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sensor-fusion
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3-point RANSAC for fast vision based rotation estimation using GPU technology
, Article IEEE International Conference on Multisensor Fusion and Integration for Intelligent Systems9 February 2017 ; 2017 , Pages 212-217 ; 9781467397087 (ISBN) ; Manzuri, M. T ; Marjovi, A ; Karimian, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2017
Abstract
In many sensor fusion algorithms, the vision based RANdom Sample Consensus (RANSAC) method is used for estimating motion parameters for autonomous robots. Usually such algorithms estimate both translation and rotation parameters together which makes them inefficient solutions for merely rotation estimation purposes. This paper presents a novel 3-point RANSAC algorithm for estimating only the rotation parameters between two camera frames which can be utilized as a high rate source of information for a camera-IMU sensor fusion system. The main advantage of our proposed approach is that it performs less computations and requires fewer iterations for achieving the best result. Despite many...
Agent Base Control of a Robotic Swarm with Sensor Noise Effects
, M.Sc. Thesis Sharif University of Technology ; Vossoughi, Gholamreza (Supervisor)
Abstract
The main objective of this project is to investigate modeling for a robotic swarm with suitable sensors and to analyze effect of sensory noise on the control and unity of the swarm. This project is an extension of analytical study done by S. Etemadi, A. Alasty and G. Vossoughi in Sharif University of technology. The flocking frame assumed to have a leader robot that controls over all behavior of the swarm made of agents’ robots with limited equipments and low intelligence that only obey some basic attraction and repulsion laws that will be explained. As an initial step of the analysis, we investigate proper physical model, sensors and navigation systems suitable to the model. Next, the...
MEMS gyro bias estimation in accelerated motions using sensor fusion of camera and angular-rate gyroscope
, Article IEEE Transactions on Vehicular Technology ; Volume 69, Issue 4 , April , 2020 , Pages 3841-3851 ; Manzuri, M. T ; Kamran, D ; Karimian, M ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Although the accuracy of MEMS gyroscopes has been extremely improved, in some aspects, such as stability of bias, they still suffer from some big error sources, like run-to-run bias, which determines the sensor price but is not negligible even inexpensive sensors. Due to the fact that run-to-run bias is a kind of stochastic parameter, it has to be measured by utilizing online methods. Utilizing a novel, fast and efficient vision-based rotation estimation algorithm for ground vehicles, we have developed a visual gyroscope that is used in our sensor fusion system, in order to estimate run-to-run bias of the MEMS gyroscope, accurately. Comparing with similar approaches that use GPS, odometer,...
Usage and Improvement of Bundle Adjustment Method for Determining Image Orientation
, M.Sc. Thesis Sharif University of Technology ; Manzouri, Mohammad Taghi (Supervisor)
Abstract
Pose and motion estimation using a set of images is a common application in photogrammetry and one of the most popular methods in doing so is Bundle adjustment. This method later got adapted to the field of computer vision and is mainly used to reconstruct a 3d scene while also estimating pose and motion of the camera. There are a variety of other methods used to estimate pose and motion. Most non-visual methods like using inertial navigation system and GPS suffer from shortcomings like accumulative error, availability problems or low accuracy. While most vision based one are computationally expensive. In this thesis two methods are proposed to increase accuracy and efficiency of one variant...
Calculating the Angle of Camera Using Optimal Filter
, M.Sc. Thesis Sharif University of Technology ; Manzuri, Mohammad Taghi (Supervisor) ; Jafari, Mahdi (Co-Advisor)
Abstract
Today with increasing advancement of robotic technology, we witness the increment of robots role in humans’ life. One of the issues always present for robots is routing which may require locating their position. Most of these robots make use of sensors like gyroscope, accelerometer and GPS to estimate their position. But each of these sensors has their own short comings such as drift or being unavailable in certain environments. Fusion of inertial and vision sensor’s data can be used to reduce the impact of these errors. Considering the time consumption of image processing and accumulating error of inertial sensor, this combination can be very useful. This approach is also used in...
Improvement of Dynamic Modeling and Control of Single-axis Two wheeled Vehicle
, M.Sc. Thesis Sharif University of Technology ; Vosoughi, Gholamreza (Supervisor)
Abstract
In the recnt decades, traffics and airpolution are the most impoetant concerns of researchers in the field of city transportation. One of the most successful ways to overcome these poblems is to ustilize two-wheeled, one axis balancing vehicles. These vehicles occupies a small sapace, consumes less energy and its considerable maneuverability, makes it the best option to reform in-city transportation system. The newly introduced model of these robots incorporates a passenger cabin and a strick to control its movement. Unfortunately, in all of the recent studies, robots dynamics and controller system are base on optimistic hypothesis, which is no slippage between ground and wheels. Even in the...
Robust Orientation Estimation Using Imu and Online Machine Learning Based Calibration in the Presence of Distortions
, M.Sc. Thesis Sharif University of Technology ; Khodaygan, Saeed (Supervisor)
Abstract
In this project an optimized and robust orientation estimation method using IMU and magnetic sensors is presented. Magnetic distortion effects in orientation estimation is also one of the main purposes. Proposed sensor fusion algorithm is based on a complementary filter which provides a quaternion estimation as the algebraic solution of a system from inertial/magnetic observations. To develop the basic sensor fusion algorithm some procedures including a simple calculation to deal better with non-gravitational accelerations, decrease the effect of magnetometer in the presence of distortions and online gyroscope bias estimation is added. Also, a method for classification the different types of...
