The Experts below are selected from a list of 198 Experts worldwide ranked by ideXlab platform

Hoyin Chan - One of the best experts on this subject based on the ideXlab platform.

  • Robust control of dielectric elastomer Diaphragm Actuator for human pulse signal tracking
    Smart Materials and Structures, 2017
    Co-Authors: Zhihang Ye, Ramazan Asmatulu, Zheng Chen, Hoyin Chan
    Abstract:

    Human pulse signal tracking is an emerging technology that is needed in traditional Chinese medicine. However, soft actuation with multi-frequency tracking capability is needed for tracking human pulse signal. Dielectric elastomer (DE) is one type of soft actuating that has great potential in human pulse signal tracking. In this paper, a DE Diaphragm Actuator was designed and fabricated to track human pulse pressure signal. A physics-based and control-oriented model has been developed to capture the dynamic behavior of DE Diaphragm Actuator. Using the physical model, an H-infinity robust control was designed for the Actuator to reject high-frequency sensing noises and disturbances. The robust control was then implemented in real-time to track a multi-frequency signal, which verified the tracking capability and robustness of the control system. In the human pulse signal tracking test, a human pulse signal was measured at the City University of Hong Kong and then was tracked using DE Actuator at Wichita State University in the US. Experimental results have verified that the DE Actuator with its robust control is capable of tracking human pulse signal.

  • robust control of dielectric elastomer Diaphragm Actuator for replicating human pulse
    Conference on Automation Science and Engineering, 2016
    Co-Authors: Zheng Chen, Ka Wai Kong, Hoyin Chan
    Abstract:

    Human pulse replication is an emerging technology that enables telediagnosis in traditional Chinese medicine. However, soft actuation with multi-frequency tracking capability is in great need for replicating human pulse signal. Dielectric elastomer (DE) is one type of soft actuating materials, which shows great potential in human pulse replication. In this paper, we developed a model-based robust control for a DE Diaphragm Actuator to track human pulse signal. The DE Diaphragm Actuator is designed and fabricated. An empirical model of the DE Actuator is developed to build a black-box model based on the experimental data. Based on the empirical model, an H-infinity robust control is designed to reject high-frequency sensing noises and disturbances. The robust control was then implemented in real-time to track human pulse signal. A human pulse signal was measured at the City University of Hong Kong and replicated at Wichita State University in US. Experimental data has verified that the DE Actuator with its robust control was capable of replicating human pulse signal for telediagnosis.

  • CASE - Robust control of dielectric elastomer Diaphragm Actuator for replicating human pulse
    2016 IEEE International Conference on Automation Science and Engineering (CASE), 2016
    Co-Authors: Zheng Chen, Ka Wai Kong, Hoyin Chan
    Abstract:

    Human pulse replication is an emerging technology that enables telediagnosis in traditional Chinese medicine. However, soft actuation with multi-frequency tracking capability is in great need for replicating human pulse signal. Dielectric elastomer (DE) is one type of soft actuating materials, which shows great potential in human pulse replication. In this paper, we developed a model-based robust control for a DE Diaphragm Actuator to track human pulse signal. The DE Diaphragm Actuator is designed and fabricated. An empirical model of the DE Actuator is developed to build a black-box model based on the experimental data. Based on the empirical model, an H-infinity robust control is designed to reject high-frequency sensing noises and disturbances. The robust control was then implemented in real-time to track human pulse signal. A human pulse signal was measured at the City University of Hong Kong and replicated at Wichita State University in US. Experimental data has verified that the DE Actuator with its robust control was capable of replicating human pulse signal for telediagnosis.

Zheng Chen - One of the best experts on this subject based on the ideXlab platform.

  • Modeling and Control of a 2-DOF Dielectric Elastomer Diaphragm Actuator
    IEEE-ASME Transactions on Mechatronics, 2019
    Co-Authors: Zheng Chen
    Abstract:

    In optical systems, reflectors are commonly used for directing light beams to desired directions. In this paper, a dielectric elastomer (DE) based optical manipulator is developed for two degrees-of-freedom (2-DOF) manipulation. The DE manipulator consists of a Diaphragm with four segments that are controlled in two pairs, thus generating 2-DOF tilting motions. Due to its soft and gear-less moving structure, the DE manipulator is lightweight and naturally resistant to mechanical vibrations. Moreover, its nonelectromagnetic-driven mechanism allows it to work under the environments that are exposed to strong magnetic fields. To design a robust control strategy for the Actuator, a physics-based and control-oriented nonlinear model is then developed and linearized around the equilibrium point. A feedback control system, which consists of two H-infinity controls, is developed to track two tilting angles along two axes. Experimental results have shown that this manipulator is able to track 0.3° 2-DOF tilting angle with 0.03° accuracy.

