The rotational and translational motion of nanocars and nanotrucks as well as their motion regime... more The rotational and translational motion of nanocars and nanotrucks as well as their motion regimes at different temperatures are investigated. In recent years, few similar types of molecular machines have been simulated. In contrast to previous studies which have used the Rigid-Body Molecular Dynamics (RB MD) method, an all-atom model and classic atomistic dynamics have been employed in this paper to achieve better accuracy. Our results demonstrated that the flexibility of the chassis and its attachment to the gold surface play important roles in the motion of a nanocar. In fact, a heavier and more flexible nanocar chassis reduces its speed compared to a nanotruck. In addition, simulations results are compared with available data from experimental studies done in recent years, and an acceptable agreement between the simulation results and experiments was observed. It was found that both molecules have three different regimes of motion, and the translational and rotational motion are...
Exploiting a surface subjected to a temperature gradient to convert the diffusive motion of nanoc... more Exploiting a surface subjected to a temperature gradient to convert the diffusive motion of nanocars to guided directional motion.
International Journal of Advanced Robotic Systems, 2012
Washing the corpse and dressing the body prior to burial is an act of love and necessity in many ... more Washing the corpse and dressing the body prior to burial is an act of love and necessity in many religions. Applying robotics and automation technologies for the washing and preparation of a deceased Muslim in accordance with the Islamic Shari'at laws has been the challenging foundation of this research. With an increasing annual population growth resulting in an increase in the number of deaths (historically and/or immediately after a national disaster), automating part of this procedure to increase the speed of operation, reducing the health risks to the personnel of washing rooms “Ghassalkhaneh” at the cemeteries and enhancing their quality of life have been the primary objectives of this project. We have named and patented this semi-automated corpse preparation machine as the “PaakShooy” or “پاک شوی” in Persian (Farsi) which means purifying the deceased. The whole process is composed of three operational units lined up in a series; the automatic washing chamber, drying cell ...
Washing the body and dressing the corpse prior to burial is an act of love and necessity in many ... more Washing the body and dressing the corpse prior to burial is an act of love and necessity in many religions. Applying robotics and automation technologies for washing and preparation of a deceased Moslem in accordance to the Islamic Shari’a laws has been the challenging foundation of this research. With increasing annual population growth and as a result an increase in number of deaths (historically and/or immediately after a national disaster), automating part of this procedure to increase speed of operation, reducing the health risks to the personnel of washing rooms “Ghassalkhaneh” at the cemeteries and enhancing their quality of life has been the utmost objective of this project. We have named and patented this semi-automated corpse preparation machine as the “PaakShooy” or “ ??? ??? ” in Persian (Farsi) which means purifying the deceased. The whole process is composed of three operational units lined up in series; the automatic washing chamber, drying cell, and the semi-automatic shrouding table. This paper covers an introductory concept of the subject in Islam, a conceptual design of various machines and mechanism to automate the important tasks in accordance to Islamic laws, and the final detailed design, simulation, and animation of the PaakShooy machine. In doing so, consultation with Islamic scholars has been a priority from the beginning of the project to the end.
Physical chemistry chemical physics : PCCP, Jan 20, 2017
A new method for guiding the motion of fullerene and fullerene-based nanocars is introduced in th... more A new method for guiding the motion of fullerene and fullerene-based nanocars is introduced in this paper. The effects of non-flat substrates on the motion of C60, a nanocar and a nanotruck are investigated at different conditions and temperatures. Their behavior is studied using two different approaches: analyzing the variation in potential energy and conducting all-atom classical molecular dynamics simulations. This paper proposes that the use of a stepped substrate will make their motion more predictable and controllable. The results of the simulations show that C60 stays on the top side of the step and cannot jump over the step at temperatures of 400 K and lower. However, at temperatures of 500 K and higher, C60 has sufficient energy to travel to the down side of the step. C60 attaches to the edge and moves just alongside of the edge when it is on the down side of the step. The edge also restricts the motion of C60 alongside the edge and reduces its range of motion. By consideri...
