Wheeled mobile robots are popular because of relatively low mechanical complexity and energy consumption. The need of personal mobility supporting personal movement for the aging society is increasing. As mobility needs limited independent power sources, energy management is the key factor to complete tasks. This paper presents a wheeled device with a redundant drive system to continue its motion safely when one of the motors breaks down for some causes. Simulation results show that the proposed method is effective in saving energy approximately by 33 % compared to a conventional one.

This article presents sliding mode–based robust tracking control for a redundant wheeled drive system, which is designed for energy saving and fail safe motion. Wheeled mobile robots are widely used in different applications such as a wheelchair and an automated guided vehicle because of their loading capability, low mechanical complexity, and simple engineering design. In addition, using wheeled mobile robots is an effective way to enhance the quality of life for elderly and disabled people to promote their independence and to extend their activities. Wheeled mobile robots are generally operated using embedded batteries, which determine the operating time. Therefore, saving energy motion is a significant requirement to extend the operation time. The dynamics of a redundant wheeled drive system is described. Distribution control and sliding mode control for wheeled mobile robots are proposed, and its stability is guaranteed based on the Lyapunov stability theory. Finally, the robustness and effectiveness of the proposed method are demonstrated experimentally, providing superior results to conventional state feedback control and robust tracking in the real environment with less energy.

Mobile robots are widely used in many applications, such as transportation, military domain, searching, guidance, rescue, hazard detection, and carpet cleaning. Because mobile robots usually carry limited power sources, such as batteries, energy saving is an important concern. In particular, differential wheeled mobile robots that have two independently movable wheels are popular because of relatively low mechanical complexity to achieve three-dimensional motion on a ground. This article presents a new wheeled device with a redundant drive system which consists of three independently movable actuators and two planetary gears to connect the actuators to two wheels. The proposed system is able to continue its motion safely when one of the motors breaks down for some causes and also able to operate over a longer period of time due to energy saving consumption property. Experimental results show that the proposed method is effective in saving energy approximately by 20.45% for linear motion and 13.05% for circular motion compared to a conventional one

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The main purpose of this paper is to enhance the operation of renewable wind energy conversion (WEC) systems connected to power systems. To achieve this, we consider a linear quadratic Gaussian (LQG) control approach for regulating the eects of a WEC system with doubly fed induction generator (DFIG) on the synchronous generator (SG) rotor speed of the interconnected power system. First, we present the mathematical formulation of the interconnected power system comprises a single synchronous generator and a wind turbine with DFIG connected to an infinite bus bar system through a transmission line. We consider that the system is operated under various loading conditions and parameters variation. Second, a frequency damping oscillation observer is designed via Kalman filtering together with an optimal linear quadratic regulator to mitigate the impacts of the WEC system on the SG rotor speed. The performance of the developed interconnected power system is simulated using a MATLAB/SIMULINK environment to verify the eectiveness of the developed controller. In comparison with previously reported results, the proposed approach can stabilize the interconnected power system within 1.28 s compared to 1.3 s without the DFIG.

The main purpose of this paper is to enhance the operation of renewable wind energy conversion (WEC) systems connected to power systems. To achieve this, we consider a linear quadratic Gaussian (LQG) control approach for regulating the eects of a WEC system with doubly fed induction generator (DFIG) on the synchronous generator (SG) rotor speed of the interconnected power system. First, we present the mathematical formulation of the interconnected power system comprises a single synchronous generator and a wind turbine with DFIG connected to an infinite bus bar system through a transmission line. We consider that the system is operated under various loading conditions and parameters variation. Second, a frequency damping oscillation observer is designed via Kalman filtering together with an optimal linear quadratic regulator to mitigate the impacts of the WEC system on the SG rotor speed. The performance of the developed interconnected power system is simulated using a MATLAB/SIMULINK environment to verify the eectiveness of the developed controller. In comparison with previously reported results, the proposed approach can stabilize the interconnected power system within 1.28 s compared to 1.3 s without the DFIG.

The main purpose of this paper is to enhance the operation of renewable wind energy conversion (WEC) systems connected to power systems. To achieve this, we consider a linear quadratic Gaussian (LQG) control approach for regulating the eects of a WEC system with doubly fed induction generator (DFIG) on the synchronous generator (SG) rotor speed of the interconnected power system. First, we present the mathematical formulation of the interconnected power system comprises a single synchronous generator and a wind turbine with DFIG connected to an infinite bus bar system through a transmission line. We consider that the system is operated under various loading conditions and parameters variation. Second, a frequency damping oscillation observer is designed via Kalman filtering together with an optimal linear quadratic regulator to mitigate the impacts of the WEC system on the SG rotor speed. The performance of the developed interconnected power system is simulated using a MATLAB/SIMULINK environment to verify the eectiveness of the developed controller. In comparison with previously reported results, the proposed approach can stabilize the interconnected power system within 1.28 s compared to 1.3 s without the DFIG.

