Hamed Shahbazi - Academia.edu (original) (raw)

Papers by Hamed Shahbazi

Research paper thumbnail of Demonstration learning of robotic skills using repeated suggestions learning algorithm

Biologically inspired cognitive architectures, Apr 1, 2017

In this paper a new model of nonlinear dynamical system based on adaptive frequency oscillators f... more In this paper a new model of nonlinear dynamical system based on adaptive frequency oscillators for learning rhythmic signals is implemented by demonstration. This model uses coupled Hopf oscillators to encode and learn any periodic input signal. Learning process is completely implemented in the dynamics of adaptive oscillators. One of the issues in learning in such systems is constant number of oscillators in the feedback loop. In other words, the number of adaptive frequency oscillators is one of the design factors. In this contribution, it is shown that using enough number of oscillators can help the learning process. In this paper, we address this challenge and try to solve it in order to learn the rhythmic movements with greater accuracy, lower error and avoid missing fundamental frequency. To reach this aim, a method for generating drumming patterns is proposed which is able to generate rhythmic and periodic trajectories for a NAO humanoid robot. To do so, a programmable central pattern generator is used which is inspired from animal's neural systems and these programmable central pattern generators are extended to learn patterns with more accuracy for NAO humanoid robots. Successful experiments of demonstration learning are done using simulation and a NAO Real robot.

Research paper thumbnail of Design , manufacturing and test of a wearable device to monitor athlete ' s body movements

In this paper a device based on wearable sensors is introduced to describe quantitative body move... more In this paper a device based on wearable sensors is introduced to describe quantitative body movements in different sports. This device can be an alternative of Image processing techniques. Image processing devices have always been used to describe quantitative body movements, which in addition to being costly, have to be used in specific conditions. The device is built from a number of wireless modules that are easy to use in real-world environments with no limitations. In this method, a quantitative description of movement is made by wireless modules and is performed by the data collected from these modules. In order to analyze the data that was extracted from an athlete's body movements with these wearable sensors, the outputs are simulated in Matlab, and some of its kinematic and kinetic parameters have been studied. Then, at the end of this paper, the quality of movement of a professional athlete and a beginner athlete are compared, and the result is shown. Kinematic and dy...

Research paper thumbnail of Design and Implementation of a Neural Intelligent Controller and a Hybrid PD Controller for Quadrotor

هلاقم تاعلاطا هدیکچ لماک یشهوژپ هلاقم :تفایرد 01 تشهبیدرا 1396 :شریذپ 05 رویرهش 1396 :تیاس رد هئا... more هلاقم تاعلاطا هدیکچ لماک یشهوژپ هلاقم :تفایرد 01 تشهبیدرا 1396 :شریذپ 05 رویرهش 1396 :تیاس رد هئارا 28 رهم 1396 تابر عاونا زا یکی روتورداوک یم هدنرپ یاه هب هک دشاب .تسا هتفرگ رارق ناققحم زا یرایسب هجوت دروم یزاورپ دومع تیلباق و هداس راتخاس لیلد ادیدش کیمانید لیلد هب متسیس نیا یرادیاپ هژیو تیمها زا یطخریغ یا یاهرلرتنک هلاقم نیا رد متسیس نیا یزاسرادیاپ یارب .تسا رادروخرب رلرتنک ،یبیکرت کیسلاک PD هکبش و هیبش و یحارط یبصع یاه هدش یزاس شزومآ ییاناوت اب یبصع هکبش کی یحارط هب ادتبا هلاقم نیا رد .دنا اب ار دوخ یشزومآ هداد هب زاین نودب هکبش نیا .تسا هدش هتخادرپ طخرب یم میظنت ار هکبش بیارض و هداد قیبطت متسیس رلرتنک کی سپس .دنک کیسلاک PD هب هک یبصع هکبش کی زا هدافتسا اب سپس و هدش نایب زلوکین رلگیز شور زا هدافتسا اب تروص آ هب ،هدش هداد شزومآ نیلان یم هتخادرپ رلرتنک نیا یلرتنک یاهرتماراپ میظنت نیا ییاراک نییعت یارب .دوش هیبش ،اهرلرتنک هیبش طیحم رد یزاس بلتم یزاس و تفرگ ماجنا جیاتن یلمع لکش هب هدروآ هیبش لدم کی ،یعقاو متسیس یور اهرلرتنک نیا یزاس هدایپ یارب .تسا هدش اب هک هدش هئارا روتورداوک یارب ...

Research paper thumbnail of Imitation Learning of Complex Behaviors to Humanoid Robots using Evolutionary Optimization of Neural Network of Unit Pattern Generator

In this paper, a system based on neural structures known as central pattern generator is presente... more In this paper, a system based on neural structures known as central pattern generator is presented which enables to acquire the required patterns to move a robot based on a demonstration training. Unit pattern generator can be divided to two subsystems, one is a rhythmic system and the other is a discrete system. The first subsystem is responsible to produce short movements and the second subsystem is responsible to produce rhythmic movements. The special learning algorithm is designed to use these unit pattern generators. Joints and limbs of robot were controlled by Kinect sensor in real time by recognition of the human body skeleton. The work steps were done in this way that the motion sequences of teacher’ body were recorded by Kinect sensor, then transmitted to the computer. These motion sequences teach some nonlinear oscillators then they reproduce motions for humanoid robot. As a result, humanoid body joints imitate the teacher movement in a real time. The main contribution of...

