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Mathematical Modelling of Engineering Problems
In this paper a quarter-vehicle full-scale suspension test rig was designed and manufactured,the ... more In this paper a quarter-vehicle full-scale suspension test rig was designed and manufactured,the suspension is considered semi-active as the electrohydraulic (EH) damper used is fullycontrolled. This gives an indoor-based simulation tool which is important for vehicle testing;.This reduces the cost significantly with accurate results, especially when designing a newsuspension system. The aim of the current work was to build a new quarter-vehicle test rigwith expandable capabilities for diverse design objectives, also may be used for academicpurposes. The control objective was achieved by using dynamic characteristics of theelectrohydraulic (EH) damper to suppress the oscillation of the sprung mass due to roadirregularities. The test rig was constructed using a Genesis G80 (2016) suspension system.Finally, the simulation results demonstrated that the proposed controller used be able toefficiently regulate the chassis vertical oscillation under these irregularities. The experimentalre...
Engineering and Technology Journal
Passive hydraulic dampers are commonly used in the automotive suspension system. Nevertheless, th... more Passive hydraulic dampers are commonly used in the automotive suspension system. Nevertheless, they are suffering from a significant drawback owing to the changing of its characteristics at high-frequency; as a result, decreasing the ride quality due to the increase of the transmitted force, especially at high frequency excitations. The present work developed a semi-active suspension system to solve this problem with its effect. A Skyhook control strategy is used to suppress the positional oscillation of the sprung mass in the presence of road irregularities via the use of the electrohydraulic (EH) damper, as an objective. In order to apply the control strategy used herein, a full-scale quarter-car test platform has been designed and constructed to offer increased testing flexibility at a reasonable cost not found commercially. MATLAB Simulink is applied for modeling the semiactive suspension system. The control strategy using a Sky-hook control was used to enhance the comfort due to the simplicity of this method that can easily be implemented in a real-time embedded application. The control strategy is evaluated for its performance under the road bump excitation. The experimental results were compared with the simulated ones for both passive and semi-active suspension systems, the comparison includes time response analysis of body vertical displacement, and vertical displacement of quarter car structure.
Journal of Engineering, Mar 1, 2018
The present work evaluated the differences in mechanical properties of two athletic prosthetic fe... more The present work evaluated the differences in mechanical properties of two athletic prosthetic feet samples when subjected to impact while running. Two feet samples designated as design A and B were manufactured using layers of different orientations of woven glass fiber reinforced with unsaturated polyester resin as bonding epoxy. The samples’ layers were fabricated with hand lay-up method. A theoretical study was carried out to calculate the mechanical properties of the composite material used in feet manufacturing, then experimental load-deflection test was applied at 0 degree position and 25 degree dorsiflexion feet position and impact test were applied for both feet designs to observe the behavior of the feet under static and impact loading and compare properties like stiffness, efficiency, rigidity, and shock absorption at different drop angles range from 25 degrees to 60 degrees which perform the foot positions while running. The load-deflection test result shows that the maximum deflection of the proposed design B was 32.2 mm at 0° and 38.45mm at 25°. While it was 41mm at 0˚ and 39mm at 25˚ for design A. Impact test result shows that design B foot gives peak load of 128 .7 kg with a peak time of 0.06 sec, while design Afoot gives 125.32 kg peak load with a time of 0.069 sec.
Mathematical Modelling of Engineering Problems
In this paper a quarter-vehicle full-scale suspension test rig was designed and manufactured,the ... more In this paper a quarter-vehicle full-scale suspension test rig was designed and manufactured,the suspension is considered semi-active as the electrohydraulic (EH) damper used is fullycontrolled. This gives an indoor-based simulation tool which is important for vehicle testing;.This reduces the cost significantly with accurate results, especially when designing a newsuspension system. The aim of the current work was to build a new quarter-vehicle test rigwith expandable capabilities for diverse design objectives, also may be used for academicpurposes. The control objective was achieved by using dynamic characteristics of theelectrohydraulic (EH) damper to suppress the oscillation of the sprung mass due to roadirregularities. The test rig was constructed using a Genesis G80 (2016) suspension system.Finally, the simulation results demonstrated that the proposed controller used be able toefficiently regulate the chassis vertical oscillation under these irregularities. The experimentalre...
Engineering and Technology Journal
Passive hydraulic dampers are commonly used in the automotive suspension system. Nevertheless, th... more Passive hydraulic dampers are commonly used in the automotive suspension system. Nevertheless, they are suffering from a significant drawback owing to the changing of its characteristics at high-frequency; as a result, decreasing the ride quality due to the increase of the transmitted force, especially at high frequency excitations. The present work developed a semi-active suspension system to solve this problem with its effect. A Skyhook control strategy is used to suppress the positional oscillation of the sprung mass in the presence of road irregularities via the use of the electrohydraulic (EH) damper, as an objective. In order to apply the control strategy used herein, a full-scale quarter-car test platform has been designed and constructed to offer increased testing flexibility at a reasonable cost not found commercially. MATLAB Simulink is applied for modeling the semiactive suspension system. The control strategy using a Sky-hook control was used to enhance the comfort due to the simplicity of this method that can easily be implemented in a real-time embedded application. The control strategy is evaluated for its performance under the road bump excitation. The experimental results were compared with the simulated ones for both passive and semi-active suspension systems, the comparison includes time response analysis of body vertical displacement, and vertical displacement of quarter car structure.
Journal of Engineering, Mar 1, 2018
The present work evaluated the differences in mechanical properties of two athletic prosthetic fe... more The present work evaluated the differences in mechanical properties of two athletic prosthetic feet samples when subjected to impact while running. Two feet samples designated as design A and B were manufactured using layers of different orientations of woven glass fiber reinforced with unsaturated polyester resin as bonding epoxy. The samples’ layers were fabricated with hand lay-up method. A theoretical study was carried out to calculate the mechanical properties of the composite material used in feet manufacturing, then experimental load-deflection test was applied at 0 degree position and 25 degree dorsiflexion feet position and impact test were applied for both feet designs to observe the behavior of the feet under static and impact loading and compare properties like stiffness, efficiency, rigidity, and shock absorption at different drop angles range from 25 degrees to 60 degrees which perform the foot positions while running. The load-deflection test result shows that the maximum deflection of the proposed design B was 32.2 mm at 0° and 38.45mm at 25°. While it was 41mm at 0˚ and 39mm at 25˚ for design A. Impact test result shows that design B foot gives peak load of 128 .7 kg with a peak time of 0.06 sec, while design Afoot gives 125.32 kg peak load with a time of 0.069 sec.