2016 International Conference on Manipulation, Automation and Robotics at Small Scales (MARSS), 2016
In this paper we have studied the motion of a nanocar and nanotruck on gold substrate using the c... more In this paper we have studied the motion of a nanocar and nanotruck on gold substrate using the classical molecular dynamics method. Analyzing the motion regime of the nanocar at different temperatures is one of the main goals of this paper. In the past years, similar molecules such as Trimmer, Z-car and nanotruck have been simulated by Konyukhov and Akimov. To increase the modeling accuracy in this paper we have used classical molecular dynamics contrary to previous works which used a rigid body molecular dynamics method. The result of our simulations were compared qualitatively to the experimental tests performed by Zhang et al. [12]. There was a good agreement between the results achieved from our simulations and the experimental observations. We found that the motion of both molecules can be divided into 3 different regimes: immobility at 200K and lower temperatures, short range displacements between 200K to 400K, and long range movements at 500 K and higher temperatures. Furthermore, the bigger and more flexible chassis of a nanocar reduces the speed of the nanocar with respect to a nanotruck. The results lead to the better understanding of nanocar motion and reveal exclusive motion details of both molecules and elucidate their use in practical applications.
ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, Volume 5, 2010
In this paper, an adaptive control scheme for multi-agent formation control is proposed. This con... more In this paper, an adaptive control scheme for multi-agent formation control is proposed. This control method is based on artificial potential functions integrated with adaptive fuzzy sliding mode control technique. We consider fully actuated mobile agents with completely unknown dynamics. An adaptive fuzzy logic system is used to approximate the unknown system dynamics. Sliding Mode Control (SMC) theory is used to force agents’ motion to obey the dynamics defined by the simple inter-agent artificial potential functions. Stability proof is given using Lyapunov functions, which shows the robustness of controller with respect to disturbances and system uncertainties. Simulation results are demonstrated for a multi-agent formation problem, illustrating the effectiveness of the proposed method. Experimental results are included to verify the applicability of the scheme for a test-bed of six real mobile robots.
Abstract In this paper, we have studied the motion of buckminsterfullerene (C60) on a gold surfac... more Abstract In this paper, we have studied the motion of buckminsterfullerene (C60) on a gold surface by analyzing its potential energy and using classical molecular dynamics method. The results can be employed to investigate the motion of C60-based nanocars which have been made in recent years. For this purpose, we have studied the translational and rotational motions of C60 molecule independently. First, we have calculated the potential energy of a C60 molecule on a gold surface in different orientations and positions and employed this data to predict fullerene motion by examining its potential energy. Then we have simulated the motion of C60 at different temperatures using classical molecular dynamics methods. Specifying the regime of the motion at different temperatures is one of main goals of this paper. We have found that the rotational motion of C60 molecule on the gold substrate, was easier than its sliding (translational) motion. Also, the regime of motion of fullerene depended on temperature. The results demonstrate that three different regimes of motion, dependent on temperature, could be observed: rare jumps to adjacent cells, frequent jumps, and continuous motion. Employing the results of this paper not only helps to understand the C60 motion on the gold surface but also provides an appropriate tool for realizing motion of the thermally-driven fullerene-based nanocars.
In this paper, a novel decentralized adaptive control scheme for multiagent formation control is ... more In this paper, a novel decentralized adaptive control scheme for multiagent formation control is proposed based on an integration of artificial potential functions with robust control techniques. Fully actuated mobile agents with partially unknown models are considered, where an adaptive fuzzy logic system is used to approximate the unknown system dynamics. The robust performance criterion is used to attenuate the adaptive fuzzy approximation error and external disturbances to a prescribed level. The advantages of the proposed controller can be listed as robustness to input nonlinearity, external disturbances, and model uncertainties, and applicability on a large diversity of autonomous systems. A Lyapunov-function-based proof is given of robust stability, which shows the robustness of the controller with respect to disturbances and system uncertainties. Simulation results are demonstrated for a swarm formation problem of a group of six holonomic robots, illustrating the effective attenuation of approximation errors and external disturbances, even in the case of agent failure. Moreover, experimental results confirm the validity of the presented approach and are included to verify the applicability of the scheme for a swarm of six real holonomic robots.
