Mohammadreza Asghari Oskoei

• PhD
• Fellow at University of Essex

Biomechanical analyses recognize the role of cognitive loads in postural stability by measuring body sway related parameters. However, the simultaneous investigation of the neural and motor behavior during control of the posture is limited. The present study investigated the effects of cognitive load addition on postural control and status of topog...

Maintenance of balance is provided by using different joint strategies regarding the perturbation conditions. Performance of the joint strategies can be assessed by calculation of their kinematic-based features. The aim of this study was to identify the most effective stability features of the dominant role-playing strategy while standing on an uns...

In neural networks, simultaneous determination of the optimum structure and weights is a challenge. This paper proposes a combination of teaching-learning based optimization (TLBO) algorithm and a constructive algorithm (CA) to cope with the challenge. In literature, TLBO is used to choose proper weights, while CA is adopted to construct different...

Social networks have already grown dramatically in various scientific fields. The fields consist of network analysis have interested many researchers to studying network structures. Community-based structure is one of the most important characteristics of complex networks and is a basic concept in the discovery and understanding of networks. In the...

Today, a large number of people all around the world are affected or threatened by different kinds of sleep disorders, especially sleep apnea syndrome (SAS). Since EEG activities during sleep exhibit physiological and pathological situation of the brain, analyzing the oscillations during various sleep stages are of fundamental importance for the as...

Balance is essential for human daily activities. Standing on an unstable platform requires continuous effort of the neuro-musculoskeletal system. Cognitive interference and support surface perturbation may cause loss of balance. The aim of this study is to evaluate the ability of stability provision of individuals while standing in different levels...

Indoor position estimation is essential for navigation; however, it is a challenging task mainly due to the indoor environments’ (a) high noise to signal ratio and (b) low sampling rate and (c) sudden changes to the environments. This paper uses a hybrid filter algorithm for the indoor positioning system for robot navigation integrating Particle Fi...

With the developments and popularity of autonomous systems such as mobile robots, obstacle avoidance has become more and more important as it is one of the most important safety features of autonomous navigation. The moving objects, e.g. Autonomous Mobile Robots, are assumed safe and controllable, particularly in dense urban areas, as long as they...

This paper proposes an adaptive Kalman filter (AKF) to improve the performance of a vision-based human machine interface (HMI) applied to a video game. The HMI identifies head gestures and decodes them into corresponding commands. Face detection and feature tracking algorithms are used to detect optical flow produced by head gestures. Such approach...

This paper presents a novel method of sonar vision, called side sonar vision (SSV), to navigate mobile robots in a known environment. It adopts Omni-directional images and divides surrounding sonar vision into three parts: front, right and left sides. These sides are under continuous scrutiny of individual agents. SSV analyses data of each side, se...

The paper investigates how multi-finger myoelectric signals could be used to control a virtual robotic prosthetic hand created by using robot operating system (ROS). Both off-line and online experiment phases are conducted by using ten electrodes and performing eight selected multi-finger motions on four healthy subjects. Classification accuracy an...

For many multi-robot tasks such as surveillance, environmental monitoring, target tracking, search and rescue missions, accurate multi-robot localization is vital. We introduce a novel scheme called Leader-lobar Localization (LlL). The proposed scheme allows to formulate multi-robot cooperative localization under communication failures as a jointly...

In this paper, we present an omnidirectional vision-based navigation system that includes three approaches: obstacle avoidance based on sonar vision, direction estimation based on sonar vision and confection method of obstacle avoidance and direction estimation. This paper peruses effects of the mirror in omnidirectional vision applied to mobile ro...

Robot motion planning has always been one of the fundamental issues in robotic area. In this paper three motion planning algorithms, A*, Rapidly Exploring Random tree (RRT) and RRT*, are simulated and compared. A* algorithm is a well-known method in motion planning problems which can find the optimum path between two point in a finite time. In cont...

Knapsack problem, is one the most important issues in decision-making and optimization problems, especially in which time and investment has a great importance rate. Genetic Algorithm (GA) and Particle Swarm Optimization algorithm (PSO) can be mentioned as a solution to this problem. GA is one of evolutionary algorithms, that in each of all possibl...

This paper presents a sonar vision algorithm applied to omnidirectional vision. It provides autonomous navigation for a mobile robot in an unknown environment. It uses omnidirectional images without any prior calibration and detects static and dynamic obstacles. It estimates the most intended path based on visual sonar beams in front of the robot....

Robot navigation is challenging for mobile robots technology in environments with maps. Since finding an optimal path for the agent is complicated and time consuming, path planning in robot navigation is an axial issue. The objective of this paper is to find a reasonable relation between parameters used in the path planning algorithm in a plat...

The goal of our research is to develop socially acceptable behavior for domestic robots in a setting where a user and the robot are sharing the same physical space and interact with each other in close proximity. Specifically, our research focuses on approach distances and directions in the context of a robot handing over an object to a user. Our p...