Research paper thumbnail of Developing Imitation Learning to Produce Rhythmic Motion of Drumming in Nao Humanoid Robot Using Superellipses

This paper discussed the development of imitation learning in Nao humanoid robot inspired by cent... more This paper discussed the development of imitation learning in Nao humanoid robot inspired by central pattern generator. Purpose of imitation learning is to enable people to teach new skills to robots via showing examples to them. In sum, the issue studied in this paper was imitation learning for rhythmic actions. Basics of robot learning in this paper included appropriate demonstration techniques, understanding teachers' demonstrations, and an introduction to reinforcement learning. The proposed method was formed based on the evolution of past techniques and superellipses were used to extend the application of imitation learning in drumming. Superellipses, as a wide range of closed geometric curves, are very important for engineers, because they have helpful and precise features in terms of design, programming, and control. The advantage of the proposed method was in the ability to encode learned periodic signals as a limit cycle of superellipses, which influenced louder or lowe...

Research paper thumbnail of Design and implementation of attitude PID controller with fuzzy system to adjust the controller gain values for quadrotor

دییامن هدافتسا لیذ ترابع زا هلاقم نیا هب عاجرا يارب : Please cite this article using: V. Tikani, ... more دییامن هدافتسا لیذ ترابع زا هلاقم نیا هب عاجرا يارب : Please cite this article using: V. Tikani, H. Shahbazi, Design and implementation of attitude PID controller with fuzzy system to adjust the controller gain values for quadrotor, Modares Mechanical Engineering, Vol. 16, No. 9, pp. 19-28, 2016 (in Persian) هدایپ و یحارط هیواز رلرتنک يزاس يا PID هرهب اب میظنت يارب يزاف متسیس زا يریگ هرهب یلرتنک ياه روتورداوک

Research paper thumbnail of Practical implementation of a PID-Model Reference Adaptive Controller for a 2-DOF Camera Gimbal

هلاقم تاعلاطا هدیکچ لماک یشهوژپ هلاقم :تفایرد 06 نیدرورف 1396 :شریذپ 09 ادرخ د 1396 :تیاس رد هئار... more هلاقم تاعلاطا هدیکچ لماک یشهوژپ هلاقم :تفایرد 06 نیدرورف 1396 :شریذپ 09 ادرخ د 1396 :تیاس رد هئارا 06 م دادر 1396 رتماراپ راکدوخ میظنت تهج عجرم لدم یقیبطت لرتنک شور ،هلاقم نیا رد رادیاپ کی رلرتنک یاه یم هئارا نیبرود زاس خساپ هک یوحنب ،دوش یدحاو عجرم لدم خساپ زا فلتخم یسرنیا طیارش تحت متسیس رادیاپ .دیامن یوریپ هک تسا کرحتم هیاپ کی رب لمتشم لابمیگ ای نیبرود زاس راومه تیلباق ،نیبرود هب لاعفریغ ای لاعف لاصتا اب شخرچ لباقم رد ریواصت تیبثت و تکرح یزاس شزرل و اه راد ار وکس یاه د تلاکشم زا یکی . لابمیگ یاه یراجت هب رداق طقف هک تسا نیا رازاب رد دوجوم نیبرود لمح یم دوخ هب صوصخم یاه نیا یور رب یرگید نیبرود رگا و دنشاب لابمیگ یمن ،دوش هتسب اه نیبرود مرج زکرم لحم و یسرنیا توافت لیلد هب لکشم نیا .دننک ظفح ار دوخ هیلوا بسانم درکلمع دنناوت فلتخم یاه .تسا رگیدکی اب ور ،لکشم نیا لح یاتسار رد ،هلاقم نیا رد هدایپ یعقاو متسیس یور رب ونیودرآ درب کمک هب یگنردلاب یرلرتنک ش یلمع یزاس رلرتنک یلمع یزاس هدایپ سپس و هدیدرگ ماجنا یدازآ هجرد ود لابمیگ تخاس و یحارط ادتبا رد .تسا هدش PID یور رب عجرم لدم یقیبطت ع یس...

Research paper thumbnail of Design PID and Fractional-Order PID Controller and Experimental Evaluation of PID Controller Performance for Attitude Control of Quadrotor

The purpose of this paper is to design a fractional order PID (FOPID) controller base on stochast... more The purpose of this paper is to design a fractional order PID (FOPID) controller base on stochastic algorithms for attitude control of quadrotor. The model is based on usage of Fractional calculus in the PID Controllers which can provide novel and higher performance extension for FOPID controllers. Here, the main goal is to design an optimal PID and FOPID controller using stochastic algorithms. Therefor two stochastic algorithms are used for optimal tuning of FOPID parameters. Genetic Algorithm (GA) and Particle Swarm Optimization are compared in minimizing the performance criteria formula which leads to a better performance in controlling of the plant. A quadrotor is installed on an experimental test stand includes of accelerometers, gyroscopes and microcontroller with one and three degrees of freedom to test the performance of PID controller. Kalman filter is used to reduce the noises by combination of accelerometer and gyroscope output. The result of the experiments in the paper ...

