Mohd Azizi - Academia.edu (original) (raw)
Papers by Mohd Azizi
IAES International Journal of Robotics and Automation (IJRA)
In human-robot interaction, the use of collaborative robots or cobots in many industries is of ma... more In human-robot interaction, the use of collaborative robots or cobots in many industries is of major importance to researchers in human-robot interaction (HRI). The interaction between human robot carries several challenges, the greatest being the risk of human injury. In addition to reducing the proximity between robots and humans, increased difficulty of human-robot encounters raises the likelihood of accidents only. This paper proposes a virtual collaborative robot in the simulated non-industrial workspace. The safety during human-robot interaction using simulation software was investigated by measuring the risks for planning and control. A reactive robot controller was formulated to minimize the risk during human-robot interaction. A Gazebo software is used in this article, written in Python language, to replicate complex environments that a robot can face. This paper also investigated the robot’s speed. It can be reduced before a collision with a human about to happen, and it m...
23rd ITS World Congress (Melbourne), 2016
A successful Vehicle Collision Avoidance system (VCA) demands a robust and stable algorithm. The ... more A successful Vehicle Collision Avoidance system (VCA) demands a robust and stable algorithm. The authors proposed a VCA Control Strategy using Model Predictive Control (MPC). The strategy includes: 1) threat assessment strategy using safe-distance threshold, 2) vehicle future trajectory prediction in the occurrence of obstacle, 3) decision making prior to avoiding collision, 4) avoiding obstacles while ensuring the vehicle to return to its original trajectory. The MPC-VCA control used a nonlinear vehicle model with steering and braking input as the actuators that will react and avoid collisions. The purpose of this work is to analyse the performance of the MPC-VCA control. These include the study on the effects of having different tuning parameters for the offline tuning methods of MPC (its control and prediction horizons as well as its weighting matrices), comparison of MPC with other control strategy, i.e. the Geometrical-Based Control Method (GMC) and to simulate different-sized obstacle avoidance scenarios for the control. The results are shown and discussed.
PERINTIS eJournal, 2016
Road accidents remain a major cause for fatalities globally. A lot of researches have been done a... more Road accidents remain a major cause for fatalities globally. A lot of researches have been done and it is widely reported that vehicle automation can reduce human errors, thus reducing road fatalities. The construction of a fully autonomous vehicle is among the major developments of vehicle automation. Many surveys have been done about vehicle automation and Advanced Driver Assistance Systems (ADAS) is one of the fundamental features of a fully autonomous vehicle. Main ADAS features include Automatic Cruise Control, Automatic Parking, Collision Avoidance as well as Lane Departure Warning systems. In this paper, current advances of collision mitigation technologies for ADAS are reviewed as an introductory idea for researchers and general audiences who are new to this field. Each of the systems are discussed in their own sections. The highlights and future directions for each system are brought to light. Several future work suggestions for a comprehensive ADAS systems are highlighted. As this work is intended as a general survey on ADAS, the technical specifications of each system are not discussed in details.
2014 IEEE International Conference on Industrial Technology (ICIT), 2014
This paper describes modeling, attitude estimation, attitude control, and altitude control for He... more This paper describes modeling, attitude estimation, attitude control, and altitude control for Hexarotor micro aerial vehicle (MAV). Hexarotor has high potential to carry more payload and high maneuverability compared to quadrotor. This paper proposes a new approach for attitude estimation in real- time system by using a nonlinear complementary observer based on special orthogonal group of rotation matrices SO(3), rather than conventional extended Kalman filter (EKF), to exploit the near-global convergence property of the observer and reduced computational complexity. The proposed attitude controller is based on an inner-outer loop structure PI+PID (proportional- integral plus proportional-integral-derivative) control method to reduce the overshoot effects, leads to faster response, improve robustness and transient response, whilst the proposed altitude controller is based on classical closed loop PID control system. Simulation results will be presented showing the proposed controller achieves excellent dynamical performance and finally, the experimental results, both in indoor and outdoor flying environment demonstrate the effectiveness of the proposed attitude observer and controller in real flight condition.
The huge developments in the field of magnetorheological (MR) fluid-based devices will have a gre... more The huge developments in the field of magnetorheological (MR) fluid-based devices will have a great influence on the future of mechatronic applications due to the ease of interfacing between electronic controls and the mechanical components that they provide. Among various MR fluid-based devices, an MR valve would be particularly significant for the development of other devices, if it could be successfully achieved. One of the most challenging obstacles to MR valve development is the difficulty of achieving device miniaturization while, at the same time, improving the achievable performance. This study demonstrates a novel design for an MR valve, using the meandering flow path approach in order to increase the effective area so that the MR fluid can be regulated within a small-sized valve. The meandering flow path is formed by combining multiple annular, radial and orifice flow channels. In order to analyze the valve performance, a mathematical model of the proposed MR valve is derived and combined with numerical simulation using the finite element method, with the intention of predicting the achievable pressure drop that can be generated by the valve. The predicted MR valve performances are then experimentally evaluated using an oscillation-disturbed bypass hydraulic cylinder. The simulation results show that the proposed MR valve design could yield substantial pressure drop improvement, which is confirmed by the experiment.
