Mary Alatise - Academia.edu (original) (raw)
Papers by Mary Alatise
2022 International Conference on Artificial Intelligence, Big Data, Computing and Data Communication Systems (icABCD)
Supporting mobility is one the major challenges in wireless networks. To support mobility in any ... more Supporting mobility is one the major challenges in wireless networks. To support mobility in any wireless network, the application of an efficient handover control scheme is crucial. In hard handover scenarios in mobile WiMAX networks, a Mobile Station (MS) may experience handover disruptions and handover delays during transmission which could result in connection drops and waste of resources. In order to address some of these potential problems associated with hard handovers, a Relative Signal Strength with Threshold and adaptive Hysteresis and Distance (RSTH-D) scheme is proposed in this paper. This scheme seeks to initiate quick handover so as to reduce handover delays, avoid interruption of transmission and effectively utilise available radio resources. It is shown, through the simulation results obtained, that the proposed scheme has significant performance benefits compared to relative signal strength with hysteresis and threshold schemes. The performance of the various scheme...
The addition to the WiMAX standard through 802.16e has made the standard more flexible and a pote... more The addition to the WiMAX standard through 802.16e has made the standard more flexible and a potential choice as a wireless broadband technology. To support mobility in any wireless scheme, the application of an efficient handover control scheme is crucial. Any inefficiency experienced during data transmission in hard handover in mobile network could cause handover delays with potential connection drops. In order to solve the problem of handover delay, various types of handover scheme have been adopted. This paper proposes the combining of the Relative Signal Strength with Threshold and Hysteresis and Distance (RSTH-D) to initiate handover. Distance is considered as a criterion to initiate fast handover. This scheme seeks to reduce handover delay, which contributes to effective radio resource management. It is shown through the simulation results obtained that the proposed scheme has significant potential performance benefits compared to standard handover schemes.
2017 IEEE AFRICON, 2017
Practically, today most mobile devices, such as robots require to have ability to determine their... more Practically, today most mobile devices, such as robots require to have ability to determine their pose (location and orientation) from low-cost sensors with high accuracy. This paper presents a novel fusion method to determine the pose estimation of an autonomous mobile robot using inertial sensors and a camera. Speeded up robust features (SURF) is used as a visual algorithm to detect natural landmarks (also known as markerless method) from image sequence. SURF is an effective detector and descriptor algorithm which can detect key point features from images regardless of the lighting or different viewing conditions. The inertial sensors used are six degree of freedom (6DOF) which comprises 3-axis of accelerometer and 3-axis of gyroscope. The data from inertial sensor and vision are fused together using Extended Kalman Filter (EKF). The key contribution of this paper is the low-cost, easy deployment and fast computation. The system combines the best of each sensor, more information derived from the camera and the fast response of the inertial sensors. Experimental and simulated results show that this method is fast in computation, reliable and improves accuracy. Root mean square errors (RMSEs) for position and orientation were achieved in the experiments.
Sensors, 2017
Using a single sensor to determine the pose estimation of a device cannot give accurate results. ... more Using a single sensor to determine the pose estimation of a device cannot give accurate results. This paper presents a fusion of an inertial sensor of six degrees of freedom (6-DoF) which comprises the 3-axis of an accelerometer and the 3-axis of a gyroscope, and a vision to determine a low-cost and accurate position for an autonomous mobile robot. For vision, a monocular vision-based object detection algorithm speeded-up robust feature (SURF) and random sample consensus (RANSAC) algorithms were integrated and used to recognize a sample object in several images taken. As against the conventional method that depend on point-tracking, RANSAC uses an iterative method to estimate the parameters of a mathematical model from a set of captured data which contains outliers. With SURF and RANSAC, improved accuracy is certain; this is because of their ability to find interest points (features) under different viewing conditions using a Hessain matrix. This approach is proposed because of its simple implementation, low cost, and improved accuracy. With an extended Kalman filter (EKF), data from inertial sensors and a camera were fused to estimate the position and orientation of the mobile robot. All these sensors were mounted on the mobile robot to obtain an accurate localization. An indoor experiment was carried out to validate and evaluate the performance. Experimental results show that the proposed method is fast in computation, reliable and robust, and can be considered for practical applications. The performance of the experiments was verified by the ground truth data and root mean square errors (RMSEs).
2022 International Conference on Artificial Intelligence, Big Data, Computing and Data Communication Systems (icABCD)
IEEE Access
Autonomous mobile robots are becoming more prominent in recent time because of their relevance an... more Autonomous mobile robots are becoming more prominent in recent time because of their relevance and applications to the world today. Their ability to navigate in an environment without a need for physical or electro-mechanical guidance devices has made it more promising and useful. The use of autonomous mobile robots is emerging in different sectors such as companies, industries, hospital, institutions, agriculture and homes to improve services and daily activities. Due to technology advancement, the demand for mobile robot has increased due to the task they perform and services they render such as carrying heavy objects, monitoring, search and rescue missions, etc. Various studies have been carried out by researchers on the importance of mobile robot, its applications and challenges. This survey paper unravels the current literatures, the challenges mobile robot is being faced with. A comprehensive study on devices/sensors and prevalent sensor fusion techniques developed for tackling issues like localization, estimation and navigation in mobile robot are presented as well in which they are organised according to relevance, strengths and weaknesses. The study therefore gives good direction for further investigation on developing methods to deal with the discrepancies faced with autonomous mobile robot.