Research paper thumbnail of Modeling the Drivers of Eco-Innovation Adoption within Iranian Manufacturing Small and Medium-Sized Enterprises

International Journal of Applied Operational Research - An Open Access Journal, 2017

There are various studies on the eco-innovation in the literature, but there is a scarcity of stu... more There are various studies on the eco-innovation in the literature, but there is a scarcity of studies on the adoption and diffusion within manufacturing small and medium-size enterprises (SMEs). Drivers to adopt eco-innovations by manufacturing SMEs are required to be understood properly and be analyzed regarding the relationships among them. Hence, the purpose of this study is to identify the main drivers of eco-innovation adoption by Iranian manufacturing SMEs from the literature and further model them based on experts’ opinions. We have utilized the valuable opinions of experts to develop a hierarchical model of drivers utilizing Interpretive Structural Modeling approach to demonstrate the contextual interrelationship among these factors. Furthermore, degrees of relationships among the drivers were obtained according to Matrice d'Impacts Croises Multipication Applique ́ an Classment analysis approach. Identification and modeling of eco-innovation drivers is expected to assist...

Research paper thumbnail of Moderating Effects of Demographics on Green Information System Adoption

International Journal of Innovation and Technology Management, 2019

The important role of demographics on technology adoption has been highlighted vastly in the lite... more The important role of demographics on technology adoption has been highlighted vastly in the literature. Therefore, this study aims at investigating the moderating role of managers’ demographics in their decision-making process to adopt Green information system (Green IS) from the lens of norm activation theory. With 175 valid questionnaires hand collected from organizations’ decision-makers, the researchers examined the research model and its related hypotheses utilizing the Partial Least Squares (PLS)–Structural Equation Modeling (SEM). The results showed Green IS attitude together with personal norm to be the most influential factors, followed by environmental attitude. In addition, we found that while awareness of consequences significantly impacted personal norms, its explanatory power on personal norms was higher when it was mediated through ascription of responsibility. Regarding the moderator variables, the model explained better the pro-environmental behavioral intention of...

Research paper thumbnail of Factors Influencing Beliefs Formation towards the Adoption of Social Commerce in SME Travel Agencies

Economics & Sociology, 2018

The purpose of this study is to investigate the factors that influence beliefs formation towards ... more The purpose of this study is to investigate the factors that influence beliefs formation towards the adoption of social commerce in SME travel agencies. Accordingly, a distal-proximal model is developed to study CEOs' beliefs towards the usefulness of social commerce. Data were collected through a questionnaire survey of travel agencies' CEOs in Isfahan, Iran. With 180 collected data from respondents, the Partial Least Squares-Structural Equation Modeling approach was taken to assess both measurement and structural models of the study. The results revealed that CEOs' innovativeness and attitude towards IT as individual factors, and organizational resources as institutional factor were significantly explained beliefs formation of respondents towards the usefulness of social commerce. However, it was found that the influences of CEOs' IT knowledge, subjective norms (professional peers, employees) and firm size on perceived usefulness were found insignificant. Implications of the study are further discussed.

Research paper thumbnail of The moderating effect of experience on the intention to adopt mobile social network sites for pedagogical purposes: An extension of the technology acceptance model

Education and Information Technologies, 2018

With numerous benefits of utilising mobile social network sites (SNSs) for learning purposes, lim... more With numerous benefits of utilising mobile social network sites (SNSs) for learning purposes, limited studies have been conducted to determine the factors that influence the adoption of mobile SNSs in facilitating learning. Accordingly, the main purpose of this study is to explore the determinants of students' behavioural intention to use mobile SNSs for their pedagogical purposes by utilising an extended version of Technology Acceptance Model. Furthermore, the moderating effect of users' experience on their behavioural intention was investigated. Using a structured questionnaire, data were collected from 600 students from top-five public universities of Malaysia. The results revealed perceived task-technology fit as the great predictor of users' intention and perceived usefulness. Although the moderating impact of students'

Research paper thumbnail of Demonstration learning of robotic skills using repeated suggestions learning algorithm

Biologically Inspired Cognitive Architectures, 2017

In this paper a new model of nonlinear dynamical system based on adaptive frequency oscillators f... more In this paper a new model of nonlinear dynamical system based on adaptive frequency oscillators for learning rhythmic signals is implemented by demonstration. This model uses coupled Hopf oscillators to encode and learn any periodic input signal. Learning process is completely implemented in the dynamics of adaptive oscillators. One of the issues in learning in such systems is constant number of oscillators in the feedback loop. In other words, the number of adaptive frequency oscillators is one of the design factors. In this contribution, it is shown that using enough number of oscillators can help the learning process. In this paper, we address this challenge and try to solve it in order to learn the rhythmic movements with greater accuracy, lower error and avoid missing fundamental frequency. To reach this aim, a method for generating drumming patterns is proposed which is able to generate rhythmic and periodic trajectories for a NAO humanoid robot. To do so, a programmable central pattern generator is used which is inspired from animal's neural systems and these programmable central pattern generators are extended to learn patterns with more accuracy for NAO humanoid robots. Successful experiments of demonstration learning are done using simulation and a NAO Real robot.