The rotational and translational motion of nanocars and nanotrucks as well as their motion regime... more The rotational and translational motion of nanocars and nanotrucks as well as their motion regimes at different temperatures are investigated. In recent years, few similar types of molecular machines have been simulated. In contrast to previous studies which have used the Rigid-Body Molecular Dynamics (RB MD) method, an all-atom model and classic atomistic dynamics have been employed in this paper to achieve better accuracy. Our results demonstrated that the flexibility of the chassis and its attachment to the gold surface play important roles in the motion of a nanocar. In fact, a heavier and more flexible nanocar chassis reduces its speed compared to a nanotruck. In addition, simulations results are compared with available data from experimental studies done in recent years, and an acceptable agreement between the simulation results and experiments was observed. It was found that both molecules have three different regimes of motion, and the translational and rotational motion are...
Exploiting a surface subjected to a temperature gradient to convert the diffusive motion of nanoc... more Exploiting a surface subjected to a temperature gradient to convert the diffusive motion of nanocars to guided directional motion.
International Journal of Advanced Robotic Systems, 2012
Washing the corpse and dressing the body prior to burial is an act of love and necessity in many ... more Washing the corpse and dressing the body prior to burial is an act of love and necessity in many religions. Applying robotics and automation technologies for the washing and preparation of a deceased Muslim in accordance with the Islamic Shari'at laws has been the challenging foundation of this research. With an increasing annual population growth resulting in an increase in the number of deaths (historically and/or immediately after a national disaster), automating part of this procedure to increase the speed of operation, reducing the health risks to the personnel of washing rooms “Ghassalkhaneh” at the cemeteries and enhancing their quality of life have been the primary objectives of this project. We have named and patented this semi-automated corpse preparation machine as the “PaakShooy” or “پاک شوی” in Persian (Farsi) which means purifying the deceased. The whole process is composed of three operational units lined up in a series; the automatic washing chamber, drying cell ...
Washing the body and dressing the corpse prior to burial is an act of love and necessity in many ... more Washing the body and dressing the corpse prior to burial is an act of love and necessity in many religions. Applying robotics and automation technologies for washing and preparation of a deceased Moslem in accordance to the Islamic Shari’a laws has been the challenging foundation of this research. With increasing annual population growth and as a result an increase in number of deaths (historically and/or immediately after a national disaster), automating part of this procedure to increase speed of operation, reducing the health risks to the personnel of washing rooms “Ghassalkhaneh” at the cemeteries and enhancing their quality of life has been the utmost objective of this project. We have named and patented this semi-automated corpse preparation machine as the “PaakShooy” or “ ??? ??? ” in Persian (Farsi) which means purifying the deceased. The whole process is composed of three operational units lined up in series; the automatic washing chamber, drying cell, and the semi-automatic shrouding table. This paper covers an introductory concept of the subject in Islam, a conceptual design of various machines and mechanism to automate the important tasks in accordance to Islamic laws, and the final detailed design, simulation, and animation of the PaakShooy machine. In doing so, consultation with Islamic scholars has been a priority from the beginning of the project to the end.
Physical chemistry chemical physics : PCCP, Jan 20, 2017
A new method for guiding the motion of fullerene and fullerene-based nanocars is introduced in th... more A new method for guiding the motion of fullerene and fullerene-based nanocars is introduced in this paper. The effects of non-flat substrates on the motion of C60, a nanocar and a nanotruck are investigated at different conditions and temperatures. Their behavior is studied using two different approaches: analyzing the variation in potential energy and conducting all-atom classical molecular dynamics simulations. This paper proposes that the use of a stepped substrate will make their motion more predictable and controllable. The results of the simulations show that C60 stays on the top side of the step and cannot jump over the step at temperatures of 400 K and lower. However, at temperatures of 500 K and higher, C60 has sufficient energy to travel to the down side of the step. C60 attaches to the edge and moves just alongside of the edge when it is on the down side of the step. The edge also restricts the motion of C60 alongside the edge and reduces its range of motion. By consideri...