Genetic algorithm is applicable to a wide range of constraint satisfaction problems such as n-queens problem. In the absence of specialized solution for a particular problem, genetic algorithm would be efficient. But holism and random choices cause problem for genetic algorithm in searching large state spaces. So, the efficiency of this algorithm w...

Myoelectric signal is known as an alternative human-machine interface (HMI) for people with motor disability in dealing with assisting robots and rehabilitation devices. This chapter examines a myoelectric HMI in real-time application and compares its performance with traditional tools. It also studies the manifestation of fatigue in long-term musc...

The demographic trend is towards ageing in our society and the number of people with physical impairments and disabilities will increase dramatically in the future. It is necessary to deliver advanced healthcare and services to these people so that they can live independently and stay well at home throughout their lifespan. This paper presents a mu...

Our society is moving towards an ageing society and the number of population with physical impairments and disabilities will increase dramatically. It is necessary to provide mobility support to these people so that they can live independently at home and integrated into the society. This paper presents a ROS (Robot Operating System) based multi-se...

This paper proposes a feature-channel subset selection method for obtaining an optimal subset of features and channels of myoelectric human-machine interface applied to classify upper limb's motions using multi-channel myoelectric signals. It employs a multi-objective genetic algorithm as a search strategy and either data separability index or clas...

A long-term Human-Robot Proxemic (HRP) study was performed using a newly developed Autonomous Proxemic System (APS) for a robot to measure and control the approach distances to the human participants. The main findings were that most HRP adaptation occurred in the first two interaction sessions, and for the remaining four weeks, approach distance p...

Myoelectric signal is known as an alternative human-machine interface (HMI) for people with motor disability in dealing with assisting robots and rehabilitation devices. This chapter examines a myoelectric HMI in real-time application and compares its performance with traditional tools. It also studies the manifestation of fatigue in long-term musc...

This manuscript is a review over the published articles on edge detection. At first, it provides theoretical background, and then reviews wide range of methods of edge detection in different categorizes. The review also studies the relationship between categories, and presents evaluations regarding to their application, performance, and implementat...

This paper presents a vision based human machine interface (HMI) for the Xbox. It applies feature tracking algorithms to recognize user's head gestures and translates them into commands for the game. The pyramidal implementation of Lucas Kanade feature tracking is used to trace the optical flows in a sequence of frames. The experimental results sho...

Myoelectric signal is known as an alternative human-machine interface (HMI) for people with motor disability in dealing with assisting robots and rehabilitation devices. This chapter examines a myoelectric HMI in real-time application and compares its performance with traditional tools. It also studies the manifestation of fatigue in long-term musc...

This paper proposes adaptive schemes for myoelectric based human-machine interface (HMI) applied to a video game. Adaptive schemes modify the classification criteria to keep a stable performance in long-term operations. Online support vector machine (SVM) is used as the core of classification to facilitate incremental training during run-time. Supe...

This paper evaluates supervised and unsupervised adaptive schemes applied to online support vector machine (SVM) that classifies BCI data. Online SVM processes fresh samples as they come and update existing support vectors without referring to pervious samples. It is shown that the performance of online SVM is similar to that of the standard SVM, a...

This paper proposes a myoelectric-based virtual joystick to manipulate an electric powered wheelchair for people with severe motor disabilities. It is built on pattern recognition-based myoelectric control that discriminates muscular activities using forearmpsilas surface myoelectric signals. The core of the system is a support vector machine based...

This paper proposes and evaluates the application of support vector machine (SVM) to classify upper limb motions using myoelectric signals. It explores the optimum configuration of SVM-based myoelectric control, by suggesting an advantageous data segmentation technique, feature set, model selection approach for SVM, and postprocessing methods. This...

This paper investigates manifestation of fatigue in myoelectric signals during dynamic contractions produced whilst playing PC games. The hand's myoelectric signals were collected in 26 independent sessions with 10 subjects. Two methods, spectral analysis and time-scale analysis, were applied to compute signal frequency and least-square linear regr...

This paper presents a novel support vector machine (SVM) approach to upper limb motion classification using myoelectric signals. The main purpose of this paper is to compare SVM-based classifiers with LDA and MLP. SVM demonstrates exceptional classification accuracy and results in a robust way of limb motion classification with low computational co...

The goal of Human-Computer Interface (HCI)) (Human-Robot interface HRI) research is to provide humans with a new communication channel that allows translating Human's will states via a computer into application specific actions. This paper presents a novel hands-free control system for controlling a virtual wheelchair, which is based on Forehead Mu...

The development of an advanced human–machine interface has always been an interesting research topic in the field of rehabilitation, in which biomedical signals, such as myoelectric signals, have a key role to play. Myoelectric control is an advanced technique concerned with the detection, processing, classification, and application of myoelectric...

This paper presents an ongoing investigation to select optimal subset of features from set of well-known myoelectric signals (MES) features in time and frequency domains. Four channel of myoelectric signal from upper limb muscles are used in this paper to classify six distinctive activities. Cascaded genetic algorithm (GA) has been adopted as the s...