Research paper thumbnail of Mechatronic design and construction of a five axes satellite simulator

2016 4th International Conference on Robotics and Mechatronics (ICROM), 2016

This article describes the construction of a five spacecraft flight simulator based on an air bea... more This article describes the construction of a five spacecraft flight simulator based on an air bearing system, which was designed and instrumented in university of Isfahan laboratory to evaluate and to perform research in the field of Attitude Determination and Control Systems for spacecraft. This simulator is modeled in Autodesk-Inventor software package to design the simulator component precisely. The hardware and software components of the testbed are detailed in this article. the constraints for the construction and final realization of this attitude simulator testbed are depicted. It describes all modifications needed to reconfigure the simulator system testbed.

Research paper thumbnail of A New Approach for Scoring Relevant Documents by Applying a Farsi Stemming Method in Persian Web Search Engines

... Search Engines Hamed Shahbazi, Alireza Mokhtaripour, Mohammad Dalvi, and Behrouz Tork Ladani ... more ... Search Engines Hamed Shahbazi, Alireza Mokhtaripour, Mohammad Dalvi, and Behrouz Tork Ladani Department of computer engineering University of Isfahan, Isfahan, Iran {Shahbazi,Mokhtari,Dalvi,Ladani}@eng.ui.ac.ir Abstract. ...

Research paper thumbnail of Evolving fuzzy neural network based fire planning in rescue firebrigade agents

... Behrouz Shahgholi Ghahfarokhi, Hamed Shahbazi, Mohammad Kazemifard, Kamran Zamanifar Departme... more ... Behrouz Shahgholi Ghahfarokhi, Hamed Shahbazi, Mohammad Kazemifard, Kamran Zamanifar Department of Computer Engineering, University of Isfahan, HezarJarib Street, Isfahan, Iran shahgholi,rescue_esfahan, kazemifard, zamanifar ... [2] Buckley, JJ, Eslami, E., Esfandiar, E ...

Research paper thumbnail of The structure of personality-based emotional decision making in robotic rescue agent

2008 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, 2008

Abstract One of the most important factors which can affect decision making in a disaster environ... more Abstract One of the most important factors which can affect decision making in a disaster environment is the structure of the agent's personality. It is obvious that the more the agent is able to control its emotions in harmful environments, the better it can perform its task. In this paper we ...

Research paper thumbnail of Generation of rhythmic hand movements in humanoid robots by a neural imitation learning architecture

Biologically Inspired Cognitive Architectures, 2017

Abstract This paper presents a two layer system for imitation learning in humanoid robots. The fi... more Abstract This paper presents a two layer system for imitation learning in humanoid robots. The first layer of this system records complicated and rhythmic movement of the trainer using a motion capture device. It solves an inverse kinematic problem with the help of an adaptive Neuro-Fuzzy Inference system. Then it can achieve angles records of any joints involved in the desired motion. The trajectory is given as input to the systems second layer. The layer deals with extracting optimal parameters of the trajectories obtained from the first layer using a network of oscillator neurons and Particle Swarm Optimization algorithm. This system is capable to obtain any complex motion and rhythmic trajectory via first layer and learns rhythmic trajectories in the second layer then converge towards all these movements. Moreover, this two layer system is able to provide various features of a learner model, for instance resistance against perturbations, modulation of trajectories amplitude and frequency. The simulation results of the learning system is performed in the robot simulator WEBOTS linked with MATLAB software. Practical implementation on an NAO robot demonstrate that the robot has learned desired motion with high accuracy. These results show that proposed system in this paper produces high convergence rate and low test error.

Research paper thumbnail of Implementation of Imitation Learning using Natural Learner Central Pattern Generator Neural Networks

Neural Networks, 2016

In this paper a new design of neural networks is introduced, which is able to generate oscillator... more In this paper a new design of neural networks is introduced, which is able to generate oscillatory patterns. The fundamental building block of the neural network is O-neurons that can generate an oscillation in its transfer functions. Since the natural policy gradient learning has been used in training a central pattern generator paradigm, it is called Natural Learner CPG Neural Networks (NLCPGNN). O-neurons are connected and coupled to each other in order to shape a network and their unknown parameters are found by a natural policy gradient learning algorithm. The main contribution of this paper is design of this learning algorithm which is able to simultaneously search for the weights and topology of the network. This system is capable to obtain any complex motion and rhythmic trajectory via first layer and learn rhythmic trajectories in the second layer and converge towards all these movements. Moreover this two layers system is able to provide various features of a learner model for instance resistance against perturbations, modulation of trajectories amplitude and frequency. Simulation of the learning system in the robot simulator (WEBOTS) that is linked with MATLAB software has been done. Implementation on a real NAO robot demonstrates that the robot has learned desired motion with high accuracy. These results show proposed system produces high convergence rate and low test errors.

Research paper thumbnail of Curvilinear Bipedal Walk Learning in Nao Humanoid Robot Using a CPG Based Policy Gradient Method

Applied Mechanics and Materials, Jan 13, 2012

In this paper we will introduce a new learning approach for curvilinear bipedal walking of Nao hu... more In this paper we will introduce a new learning approach for curvilinear bipedal walking of Nao humanoid robot using policy gradient method. A policy of walking is modeled by some policy parameters controlling some factors in programmable central pattern generators. A “Programmable” central pattern generator is made with coupled nonlinear oscillators capable to shape their state equations with some training trajectories. The proposed model has many benefits including smooth walking patterns, and modulation during walking to increase or decrease its speed. A suitable curvilinear walk was achieved, which is very similar to human ordinary walking. This model can be extended and used in Nao soccer player both in standard platform and 3D soccer simulation leagues of Robocup competitions to train different types of motions.