2016 International Conference on Manipulation, Automation and Robotics at Small Scales (MARSS), 2016
In this paper we have studied the motion of a nanocar and nanotruck on gold substrate using the c... more In this paper we have studied the motion of a nanocar and nanotruck on gold substrate using the classical molecular dynamics method. Analyzing the motion regime of the nanocar at different temperatures is one of the main goals of this paper. In the past years, similar molecules such as Trimmer, Z-car and nanotruck have been simulated by Konyukhov and Akimov. To increase the modeling accuracy in this paper we have used classical molecular dynamics contrary to previous works which used a rigid body molecular dynamics method. The result of our simulations were compared qualitatively to the experimental tests performed by Zhang et al. [12]. There was a good agreement between the results achieved from our simulations and the experimental observations. We found that the motion of both molecules can be divided into 3 different regimes: immobility at 200K and lower temperatures, short range displacements between 200K to 400K, and long range movements at 500 K and higher temperatures. Furthermore, the bigger and more flexible chassis of a nanocar reduces the speed of the nanocar with respect to a nanotruck. The results lead to the better understanding of nanocar motion and reveal exclusive motion details of both molecules and elucidate their use in practical applications.
ASME 2010 10th Biennial Conference on Engineering Systems Design and Analysis, Volume 5, 2010
In this paper, an adaptive control scheme for multi-agent formation control is proposed. This con... more In this paper, an adaptive control scheme for multi-agent formation control is proposed. This control method is based on artificial potential functions integrated with adaptive fuzzy sliding mode control technique. We consider fully actuated mobile agents with completely unknown dynamics. An adaptive fuzzy logic system is used to approximate the unknown system dynamics. Sliding Mode Control (SMC) theory is used to force agents’ motion to obey the dynamics defined by the simple inter-agent artificial potential functions. Stability proof is given using Lyapunov functions, which shows the robustness of controller with respect to disturbances and system uncertainties. Simulation results are demonstrated for a multi-agent formation problem, illustrating the effectiveness of the proposed method. Experimental results are included to verify the applicability of the scheme for a test-bed of six real mobile robots.
Abstract In this paper, we have studied the motion of buckminsterfullerene (C60) on a gold surfac... more Abstract In this paper, we have studied the motion of buckminsterfullerene (C60) on a gold surface by analyzing its potential energy and using classical molecular dynamics method. The results can be employed to investigate the motion of C60-based nanocars which have been made in recent years. For this purpose, we have studied the translational and rotational motions of C60 molecule independently. First, we have calculated the potential energy of a C60 molecule on a gold surface in different orientations and positions and employed this data to predict fullerene motion by examining its potential energy. Then we have simulated the motion of C60 at different temperatures using classical molecular dynamics methods. Specifying the regime of the motion at different temperatures is one of main goals of this paper. We have found that the rotational motion of C60 molecule on the gold substrate, was easier than its sliding (translational) motion. Also, the regime of motion of fullerene depended on temperature. The results demonstrate that three different regimes of motion, dependent on temperature, could be observed: rare jumps to adjacent cells, frequent jumps, and continuous motion. Employing the results of this paper not only helps to understand the C60 motion on the gold surface but also provides an appropriate tool for realizing motion of the thermally-driven fullerene-based nanocars.
In this paper, a novel decentralized adaptive control scheme for multiagent formation control is ... more In this paper, a novel decentralized adaptive control scheme for multiagent formation control is proposed based on an integration of artificial potential functions with robust control techniques. Fully actuated mobile agents with partially unknown models are considered, where an adaptive fuzzy logic system is used to approximate the unknown system dynamics. The robust performance criterion is used to attenuate the adaptive fuzzy approximation error and external disturbances to a prescribed level. The advantages of the proposed controller can be listed as robustness to input nonlinearity, external disturbances, and model uncertainties, and applicability on a large diversity of autonomous systems. A Lyapunov-function-based proof is given of robust stability, which shows the robustness of the controller with respect to disturbances and system uncertainties. Simulation results are demonstrated for a swarm formation problem of a group of six holonomic robots, illustrating the effective attenuation of approximation errors and external disturbances, even in the case of agent failure. Moreover, experimental results confirm the validity of the presented approach and are included to verify the applicability of the scheme for a swarm of six real holonomic robots.
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