Improving Attitude of a Motion Robotby Fusion of Inertial Gyroscope and Image Rotation
, M.Sc. Thesis Sharif University of Technology ; Manzouri, Mohammad Taghi (Supervisor)
Abstract
Nowadays, the use of MEMS sensors, due to their small size, lightweight and low cost, has been welcomed in systems such as autonomous vehicles. Although the precision of MEMS gyroscopes has been extremely improved, in some aspects, such as stability of bias, they still suffer from some big error sources, like run-to run bias, which determines the sensor price but is not negligible even inexpensive sensors. In addition to the bias, there are a lot of noises in the gyroscope outputs, where ARW is one of the most important ones, which causes failure in real-signals and produces an error in the position and attitude of mobile systems. Due to the fact that run-to-run bias and ARW are stochastic...
Design and implementation of an improved real-time tracking system for navigation surgery by fusion of optical and inertial tracking methods
, Article Applied Mechanics and Materials ; Volume 186 , 2012 , Pages 273-279 ; 16609336 (ISSN) ; 9783037854440 (ISBN) ; Farahmand, F ; Salarieh, H ; Sharif University of Technology
2012
Abstract
The fusion of the optical and inertial tracking systems seems an attractive solution to solve the shadowing problem of the optical tracking systems, and remove the time integration troubles of the inertial sensors. We developed a fusion algorithm for this purpose, based on the Kalman filter, and examined its efficacy to improve the position and orientation data, obtained by each individual system. Experimental results indicated that the proposed fusion algorithm could effectively estimate the 2 seconds missing data of the optical tracker
Cooperative abnormality detection via diffusive molecular communications
, Article IEEE Transactions on Nanobioscience ; Volume 16, Issue 8 , 2017 , Pages 828-842 ; 15361241 (ISSN) ; Jamali, V ; Ghoroghchian, N ; Schober, R ; Nasiri-Kenari, M ; Mehrabi, M ; Sharif University of Technology
Abstract
In this paper, we consider abnormality detection via diffusive molecular communications (MCs) for a network consisting of several sensors and a fusion center (FC). If a sensor detects an abnormality, it injects a number of molecules into the medium which is proportional to its sensing output. Two transmission schemes for releasing molecules into the medium are considered. In the first scheme, each sensor releases a different type of molecule (DTM), whereas in the second scheme, all sensors release the same type of molecule (STM). The molecules released by the sensors propagate through the MC channel and some may reach the FC where the final decision regarding whether or not an abnormality...
Trunk motion system (TMS) using printed body worn sensor (BWS) via data fusion approach
, Article Sensors (Switzerland) ; Volume 17, Issue 1 , 2017 ; 14248220 (ISSN) ; Zobeiri, O ; Moshiri, B ; Narimani, R ; Mehravar, M ; Rashedi, E ; Parnianpour, M ; Sharif University of Technology
MDPI AG
2017
Abstract
Human movement analysis is an important part of biomechanics and rehabilitation, for which many measurement systems are introduced. Among these, wearable devices have substantial biomedical applications, primarily since they can be implemented both in indoor and outdoor applications. In this study, a Trunk Motion System (TMS) using printed Body‐Worn Sensors (BWS) is designed and developed. TMS can measure three‐dimensional (3D) trunk motions, is lightweight, and is a portable and non‐invasive system. After the recognition of sensor locations, twelve BWSs were printed on stretchable clothing with the purpose of measuring the 3D trunk movements. To integrate BWSs data, a neural network data...
An Integrated Active Circulator for Radar Transceivers with Shared Tx/Rx Antenna
, M.Sc. Thesis Sharif University of Technology ; Fotowat Ahmadi, Ali (Supervisor) ; Akbar, Fatemeh (Supervisor)
Abstract
The issue of automation has always been a concern for humans over the years. Replacing humans with machines or intelligent software to perform various tasks can significantly improve the accuracy and speed of those activities. One of the long-standing aspirations of humanity has been the automation of driving. In addition to freeing individuals from the time-consuming task of driving, automating vehicles can also dramatically reduce road accidents. To achieve this goal, vehicles need to be equipped with various sensors such as radar, cameras, lidar, and more. Each of these sensors has its advantages and disadvantages, and as a result, all of them must be used for safe driving. In this...
Towards real-time partially self-calibrating pedestrian navigation with an inertial sensor array
, Article IEEE Sensors Journal ; Volume 20, Issue 12 , 2020 , Pages 6634-6641 ; Salarieh, H ; Alasty, A ; Sharif University of Technology
Institute of Electrical and Electronics Engineers Inc
2020
Abstract
Inspired by algorithms utilized in inertial navigation, an inertial motion capturing algorithm capable of position and heading estimation is introduced. The fusion algorithm is capable of real-time link geometry estimation, which allows for the imposition of biomechanical constraints without a priori knowledge regarding sensor placements. Furthermore, the algorithm estimates gyroscope and accelerometer bias, scaling, and non-orthogonality parameters in real-time. The stationary phases of the links, during which pseudo-measurements such as zero velocity or heading stabilization updates are applied, are detected using optically trained neural networks with buffered accelerometer and gyroscope...