Research paper thumbnail of Demonstration learning of robotic skills using repeated suggestions learning algorithm

Biologically inspired cognitive architectures, Apr 1, 2017

In this paper a new model of nonlinear dynamical system based on adaptive frequency oscillators f... more In this paper a new model of nonlinear dynamical system based on adaptive frequency oscillators for learning rhythmic signals is implemented by demonstration. This model uses coupled Hopf oscillators to encode and learn any periodic input signal. Learning process is completely implemented in the dynamics of adaptive oscillators. One of the issues in learning in such systems is constant number of oscillators in the feedback loop. In other words, the number of adaptive frequency oscillators is one of the design factors. In this contribution, it is shown that using enough number of oscillators can help the learning process. In this paper, we address this challenge and try to solve it in order to learn the rhythmic movements with greater accuracy, lower error and avoid missing fundamental frequency. To reach this aim, a method for generating drumming patterns is proposed which is able to generate rhythmic and periodic trajectories for a NAO humanoid robot. To do so, a programmable central pattern generator is used which is inspired from animal's neural systems and these programmable central pattern generators are extended to learn patterns with more accuracy for NAO humanoid robots. Successful experiments of demonstration learning are done using simulation and a NAO Real robot.

Research paper thumbnail of Design , manufacturing and test of a wearable device to monitor athlete ' s body movements

In this paper a device based on wearable sensors is introduced to describe quantitative body move... more In this paper a device based on wearable sensors is introduced to describe quantitative body movements in different sports. This device can be an alternative of Image processing techniques. Image processing devices have always been used to describe quantitative body movements, which in addition to being costly, have to be used in specific conditions. The device is built from a number of wireless modules that are easy to use in real-world environments with no limitations. In this method, a quantitative description of movement is made by wireless modules and is performed by the data collected from these modules. In order to analyze the data that was extracted from an athlete's body movements with these wearable sensors, the outputs are simulated in Matlab, and some of its kinematic and kinetic parameters have been studied. Then, at the end of this paper, the quality of movement of a professional athlete and a beginner athlete are compared, and the result is shown. Kinematic and dy...

Research paper thumbnail of Design and Implementation of a Neural Intelligent Controller and a Hybrid PD Controller for Quadrotor

هلاقم تاعلاطا هدیکچ لماک یشهوژپ هلاقم :تفایرد 01 تشهبیدرا 1396 :شریذپ 05 رویرهش 1396 :تیاس رد هئا... more هلاقم تاعلاطا هدیکچ لماک یشهوژپ هلاقم :تفایرد 01 تشهبیدرا 1396 :شریذپ 05 رویرهش 1396 :تیاس رد هئارا 28 رهم 1396 تابر عاونا زا یکی روتورداوک یم هدنرپ یاه هب هک دشاب .تسا هتفرگ رارق ناققحم زا یرایسب هجوت دروم یزاورپ دومع تیلباق و هداس راتخاس لیلد ادیدش کیمانید لیلد هب متسیس نیا یرادیاپ هژیو تیمها زا یطخریغ یا یاهرلرتنک هلاقم نیا رد متسیس نیا یزاسرادیاپ یارب .تسا رادروخرب رلرتنک ،یبیکرت کیسلاک PD هکبش و هیبش و یحارط یبصع یاه هدش یزاس شزومآ ییاناوت اب یبصع هکبش کی یحارط هب ادتبا هلاقم نیا رد .دنا اب ار دوخ یشزومآ هداد هب زاین نودب هکبش نیا .تسا هدش هتخادرپ طخرب یم میظنت ار هکبش بیارض و هداد قیبطت متسیس رلرتنک کی سپس .دنک کیسلاک PD هب هک یبصع هکبش کی زا هدافتسا اب سپس و هدش نایب زلوکین رلگیز شور زا هدافتسا اب تروص آ هب ،هدش هداد شزومآ نیلان یم هتخادرپ رلرتنک نیا یلرتنک یاهرتماراپ میظنت نیا ییاراک نییعت یارب .دوش هیبش ،اهرلرتنک هیبش طیحم رد یزاس بلتم یزاس و تفرگ ماجنا جیاتن یلمع لکش هب هدروآ هیبش لدم کی ،یعقاو متسیس یور اهرلرتنک نیا یزاس هدایپ یارب .تسا هدش اب هک هدش هئارا روتورداوک یارب ...

Research paper thumbnail of Imitation Learning of Complex Behaviors to Humanoid Robots using Evolutionary Optimization of Neural Network of Unit Pattern Generator

In this paper, a system based on neural structures known as central pattern generator is presente... more In this paper, a system based on neural structures known as central pattern generator is presented which enables to acquire the required patterns to move a robot based on a demonstration training. Unit pattern generator can be divided to two subsystems, one is a rhythmic system and the other is a discrete system. The first subsystem is responsible to produce short movements and the second subsystem is responsible to produce rhythmic movements. The special learning algorithm is designed to use these unit pattern generators. Joints and limbs of robot were controlled by Kinect sensor in real time by recognition of the human body skeleton. The work steps were done in this way that the motion sequences of teacher’ body were recorded by Kinect sensor, then transmitted to the computer. These motion sequences teach some nonlinear oscillators then they reproduce motions for humanoid robot. As a result, humanoid body joints imitate the teacher movement in a real time. The main contribution of...

