope.
04
MDPI - Micromachines
Abstract-Multiple robots are used in robotic applications to achieve tasks that are impossible to perform as individual robotic modules. At the microscale/nanoscale, controlling multiple robots is difficult due to the limitations of fabrication technologies and the availability of on-board controllers. This highlights the requirement of different approaches compared to macro systems for a group of microrobotic systems. Current microrobotic systems have the capability to form different configurations, either as a collectively actuated swarm or a selectively actuated group of agents. Magnetic, acoustic, electric, optical, and hybrid methods are reviewed under collective formation methods, and surface anchoring, heterogeneous design, and non-uniform control input are significant in the selective formation of microrobotic systems. In addition, actuation principles play an important role in designing microrobotic systems with multiple microrobots, and the various control systems are also reviewed because they affect the development of such systems at the microscale. Reconfigurability, self-adaptable motion, and enhanced imaging due to the aggregation of modules have shown potential applications specifically in the biomedical sector. This review presents the current state of shape formation using microrobots with regard to forming techniques, actuation principles, and control systems. Finally, the future developments of these systems are presented.
05
Nature consists of numerous solutions to overcome challenges in designing artificial systems. Various actuation mechanisms have been implemented in microrobots to mimic the motion of microorganisms. Such bio-inspired designs have contributed immensely to microscale developments. Among the actuation mechanisms, magnetic actuation is widely used in bio-inspired microrobotic systems and related propulsion mechanisms used by microrobots to navigate inside a magnetic field and are presented in this review. In addition, the considered robots are in microscale, and they can swim inside a fluidic environment with a low Reynolds number. In relation to microrobotics, mimicry of bacteria flagella, sperm flagella, cilia, and fish are significant. Due to the fact that these biological matters consist of different propulsion mechanisms, the effect of various parameters was investigated in the last decade and the review presents a summary that enhances understanding of the working principle of propulsion mechanisms. In addition, the effect of different parameters on the various speeds of the existing microrobots was analyzed to identify their trends. So, the swimming speeds of the microrobots show an upward trend with increasing body length, frequency, magnetic flux density, and helix angle. Microfabrication techniques play a significant role in the microscale because the device designs are highly dependent on the availability of the techniques. The presented microrobots were manufactured by 3D/4D photolithography and rapid prototyping techniques. Proper materials enable effective fabrication of microrobots using the mentioned techniques. Therefore, magnetically active material types, matrix materials, biocompatible and biodegradable materials are presented in this study. Utilizing biocompatible and biodegradable materials avoids adverse effects to the organs that could occur otherwise. In addition, magnetic field generation is significant for the propulsion of such microrobots. We conclude the review with an overview of the biomimicry of microrobots and magnetically actuated robot propulsion.
MDPI - Applied Sciences
06
Abstract-This paper discusses an active droplet generation system, and the presented droplet generator successfully performs droplet generation using two fluid phases: continuous phase fluid and dispersed phase fluid. The performance of an active droplet generation system is analysed based on the droplet morphology using vision sensing and digital image processing. The proposed system in the study includes a droplet generator, camera module with image pre-processing and identification algorithm, and controller and control algorithm with a workstation computer. The overall system is able to control, sense, and analyse the generation of droplets. The main controller consists of a microcontroller, motor controller, voltage regulator, and power supply. Among the morphological features of droplets, the diameter is extracted from the images to observe the system performance. The MATLAB-based image processing algorithm consists of image acquisition, image enhancement, droplet identification, feature extraction, and analysis. RGB band filtering, thresholding, and opening are used in image pre-processing. After the image enhancement, droplet identification is performed by tracing the boundary of the droplets. The average droplet diameter varied from ~3.05 mm to ~4.04 mm in the experiments, and the average droplet diameter decrement presented a relationship of a second-order polynomial with the droplet generation time.