The Experts below are selected from a list of 61599 Experts worldwide ranked by ideXlab platform
Ujjaval Gupta - One of the best experts on this subject based on the ideXlab platform.
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Modeling of Viscoelastic Electromechanical Behavior in a Soft Dielectric Elastomer Actuator
IEEE Transactions on Robotics, 2017Co-Authors: Guo-ying Gu, Ujjaval GuptaAbstract:Soft dielectric elastomer actuators (DEAs) exhibit interesting muscle-like behavior for the development of soft robots. However, it is challenging to model these soft actuators due to their material nonlinearity, nonlinear electromechanical coupling, and time-dependent viscoelastic behavior. Most recent studies on DEAs focus on issues of Mechanics, Physics, and material science, while much less importance is given to quantitative characterization of DEAs. In this paper, we present a detailed experimental investigation probing the voltage-induced electromechanical response of a soft DEA that is subjected to cyclic loading and propose a general constitutive modeling approach to characterize the time-dependent response, based on the principles of nonequilibrium thermodynamics. In this paper, some of the key observations are found as follows: 1) Creep exhibits the drift phenomenon, and is dominant during the first three cycles. The creep decreases over time and becomes less dominant after the first few cycles; 2) a significant amount of hysteresis is observed during all cycles and it becomes repeatable after the first few cycles; 3) the peak of the displacement is shifted from the peak of the voltage signal and occurs after it. To account for these viscoelastic phenomena, a constitutive model is developed by employing several dissipative nonequilibrium mechanisms. The quantitative comparisons of the experimental and simulation results demonstrate the effectiveness of the developed model. This modeling approach can be useful for control of a viscoelastic DEA and paves the way to emerging applications of soft robots.
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feedforward deformation control of a dielectric elastomer actuator based on a nonlinear dynamic model
Applied Physics Letters, 2015Co-Authors: Ujjaval Gupta, Jian Zhu, Limin Zhu, Xiangyang ZhuAbstract:In the practical applications of actuators, the control of their deformation or driving force is a key issue. Most of recent studies on dielectric elastomer actuators (DEAs) focus on issues of Mechanics, Physics, and material science, whereas less importance is given to the control of these soft actuators. In this paper, we underline the importance of a nonlinear dynamic model as the basis for a feedforward deformation control approach of a rubber-based DEA. Experimental evidence shows the effectiveness of the feedforward controller. The present study confirms that a DEA's trajectory can be finely controlled with a solid nonlinear dynamic model despite the presence of material nonlinearities and electromechanical coupling. The effective control of DEAs may pave the way for extensive emerging applications to soft robots.
Xiangyang Zhu - One of the best experts on this subject based on the ideXlab platform.
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feedforward deformation control of a dielectric elastomer actuator based on a nonlinear dynamic model
Applied Physics Letters, 2015Co-Authors: Ujjaval Gupta, Jian Zhu, Limin Zhu, Xiangyang ZhuAbstract:In the practical applications of actuators, the control of their deformation or driving force is a key issue. Most of recent studies on dielectric elastomer actuators (DEAs) focus on issues of Mechanics, Physics, and material science, whereas less importance is given to the control of these soft actuators. In this paper, we underline the importance of a nonlinear dynamic model as the basis for a feedforward deformation control approach of a rubber-based DEA. Experimental evidence shows the effectiveness of the feedforward controller. The present study confirms that a DEA's trajectory can be finely controlled with a solid nonlinear dynamic model despite the presence of material nonlinearities and electromechanical coupling. The effective control of DEAs may pave the way for extensive emerging applications to soft robots.
Guo-ying Gu - One of the best experts on this subject based on the ideXlab platform.
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Modeling of Viscoelastic Electromechanical Behavior in a Soft Dielectric Elastomer Actuator
IEEE Transactions on Robotics, 2017Co-Authors: Guo-ying Gu, Ujjaval GuptaAbstract:Soft dielectric elastomer actuators (DEAs) exhibit interesting muscle-like behavior for the development of soft robots. However, it is challenging to model these soft actuators due to their material nonlinearity, nonlinear electromechanical coupling, and time-dependent viscoelastic behavior. Most recent studies on DEAs focus on issues of Mechanics, Physics, and material science, while much less importance is given to quantitative characterization of DEAs. In this paper, we present a detailed experimental investigation probing the voltage-induced electromechanical response of a soft DEA that is subjected to cyclic loading and propose a general constitutive modeling approach to characterize the time-dependent response, based on the principles of nonequilibrium thermodynamics. In this paper, some of the key observations are found as follows: 1) Creep exhibits the drift phenomenon, and is dominant during the first three cycles. The creep decreases over time and becomes less dominant after the first few cycles; 2) a significant amount of hysteresis is observed during all cycles and it becomes repeatable after the first few cycles; 3) the peak of the displacement is shifted from the peak of the voltage signal and occurs after it. To account for these viscoelastic phenomena, a constitutive model is developed by employing several dissipative nonequilibrium mechanisms. The quantitative comparisons of the experimental and simulation results demonstrate the effectiveness of the developed model. This modeling approach can be useful for control of a viscoelastic DEA and paves the way to emerging applications of soft robots.
Russell E Ritenour - One of the best experts on this subject based on the ideXlab platform.
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medical Physics and biomedical engineering
Medical Physics, 1999Co-Authors: B H Brown, R H Smallwood, D C Barber, P V Lawford, D R Hose, Russell E RitenourAbstract:BioMechanics. Biofluid Mechanics. Physics of the senses. Biocompatilibity and tissue damage. Ionising radiation dose and exposure: measurements, standards and protection. Radioisotopes and nuclear medicine. Ultrasound. Nonionising electromagnetic radiation: tissue absorption and safety issues. Gaining access to physiological signals. Evoked responses. Image formation. Image production. Mathematical and statistical techniques. Image processing and analysis. Audiology. Electrophysiology. Respiratory function. Pressure measurement. Blood flow measurement. Biomechanical measurements. Ionising radiation: radiotherapy. Safety critical systems and engineering design: cardiac and blood related devices. Bibliography. Index.
Jian Zhu - One of the best experts on this subject based on the ideXlab platform.
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feedforward deformation control of a dielectric elastomer actuator based on a nonlinear dynamic model
Applied Physics Letters, 2015Co-Authors: Ujjaval Gupta, Jian Zhu, Limin Zhu, Xiangyang ZhuAbstract:In the practical applications of actuators, the control of their deformation or driving force is a key issue. Most of recent studies on dielectric elastomer actuators (DEAs) focus on issues of Mechanics, Physics, and material science, whereas less importance is given to the control of these soft actuators. In this paper, we underline the importance of a nonlinear dynamic model as the basis for a feedforward deformation control approach of a rubber-based DEA. Experimental evidence shows the effectiveness of the feedforward controller. The present study confirms that a DEA's trajectory can be finely controlled with a solid nonlinear dynamic model despite the presence of material nonlinearities and electromechanical coupling. The effective control of DEAs may pave the way for extensive emerging applications to soft robots.