Research paper thumbnail of Developing Imitation Learning to Produce Rhythmic Motion of Drumming in Nao Humanoid Robot Using Superellipses

This paper discussed the development of imitation learning in Nao humanoid robot inspired by cent... more This paper discussed the development of imitation learning in Nao humanoid robot inspired by central pattern generator. Purpose of imitation learning is to enable people to teach new skills to robots via showing examples to them. In sum, the issue studied in this paper was imitation learning for rhythmic actions. Basics of robot learning in this paper included appropriate demonstration techniques, understanding teachers' demonstrations, and an introduction to reinforcement learning. The proposed method was formed based on the evolution of past techniques and superellipses were used to extend the application of imitation learning in drumming. Superellipses, as a wide range of closed geometric curves, are very important for engineers, because they have helpful and precise features in terms of design, programming, and control. The advantage of the proposed method was in the ability to encode learned periodic signals as a limit cycle of superellipses, which influenced louder or lowe...

Research paper thumbnail of Design and implementation of attitude PID controller with fuzzy system to adjust the controller gain values for quadrotor

دییامن هدافتسا لیذ ترابع زا هلاقم نیا هب عاجرا يارب : Please cite this article using: V. Tikani, ... more دییامن هدافتسا لیذ ترابع زا هلاقم نیا هب عاجرا يارب : Please cite this article using: V. Tikani, H. Shahbazi, Design and implementation of attitude PID controller with fuzzy system to adjust the controller gain values for quadrotor, Modares Mechanical Engineering, Vol. 16, No. 9, pp. 19-28, 2016 (in Persian) هدایپ و یحارط هیواز رلرتنک يزاس يا PID هرهب اب میظنت يارب يزاف متسیس زا يریگ هرهب یلرتنک ياه روتورداوک

Research paper thumbnail of Practical implementation of a PID-Model Reference Adaptive Controller for a 2-DOF Camera Gimbal

هلاقم تاعلاطا هدیکچ لماک یشهوژپ هلاقم :تفایرد 06 نیدرورف 1396 :شریذپ 09 ادرخ د 1396 :تیاس رد هئار... more هلاقم تاعلاطا هدیکچ لماک یشهوژپ هلاقم :تفایرد 06 نیدرورف 1396 :شریذپ 09 ادرخ د 1396 :تیاس رد هئارا 06 م دادر 1396 رتماراپ راکدوخ میظنت تهج عجرم لدم یقیبطت لرتنک شور ،هلاقم نیا رد رادیاپ کی رلرتنک یاه یم هئارا نیبرود زاس خساپ هک یوحنب ،دوش یدحاو عجرم لدم خساپ زا فلتخم یسرنیا طیارش تحت متسیس رادیاپ .دیامن یوریپ هک تسا کرحتم هیاپ کی رب لمتشم لابمیگ ای نیبرود زاس راومه تیلباق ،نیبرود هب لاعفریغ ای لاعف لاصتا اب شخرچ لباقم رد ریواصت تیبثت و تکرح یزاس شزرل و اه راد ار وکس یاه د تلاکشم زا یکی . لابمیگ یاه یراجت هب رداق طقف هک تسا نیا رازاب رد دوجوم نیبرود لمح یم دوخ هب صوصخم یاه نیا یور رب یرگید نیبرود رگا و دنشاب لابمیگ یمن ،دوش هتسب اه نیبرود مرج زکرم لحم و یسرنیا توافت لیلد هب لکشم نیا .دننک ظفح ار دوخ هیلوا بسانم درکلمع دنناوت فلتخم یاه .تسا رگیدکی اب ور ،لکشم نیا لح یاتسار رد ،هلاقم نیا رد هدایپ یعقاو متسیس یور رب ونیودرآ درب کمک هب یگنردلاب یرلرتنک ش یلمع یزاس رلرتنک یلمع یزاس هدایپ سپس و هدیدرگ ماجنا یدازآ هجرد ود لابمیگ تخاس و یحارط ادتبا رد .تسا هدش PID یور رب عجرم لدم یقیبطت ع یس...

Research paper thumbnail of Design PID and Fractional-Order PID Controller and Experimental Evaluation of PID Controller Performance for Attitude Control of Quadrotor

The purpose of this paper is to design a fractional order PID (FOPID) controller base on stochast... more The purpose of this paper is to design a fractional order PID (FOPID) controller base on stochastic algorithms for attitude control of quadrotor. The model is based on usage of Fractional calculus in the PID Controllers which can provide novel and higher performance extension for FOPID controllers. Here, the main goal is to design an optimal PID and FOPID controller using stochastic algorithms. Therefor two stochastic algorithms are used for optimal tuning of FOPID parameters. Genetic Algorithm (GA) and Particle Swarm Optimization are compared in minimizing the performance criteria formula which leads to a better performance in controlling of the plant. A quadrotor is installed on an experimental test stand includes of accelerometers, gyroscopes and microcontroller with one and three degrees of freedom to test the performance of PID controller. Kalman filter is used to reduce the noises by combination of accelerometer and gyroscope output. The result of the experiments in the paper ...

