Ibrahim M. H. Sanhoury

Switching between formations for multiple mobile robots via synchronous controller

This paper proposes a new synchronous control law to perform multiple mobile robots trajectory tracking while maintaining time-varying formations. Each robot is controlled to track its desired trajectory while synchronizing its motion with the two nearby robots to maintain the desired time-varying formation. The dynamic model of the wheeled mobile robot (WMR) is derived, so as, it can be divided into a translational and rotational model, in order to control each model separately. Then, a synchronous controller for each robots translation is proposed to guarantee the asymptotic stability of both position and synchronization errors. Also, an orientation controller is proposed to ensure that the robot is always oriented towards its desired position. The simulation results verify the effectiveness of the proposed synchronous controller in the formation control tasks.

Trajectory tracking of steering system mobile robot

In this paper, the kinematic model of nonholonomic differential wheeled mobile robot steering system is established. Based on the model, a nonlinear feedback path tracking controller is proposed, which causes the closed loop system state equation for the robot to have equilibrium condition at the origin. Lyapunov candidate function is used to prove that the closed loop system is asymptotically stable at origin. Simulation results verify the usefulness of the tracking control approach.

Formation control of multiple mobile robots utilising synchronisation approach

In this paper, a new synchronous control rule is proposed for multiple mobile robot trajectories tracking while maintaining time varying formation. Each robot is controlled to track the desired path while its motion is synchronised with the two neighbouring robots to perform and maintain a desired time-varying formation. The dynamic model of the wheeled mobile robot is derived and divided into a translational and rotational dynamic model. A new synchronous translational controller is proposed to guarantee the asymptotic stability of both position and synchronisation errors. A simulation result of 20 robots has been conducted to validate the effectiveness of the proposed synchronous controller in the time-varying formation tasks.

Determining subject distance based on face size

This paper presents a novel method that can estimate the distance of a person up to 6 meters away. The proposed approach is based on face images extracted from a video of a monocular camera through the use of the Viola-Jones approach of OpenCV to detect the faces. The results of the experiments show the practicality of this approach in calculating the distances of the subjects in the cameras view.

Formations Strategies for Obstacle Avoidance with Multi Agent Robotic System

In this paper we aim to introduce the multi agent robotic systems (MARS) to make a good understanding of how it works. Multi-agent systems consisting lot type class of mobile which can communicate between each other and maintain a desired formation. Task become more challenging when group of multi agent change the formation when facing the obstacles. Three non-holonomic robots - “MYbots” will performs some demonstrations which first experiment to maintaining triangular formation while moving and second experiment focus on two type leader face obstacle and follow face obstacle avoidance. Method that used in this research is a leader follower method. Follower MYbot will follow the path commanded by the Leader MYbot to avoid obstacle.

A time-varying saturated synchronous formation controller for nonholonomic mobile robots

In this paper, a new saturated synchronous controller is proposed for multiple nonholonomic wheeled mobile robots to perform a time-varying formation task. Each robot is controlled to track its desired trajectory, while synchronized its motion with the two neighboring robots. A novel dynamic model of the wheeled mobile robot is derived based on Lagrange method. The Lagrange multipliers of the robot are determined based on the input torques and the robots velocities. The dynamic model is divided into translational and rotational model. A saturated synchronous translational controller is proposed to guarantee the asymptotic stability of both position and synchronization errors. A rotational controller is developed such that each robot always oriented towards its desired position. A simulation results verified the efficiency of the proposed saturated synchronous controller in the formation tasks.

Time-varying formation control for nonholonomic wheeled mobile robots via synchronization

In this paper, a new synchronous control law is proposed for multiple nonholonomic wheeled mobile robots (WMR) to perform a time-varying formation task. Each robot is controlled to track its desired trajectory, while synchronized its motion with the two adjoining robots. A novel dynamic model of the WMR is derived based on Lagrange method. The Lagrange multiplier of the WMR is determined based on the input torques and the robots velocities. The dynamic model has been divided into translational and rotational model. A synchronous translational controller is proposed to guarantee the asymptotic stability of both position and synchronization errors. A rotational controller is designed such that the robot always facing its desired position. A simulation results verified the effectiveness of the proposed synchronous controller in the formation tasks.

Stable Dynamic Walking Gait Humanoid

This research introduces the formulation of humanoid robot walking gait in dynamic form. The formula is generated based on three point location at each ankle and at the hip of the robot. Then the inverse kinematic geometric method was used to locate the entire joints angle trajectory for each link on the biped leg. The robot foot was equipped with the force sensor to determine the Zero Moment Point and the Centre of pressure of the robot foot during the walking. The robot was tested with the three variations of walking gait with different speed.

Implementation of Multi Robot Communication via Bluetooth

In multi robot system where two or more robot will be working together to complete a task given, it is fundamental to have a good communication between robots. This paper will discuss communication strategy by providing Personal Area Network (PAN) using Bluetooth method in multi robot area. Bluetooth is a suitable communication between mobile robots because low cost, low power consumption and communication range between 10m to 100m. This network is purpose to able to support real time control. Another advantage is the robot will able to communicate through the wall or obstacle. Bluetooth Protocol Stack and mobile robot control architecture is implemented on a single microcontroller chip. Result from the experiments show that the mobile robot named BlueBot, with programmed microcontroller able to perform a Bluetooth PAN and communicate with each other. One of the objectives of the project is to design and build three autonomous mobile robots which can establish PAN automatically via Bluetooth transceiver for wireless communication (hardware and software).