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Since recently, UAVs (Unmanned Aerial Vehicles) have increasingly been recognized as a reliable, and effective means of aerial surveillance. Deployment of UAVs in disaster management for aerial surveillance and real-time video feed, when land access is cut off, is one of the most prominent applications. The ability of small, lightweight UAVs in aerial access and gathering data, in areas that are insecure...
Forecasting volatility in the stock market is an important research topic that has been immensely reviewed over the years. However, in Sri Lankan context this research topic is studied by only few researchers and they did not incorporate the day of the week effect in their studies. Therefore, this study examines the impact of the day of the week effect on All Share Price Index (ASPI) of Colombo Stock...
Pitch and airspeed responses of a medium scale UAV were identified using the prediction error method. Data collection was conducted with an active closed loop autopilot control system. A naive SISO open loop transfer function was estimated using the parametric direct approach. Since its predictability was not significant, better estimators were developed using MISO parametric direct, and SISO parametric...
A new trajectory planning method for generating bounded and continuous jerk trajectories in joint space has been developed and tested. In manipulator trajectory planning, reduced jerk trajectories are desired for path tracking and vibration suppression. The proposed interpolation algorithm in this research generates a spline, composed with 5th-order, 3rdorder and 5th-order polynomial segments (5-3-5...
In this paper a transformerless voltage source sine wave inverter is proposed. A previously developed tri-state boost converter is utilized for the stepping up operation. In this topology the dynamic response of the inverter is increased, by avoiding the right hand plane zero in the converter's small-signal control-to-output transfer function when operating in the continuous conduction mode. The reference...
This paper presents modelling, simulation and implementation of a quadrotor Unmanned Arial Vehicle (UAV) Focus of this work is to gain in-depth understanding of quadrotor dynamics to develop a simulator and a laboratory platform to facilitate future development of control algorithms, automatic navigation systems, and trajectory planning for quadrotors. Quadrotor dynamics is modeled using Newton-Euler...
Tunable laser system requires high resolution and accuracy in position of the wave selective optical element, which can be attained through the use of stepper motor. This paper focuses on the stepper motor controller, with the feedback to improve the accuracy and the microstepping technique to improve the resolution. Sine cosine and trapezoidal current controlling techniques for the micro stepping...
This paper introduces techniques for designing and implementing remotely controllable outdoor robots with the ability to localize itself while traversing in hazardous environments. The robot platform designed is a semi-autonomous tiller modified as required by the application. Localization based on wireless sensor network which has been a research interest of is addressed here with the use of Zigbee...
The short-term electricity demand forecasting has become one of the major research area in power system engineering. By combining the smart metering to the short-term demand forecasting techniques, new features can be added to save on demand and electricity bill. This paper illustrates the methodology used to forecast electricity demand over short period of time which can be used with smart meters...
One of the most challenging problems of field robots is self-localization, which involves incremental update of position while in motion. Though wheel based odometry is cheaper to implement its accuracy degrades when wheels slip. In this paper performance of low-cost visual odometry approach is experimented as a feasibility test for field robot localization. We have used a downward-facing camera and...
Position estimation using wheel odometric systems tends to give rather poor performances for an outdoor four-wheel skid steered mobile robot. Therefore autonomous control of these vehicles is extremely challenging in outdoor environments. This paper describes an outdoor localization system based on visual odometry for skid steered vehicle using forward faced camera and a downward faced camera. Optical...
In this paper we first analyze the effects of least square based parameter estimation for a autoregressive stochastic model of inertial sensor errors. We then proceed to develop the recursive least squares (RLS) estimation of the autoregressive model parameters and also discuss a fast update method for recursive least square estimation to reduce the computation complexity. This reduction leads to...
This paper analyzes the performance of an Extended Kalman Filter (EKF) based attitude estimator for a Quad Rotor Unmanned Aerial Vehicle (QRUAV). A non-linear dynamic model of the QRUAV, simulated in Matlab was complemented with an EKF based attitude estimator. The estimator fuses measurements obtained from simulated accelerometers and gyroscopes onboard the QRUAV. It is then shown that this estimator...
The determination of the motor and battery specification is one of the major challenges in the electric vehicle designs, specially considering the different kinds of requirements and specifications in different designs. This paper discusses about a method of simulating a vehicle in given terrains and driver models for extracting the torque, power and battery usage; and hence get the most optimized...
This paper presents a development of a holonomic mobile robot with remote operation capability. Most of the currently available holonomic mobile robots find problems in field applications because they has not been adopted to field environment.To address those problems we have develop a holonomic platform with a capability of carrying 30 kg payload. This platform use normal car type wheels and a complex...
The Axial Flux BLDC motors are relatively new, specially at higher power ratings over 10 kW. Therefore the designers face a lot of difficulties in designing and optimizing the motor for a given application. This paper presents a new method to optimize the performance in speed, torque, torque stability, power output, power density and motor dimensions in view of the cost and reliability for a given...
Standard edge detectors such as Canny edge detector use a local gradient operator to find the ridges in digital images. In this study we show that peer groups and simple variance calculations can be used to improve the performance of gradient operators. Some of the pixels near the threshold are weaker edge pixels of the objects in the image and others are unimportant edges created by unevenness of...
The primary goal of this paper is to provide resources and some ideas for undergraduate research projects and class projects suitable for mathematics, science, and engineering students. We also include a brief discussion of benefits of research projects to Engineering undergraduate education and attempt to identify the properties of research projects that are suitable for undergraduate students.
Tracking of moving objects in a video stream captured from a camera is a very important step in computer vision based applications. This paper provides a novel framework for tracking moving objects in a closed environment using a composite array of inexpensive, off the shelf cameras.
The optimum distribution of treated pipe-borne water is a critical requirement in countries which have a deficit production in comparison with the demand. However, in 3rd world countries, it is not feasible to design the entire water distribution network as a whole, to enable near-optimized delivery, due to economic constraints. The current practice in such countries is to operate the nodes of the...
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