IAES International Journal of Robotics and Automation (IJRA)
In human-robot interaction, the use of collaborative robots or cobots in many industries is of ma... more In human-robot interaction, the use of collaborative robots or cobots in many industries is of major importance to researchers in human-robot interaction (HRI). The interaction between human robot carries several challenges, the greatest being the risk of human injury. In addition to reducing the proximity between robots and humans, increased difficulty of human-robot encounters raises the likelihood of accidents only. This paper proposes a virtual collaborative robot in the simulated non-industrial workspace. The safety during human-robot interaction using simulation software was investigated by measuring the risks for planning and control. A reactive robot controller was formulated to minimize the risk during human-robot interaction. A Gazebo software is used in this article, written in Python language, to replicate complex environments that a robot can face. This paper also investigated the robot’s speed. It can be reduced before a collision with a human about to happen, and it m...
23rd ITS World Congress (Melbourne), 2016
A successful Vehicle Collision Avoidance system (VCA) demands a robust and stable algorithm. The ... more A successful Vehicle Collision Avoidance system (VCA) demands a robust and stable algorithm. The authors proposed a VCA Control Strategy using Model Predictive Control (MPC). The strategy includes: 1) threat assessment strategy using safe-distance threshold, 2) vehicle future trajectory prediction in the occurrence of obstacle, 3) decision making prior to avoiding collision, 4) avoiding obstacles while ensuring the vehicle to return to its original trajectory. The MPC-VCA control used a nonlinear vehicle model with steering and braking input as the actuators that will react and avoid collisions. The purpose of this work is to analyse the performance of the MPC-VCA control. These include the study on the effects of having different tuning parameters for the offline tuning methods of MPC (its control and prediction horizons as well as its weighting matrices), comparison of MPC with other control strategy, i.e. the Geometrical-Based Control Method (GMC) and to simulate different-sized obstacle avoidance scenarios for the control. The results are shown and discussed.
PERINTIS eJournal, 2016
Road accidents remain a major cause for fatalities globally. A lot of researches have been done a... more Road accidents remain a major cause for fatalities globally. A lot of researches have been done and it is widely reported that vehicle automation can reduce human errors, thus reducing road fatalities. The construction of a fully autonomous vehicle is among the major developments of vehicle automation. Many surveys have been done about vehicle automation and Advanced Driver Assistance Systems (ADAS) is one of the fundamental features of a fully autonomous vehicle. Main ADAS features include Automatic Cruise Control, Automatic Parking, Collision Avoidance as well as Lane Departure Warning systems. In this paper, current advances of collision mitigation technologies for ADAS are reviewed as an introductory idea for researchers and general audiences who are new to this field. Each of the systems are discussed in their own sections. The highlights and future directions for each system are brought to light. Several future work suggestions for a comprehensive ADAS systems are highlighted. As this work is intended as a general survey on ADAS, the technical specifications of each system are not discussed in details.
2014 IEEE International Conference on Industrial Technology (ICIT), 2014
This paper describes modeling, attitude estimation, attitude control, and altitude control for He... more This paper describes modeling, attitude estimation, attitude control, and altitude control for Hexarotor micro aerial vehicle (MAV). Hexarotor has high potential to carry more payload and high maneuverability compared to quadrotor. This paper proposes a new approach for attitude estimation in real- time system by using a nonlinear complementary observer based on special orthogonal group of rotation matrices SO(3), rather than conventional extended Kalman filter (EKF), to exploit the near-global convergence property of the observer and reduced computational complexity. The proposed attitude controller is based on an inner-outer loop structure PI+PID (proportional- integral plus proportional-integral-derivative) control method to reduce the overshoot effects, leads to faster response, improve robustness and transient response, whilst the proposed altitude controller is based on classical closed loop PID control system. Simulation results will be presented showing the proposed controller achieves excellent dynamical performance and finally, the experimental results, both in indoor and outdoor flying environment demonstrate the effectiveness of the proposed attitude observer and controller in real flight condition.
The huge developments in the field of magnetorheological (MR) fluid-based devices will have a gre... more The huge developments in the field of magnetorheological (MR) fluid-based devices will have a great influence on the future of mechatronic applications due to the ease of interfacing between electronic controls and the mechanical components that they provide. Among various MR fluid-based devices, an MR valve would be particularly significant for the development of other devices, if it could be successfully achieved. One of the most challenging obstacles to MR valve development is the difficulty of achieving device miniaturization while, at the same time, improving the achievable performance. This study demonstrates a novel design for an MR valve, using the meandering flow path approach in order to increase the effective area so that the MR fluid can be regulated within a small-sized valve. The meandering flow path is formed by combining multiple annular, radial and orifice flow channels. In order to analyze the valve performance, a mathematical model of the proposed MR valve is derived and combined with numerical simulation using the finite element method, with the intention of predicting the achievable pressure drop that can be generated by the valve. The predicted MR valve performances are then experimentally evaluated using an oscillation-disturbed bypass hydraulic cylinder. The simulation results show that the proposed MR valve design could yield substantial pressure drop improvement, which is confirmed by the experiment.