Research paper thumbnail of Modeling the Drivers of Eco-Innovation Adoption within Iranian Manufacturing Small and Medium-Sized Enterprises

International Journal of Applied Operational Research - An Open Access Journal, 2017

There are various studies on the eco-innovation in the literature, but there is a scarcity of stu... more There are various studies on the eco-innovation in the literature, but there is a scarcity of studies on the adoption and diffusion within manufacturing small and medium-size enterprises (SMEs). Drivers to adopt eco-innovations by manufacturing SMEs are required to be understood properly and be analyzed regarding the relationships among them. Hence, the purpose of this study is to identify the main drivers of eco-innovation adoption by Iranian manufacturing SMEs from the literature and further model them based on experts’ opinions. We have utilized the valuable opinions of experts to develop a hierarchical model of drivers utilizing Interpretive Structural Modeling approach to demonstrate the contextual interrelationship among these factors. Furthermore, degrees of relationships among the drivers were obtained according to Matrice d'Impacts Croises Multipication Applique ́ an Classment analysis approach. Identification and modeling of eco-innovation drivers is expected to assist...

Research paper thumbnail of Moderating Effects of Demographics on Green Information System Adoption

International Journal of Innovation and Technology Management, 2019

The important role of demographics on technology adoption has been highlighted vastly in the lite... more The important role of demographics on technology adoption has been highlighted vastly in the literature. Therefore, this study aims at investigating the moderating role of managers’ demographics in their decision-making process to adopt Green information system (Green IS) from the lens of norm activation theory. With 175 valid questionnaires hand collected from organizations’ decision-makers, the researchers examined the research model and its related hypotheses utilizing the Partial Least Squares (PLS)–Structural Equation Modeling (SEM). The results showed Green IS attitude together with personal norm to be the most influential factors, followed by environmental attitude. In addition, we found that while awareness of consequences significantly impacted personal norms, its explanatory power on personal norms was higher when it was mediated through ascription of responsibility. Regarding the moderator variables, the model explained better the pro-environmental behavioral intention of...

Research paper thumbnail of Factors Influencing Beliefs Formation towards the Adoption of Social Commerce in SME Travel Agencies

Economics & Sociology, 2018

The purpose of this study is to investigate the factors that influence beliefs formation towards ... more The purpose of this study is to investigate the factors that influence beliefs formation towards the adoption of social commerce in SME travel agencies. Accordingly, a distal-proximal model is developed to study CEOs' beliefs towards the usefulness of social commerce. Data were collected through a questionnaire survey of travel agencies' CEOs in Isfahan, Iran. With 180 collected data from respondents, the Partial Least Squares-Structural Equation Modeling approach was taken to assess both measurement and structural models of the study. The results revealed that CEOs' innovativeness and attitude towards IT as individual factors, and organizational resources as institutional factor were significantly explained beliefs formation of respondents towards the usefulness of social commerce. However, it was found that the influences of CEOs' IT knowledge, subjective norms (professional peers, employees) and firm size on perceived usefulness were found insignificant. Implications of the study are further discussed.

Research paper thumbnail of The moderating effect of experience on the intention to adopt mobile social network sites for pedagogical purposes: An extension of the technology acceptance model

Education and Information Technologies, 2018

With numerous benefits of utilising mobile social network sites (SNSs) for learning purposes, lim... more With numerous benefits of utilising mobile social network sites (SNSs) for learning purposes, limited studies have been conducted to determine the factors that influence the adoption of mobile SNSs in facilitating learning. Accordingly, the main purpose of this study is to explore the determinants of students' behavioural intention to use mobile SNSs for their pedagogical purposes by utilising an extended version of Technology Acceptance Model. Furthermore, the moderating effect of users' experience on their behavioural intention was investigated. Using a structured questionnaire, data were collected from 600 students from top-five public universities of Malaysia. The results revealed perceived task-technology fit as the great predictor of users' intention and perceived usefulness. Although the moderating impact of students'

Research paper thumbnail of Demonstration learning of robotic skills using repeated suggestions learning algorithm

Biologically Inspired Cognitive Architectures, 2017

In this paper a new model of nonlinear dynamical system based on adaptive frequency oscillators f... more In this paper a new model of nonlinear dynamical system based on adaptive frequency oscillators for learning rhythmic signals is implemented by demonstration. This model uses coupled Hopf oscillators to encode and learn any periodic input signal. Learning process is completely implemented in the dynamics of adaptive oscillators. One of the issues in learning in such systems is constant number of oscillators in the feedback loop. In other words, the number of adaptive frequency oscillators is one of the design factors. In this contribution, it is shown that using enough number of oscillators can help the learning process. In this paper, we address this challenge and try to solve it in order to learn the rhythmic movements with greater accuracy, lower error and avoid missing fundamental frequency. To reach this aim, a method for generating drumming patterns is proposed which is able to generate rhythmic and periodic trajectories for a NAO humanoid robot. To do so, a programmable central pattern generator is used which is inspired from animal's neural systems and these programmable central pattern generators are extended to learn patterns with more accuracy for NAO humanoid robots. Successful experiments of demonstration learning are done using simulation and a NAO Real robot.

Research paper thumbnail of Mechatronic design and construction of a five axes satellite simulator

2016 4th International Conference on Robotics and Mechatronics (ICROM), 2016

This article describes the construction of a five spacecraft flight simulator based on an air bea... more This article describes the construction of a five spacecraft flight simulator based on an air bearing system, which was designed and instrumented in university of Isfahan laboratory to evaluate and to perform research in the field of Attitude Determination and Control Systems for spacecraft. This simulator is modeled in Autodesk-Inventor software package to design the simulator component precisely. The hardware and software components of the testbed are detailed in this article. the constraints for the construction and final realization of this attitude simulator testbed are depicted. It describes all modifications needed to reconfigure the simulator system testbed.