The present study is concerned with the stability of side slope for the highways lying between two canals, eastern Nag Hamady canal and western side canal at Km(70.8).The canals and highway are located on the right bank of the Nile, and pass through the governorates of Assiut and Sohag. The side slope cracks as well as cracks in the asphalt road usually happen after winter closing period in the left side slope of the road. This is attributed to the difference in water levels between the two neighboring canals and soil weakness. The present study deals with this problem and can be divided into two main parts: • The first part is an experimental work using triaxial test, shear box test, and consolidation test, which are carried out on undisturbed samples to determine physical and mechanical soil properties. • The second part is the numerical investigation using the obtained soil properties from the experimental work. Two computer programs are used from GEOSTUDIO 2004 library. First (SLOPE/W) is used for slope stability analysis by limit equilibrium method. This program deals with slope stability methods such as Ordinary, Bishop, Janbu and Morgenstern- price methods. The second is the stress analysis program (SIGMA/W).This program is based on finite element technique. The MohrCoulomb yield criteria is used to represent soil layers. Study results showed that slopes at the investigated seating sites are unsafe. The numerical simulation with GEOSTUDIO 2004 is powerful to determine the location of the cracks for highway side slope of eastern Nag Hamadey canal, and is in good agreement with the actual observation in the field. Also, proposed practical methods are suggested to improve stability properties for the highway side slope using piles, cut- off wall to obtain factor of safety, greater than 1.5

The present study is concerned with the stability of side slope for the highways lying between two canals, eastern Nag Hamady canal and western side canal at Km(70.8).The canals and highway are located on the right bank of the Nile, and pass through the governorates of Assiut and Sohag. The side slope cracks as well as cracks in the asphalt road usually happen after winter closing period in the left side slope of the road. This is attributed to the difference in water levels between the two neighboring canals and soil weakness. The present study deals with this problem and can be divided into two main parts: • The first part is an experimental work using triaxial test, shear box test, and consolidation test, which are carried out on undisturbed samples to determine physical and mechanical soil properties. • The second part is the numerical investigation using the obtained soil properties from the experimental work. Two computer programs are used from GEOSTUDIO 2004 library. First (SLOPE/W) is used for slope stability analysis by limit equilibrium method. This program deals with slope stability methods such as Ordinary, Bishop, Janbu and Morgenstern- price methods. The second is the stress analysis program (SIGMA/W).This program is based on finite element technique. The MohrCoulomb yield criteria is used to represent soil layers. Study results showed that slopes at the investigated seating sites are unsafe. The numerical simulation with GEOSTUDIO 2004 is powerful to determine the location of the cracks for highway side slope of eastern Nag Hamadey canal, and is in good agreement with the actual observation in the field. Also, proposed practical methods are suggested to improve stability properties for the highway side slope using piles, cut- off wall to obtain factor of safety, greater than 1.5

The present study is concerned with the stability of side slope for the highways lying between two canals, eastern Nag Hamady canal and western side canal at Km(70.8).The canals and highway are located on the right bank of the Nile, and pass through the governorates of Assiut and Sohag. The side slope cracks as well as cracks in the asphalt road usually happen after winter closing period in the left side slope of the road. This is attributed to the difference in water levels between the two neighboring canals and soil weakness. The present study deals with this problem and can be divided into two main parts: • The first part is an experimental work using triaxial test, shear box test, and consolidation test, which are carried out on undisturbed samples to determine physical and mechanical soil properties. • The second part is the numerical investigation using the obtained soil properties from the experimental work. Two computer programs are used from GEOSTUDIO 2004 library. First (SLOPE/W) is used for slope stability analysis by limit equilibrium method. This program deals with slope stability methods such as Ordinary, Bishop, Janbu and Morgenstern- price methods. The second is the stress analysis program (SIGMA/W).This program is based on finite element technique. The MohrCoulomb yield criteria is used to represent soil layers. Study results showed that slopes at the investigated seating sites are unsafe. The numerical simulation with GEOSTUDIO 2004 is powerful to determine the location of the cracks for highway side slope of eastern Nag Hamadey canal, and is in good agreement with the actual observation in the field. Also, proposed practical methods are suggested to improve stability properties for the highway side slope using piles, cut- off wall to obtain factor of safety, greater than 1.5