2022 International Conference on Artificial Intelligence, Big Data, Computing and Data Communication Systems (icABCD)
Supporting mobility is one the major challenges in wireless networks. To support mobility in any ... more Supporting mobility is one the major challenges in wireless networks. To support mobility in any wireless network, the application of an efficient handover control scheme is crucial. In hard handover scenarios in mobile WiMAX networks, a Mobile Station (MS) may experience handover disruptions and handover delays during transmission which could result in connection drops and waste of resources. In order to address some of these potential problems associated with hard handovers, a Relative Signal Strength with Threshold and adaptive Hysteresis and Distance (RSTH-D) scheme is proposed in this paper. This scheme seeks to initiate quick handover so as to reduce handover delays, avoid interruption of transmission and effectively utilise available radio resources. It is shown, through the simulation results obtained, that the proposed scheme has significant performance benefits compared to relative signal strength with hysteresis and threshold schemes. The performance of the various scheme...
The addition to the WiMAX standard through 802.16e has made the standard more flexible and a pote... more The addition to the WiMAX standard through 802.16e has made the standard more flexible and a potential choice as a wireless broadband technology. To support mobility in any wireless scheme, the application of an efficient handover control scheme is crucial. Any inefficiency experienced during data transmission in hard handover in mobile network could cause handover delays with potential connection drops. In order to solve the problem of handover delay, various types of handover scheme have been adopted. This paper proposes the combining of the Relative Signal Strength with Threshold and Hysteresis and Distance (RSTH-D) to initiate handover. Distance is considered as a criterion to initiate fast handover. This scheme seeks to reduce handover delay, which contributes to effective radio resource management. It is shown through the simulation results obtained that the proposed scheme has significant potential performance benefits compared to standard handover schemes.
2017 IEEE AFRICON, 2017
Practically, today most mobile devices, such as robots require to have ability to determine their... more Practically, today most mobile devices, such as robots require to have ability to determine their pose (location and orientation) from low-cost sensors with high accuracy. This paper presents a novel fusion method to determine the pose estimation of an autonomous mobile robot using inertial sensors and a camera. Speeded up robust features (SURF) is used as a visual algorithm to detect natural landmarks (also known as markerless method) from image sequence. SURF is an effective detector and descriptor algorithm which can detect key point features from images regardless of the lighting or different viewing conditions. The inertial sensors used are six degree of freedom (6DOF) which comprises 3-axis of accelerometer and 3-axis of gyroscope. The data from inertial sensor and vision are fused together using Extended Kalman Filter (EKF). The key contribution of this paper is the low-cost, easy deployment and fast computation. The system combines the best of each sensor, more information derived from the camera and the fast response of the inertial sensors. Experimental and simulated results show that this method is fast in computation, reliable and improves accuracy. Root mean square errors (RMSEs) for position and orientation were achieved in the experiments.
Sensors, 2017
Using a single sensor to determine the pose estimation of a device cannot give accurate results. ... more Using a single sensor to determine the pose estimation of a device cannot give accurate results. This paper presents a fusion of an inertial sensor of six degrees of freedom (6-DoF) which comprises the 3-axis of an accelerometer and the 3-axis of a gyroscope, and a vision to determine a low-cost and accurate position for an autonomous mobile robot. For vision, a monocular vision-based object detection algorithm speeded-up robust feature (SURF) and random sample consensus (RANSAC) algorithms were integrated and used to recognize a sample object in several images taken. As against the conventional method that depend on point-tracking, RANSAC uses an iterative method to estimate the parameters of a mathematical model from a set of captured data which contains outliers. With SURF and RANSAC, improved accuracy is certain; this is because of their ability to find interest points (features) under different viewing conditions using a Hessain matrix. This approach is proposed because of its simple implementation, low cost, and improved accuracy. With an extended Kalman filter (EKF), data from inertial sensors and a camera were fused to estimate the position and orientation of the mobile robot. All these sensors were mounted on the mobile robot to obtain an accurate localization. An indoor experiment was carried out to validate and evaluate the performance. Experimental results show that the proposed method is fast in computation, reliable and robust, and can be considered for practical applications. The performance of the experiments was verified by the ground truth data and root mean square errors (RMSEs).
2022 International Conference on Artificial Intelligence, Big Data, Computing and Data Communication Systems (icABCD)
IEEE Access
Autonomous mobile robots are becoming more prominent in recent time because of their relevance an... more Autonomous mobile robots are becoming more prominent in recent time because of their relevance and applications to the world today. Their ability to navigate in an environment without a need for physical or electro-mechanical guidance devices has made it more promising and useful. The use of autonomous mobile robots is emerging in different sectors such as companies, industries, hospital, institutions, agriculture and homes to improve services and daily activities. Due to technology advancement, the demand for mobile robot has increased due to the task they perform and services they render such as carrying heavy objects, monitoring, search and rescue missions, etc. Various studies have been carried out by researchers on the importance of mobile robot, its applications and challenges. This survey paper unravels the current literatures, the challenges mobile robot is being faced with. A comprehensive study on devices/sensors and prevalent sensor fusion techniques developed for tackling issues like localization, estimation and navigation in mobile robot are presented as well in which they are organised according to relevance, strengths and weaknesses. The study therefore gives good direction for further investigation on developing methods to deal with the discrepancies faced with autonomous mobile robot.