Research paper thumbnail of A New Approach for Scoring Relevant Documents by Applying a Farsi Stemming Method in Persian Web Search Engines

... Search Engines Hamed Shahbazi, Alireza Mokhtaripour, Mohammad Dalvi, and Behrouz Tork Ladani ... more ... Search Engines Hamed Shahbazi, Alireza Mokhtaripour, Mohammad Dalvi, and Behrouz Tork Ladani Department of computer engineering University of Isfahan, Isfahan, Iran {Shahbazi,Mokhtari,Dalvi,Ladani}@eng.ui.ac.ir Abstract. ...

Research paper thumbnail of Evolving fuzzy neural network based fire planning in rescue firebrigade agents

... Behrouz Shahgholi Ghahfarokhi, Hamed Shahbazi, Mohammad Kazemifard, Kamran Zamanifar Departme... more ... Behrouz Shahgholi Ghahfarokhi, Hamed Shahbazi, Mohammad Kazemifard, Kamran Zamanifar Department of Computer Engineering, University of Isfahan, HezarJarib Street, Isfahan, Iran shahgholi,rescue_esfahan, kazemifard, zamanifar ... [2] Buckley, JJ, Eslami, E., Esfandiar, E ...

Research paper thumbnail of The structure of personality-based emotional decision making in robotic rescue agent

2008 IEEE/ASME International Conference on Advanced Intelligent Mechatronics, 2008

Abstract One of the most important factors which can affect decision making in a disaster environ... more Abstract One of the most important factors which can affect decision making in a disaster environment is the structure of the agent's personality. It is obvious that the more the agent is able to control its emotions in harmful environments, the better it can perform its task. In this paper we ...

Research paper thumbnail of Generation of rhythmic hand movements in humanoid robots by a neural imitation learning architecture

Biologically Inspired Cognitive Architectures, 2017

Abstract This paper presents a two layer system for imitation learning in humanoid robots. The fi... more Abstract This paper presents a two layer system for imitation learning in humanoid robots. The first layer of this system records complicated and rhythmic movement of the trainer using a motion capture device. It solves an inverse kinematic problem with the help of an adaptive Neuro-Fuzzy Inference system. Then it can achieve angles records of any joints involved in the desired motion. The trajectory is given as input to the systems second layer. The layer deals with extracting optimal parameters of the trajectories obtained from the first layer using a network of oscillator neurons and Particle Swarm Optimization algorithm. This system is capable to obtain any complex motion and rhythmic trajectory via first layer and learns rhythmic trajectories in the second layer then converge towards all these movements. Moreover, this two layer system is able to provide various features of a learner model, for instance resistance against perturbations, modulation of trajectories amplitude and frequency. The simulation results of the learning system is performed in the robot simulator WEBOTS linked with MATLAB software. Practical implementation on an NAO robot demonstrate that the robot has learned desired motion with high accuracy. These results show that proposed system in this paper produces high convergence rate and low test error.

Research paper thumbnail of Implementation of Imitation Learning using Natural Learner Central Pattern Generator Neural Networks

Neural Networks, 2016

In this paper a new design of neural networks is introduced, which is able to generate oscillator... more In this paper a new design of neural networks is introduced, which is able to generate oscillatory patterns. The fundamental building block of the neural network is O-neurons that can generate an oscillation in its transfer functions. Since the natural policy gradient learning has been used in training a central pattern generator paradigm, it is called Natural Learner CPG Neural Networks (NLCPGNN). O-neurons are connected and coupled to each other in order to shape a network and their unknown parameters are found by a natural policy gradient learning algorithm. The main contribution of this paper is design of this learning algorithm which is able to simultaneously search for the weights and topology of the network. This system is capable to obtain any complex motion and rhythmic trajectory via first layer and learn rhythmic trajectories in the second layer and converge towards all these movements. Moreover this two layers system is able to provide various features of a learner model for instance resistance against perturbations, modulation of trajectories amplitude and frequency. Simulation of the learning system in the robot simulator (WEBOTS) that is linked with MATLAB software has been done. Implementation on a real NAO robot demonstrates that the robot has learned desired motion with high accuracy. These results show proposed system produces high convergence rate and low test errors.

Research paper thumbnail of Curvilinear Bipedal Walk Learning in Nao Humanoid Robot Using a CPG Based Policy Gradient Method

Applied Mechanics and Materials, Jan 13, 2012

In this paper we will introduce a new learning approach for curvilinear bipedal walking of Nao hu... more In this paper we will introduce a new learning approach for curvilinear bipedal walking of Nao humanoid robot using policy gradient method. A policy of walking is modeled by some policy parameters controlling some factors in programmable central pattern generators. A “Programmable” central pattern generator is made with coupled nonlinear oscillators capable to shape their state equations with some training trajectories. The proposed model has many benefits including smooth walking patterns, and modulation during walking to increase or decrease its speed. A suitable curvilinear walk was achieved, which is very similar to human ordinary walking. This model can be extended and used in Nao soccer player both in standard platform and 3D soccer simulation leagues of Robocup competitions to train different types of motions.