  • Robust control of dielectric elastomer Diaphragm Actuator for human pulse signal tracking
    Smart Materials and Structures, 2017
    Co-Authors: Zhihang Ye, Ramazan Asmatulu, Zheng Chen, Hoyin Chan
    Abstract:

    Human pulse signal tracking is an emerging technology that is needed in traditional Chinese medicine. However, soft actuation with multi-frequency tracking capability is needed for tracking human pulse signal. Dielectric elastomer (DE) is one type of soft actuating that has great potential in human pulse signal tracking. In this paper, a DE Diaphragm Actuator was designed and fabricated to track human pulse pressure signal. A physics-based and control-oriented model has been developed to capture the dynamic behavior of DE Diaphragm Actuator. Using the physical model, an H-infinity robust control was designed for the Actuator to reject high-frequency sensing noises and disturbances. The robust control was then implemented in real-time to track a multi-frequency signal, which verified the tracking capability and robustness of the control system. In the human pulse signal tracking test, a human pulse signal was measured at the City University of Hong Kong and then was tracked using DE Actuator at Wichita State University in the US. Experimental results have verified that the DE Actuator with its robust control is capable of tracking human pulse signal.

  • CASE - Robust control of dielectric elastomer Diaphragm Actuator for replicating human pulse
    2016 IEEE International Conference on Automation Science and Engineering (CASE), 2016
    Co-Authors: Zheng Chen, Ka Wai Kong, Hoyin Chan
    Abstract:

    Human pulse replication is an emerging technology that enables telediagnosis in traditional Chinese medicine. However, soft actuation with multi-frequency tracking capability is in great need for replicating human pulse signal. Dielectric elastomer (DE) is one type of soft actuating materials, which shows great potential in human pulse replication. In this paper, we developed a model-based robust control for a DE Diaphragm Actuator to track human pulse signal. The DE Diaphragm Actuator is designed and fabricated. An empirical model of the DE Actuator is developed to build a black-box model based on the experimental data. Based on the empirical model, an H-infinity robust control is designed to reject high-frequency sensing noises and disturbances. The robust control was then implemented in real-time to track human pulse signal. A human pulse signal was measured at the City University of Hong Kong and replicated at Wichita State University in US. Experimental data has verified that the DE Actuator with its robust control was capable of replicating human pulse signal for telediagnosis.

  • robust control of dielectric elastomer Diaphragm Actuator for replicating human pulse
    Conference on Automation Science and Engineering, 2016
    Co-Authors: Zheng Chen, Ka Wai Kong, Hoyin Chan
    Abstract:

    Human pulse replication is an emerging technology that enables telediagnosis in traditional Chinese medicine. However, soft actuation with multi-frequency tracking capability is in great need for replicating human pulse signal. Dielectric elastomer (DE) is one type of soft actuating materials, which shows great potential in human pulse replication. In this paper, we developed a model-based robust control for a DE Diaphragm Actuator to track human pulse signal. The DE Diaphragm Actuator is designed and fabricated. An empirical model of the DE Actuator is developed to build a black-box model based on the experimental data. Based on the empirical model, an H-infinity robust control is designed to reject high-frequency sensing noises and disturbances. The robust control was then implemented in real-time to track human pulse signal. A human pulse signal was measured at the City University of Hong Kong and replicated at Wichita State University in US. Experimental data has verified that the DE Actuator with its robust control was capable of replicating human pulse signal for telediagnosis.

  • Artificial muscles of dielectric elastomers attached to artificial tendons of functionalized carbon fibers
    Proceedings of SPIE, 2014
    Co-Authors: Zhihang Ye, Shahnewaz Sabit Faisal, Ramazan Asmatulu, Zheng Chen
    Abstract:

    Dielectric elastomers are soft actuation materials with promising applications in robotics and biomedical de- vices. In this paper, a bio-inspired artificial muscle Actuator with artificial tendons is developed for robotic arm applications. The Actuator uses dielectric elastomer as artificial muscle and functionalized carbon fibers as artificial tendons. A VHB 4910 tape is used as the dielectric elastomer and PDMS is used as the bonding material to mechanically connect the carbon fibers to the elastomer. Carbon fibers are highly popular for their high electrical conductivities, mechanical strengths, and bio-compatibilities. After the acid treatments for the functionalization of carbon fibers (500 nm - 10 μm), one end of carbon fibers is spread into the PDMS material, which provides enough bonding strength with other dielectric elastomers, while the other end is connected to a DC power supply. To characterize the actuation capability of the dielectric elastomer and electrical conductivity of carbon fibers, a Diaphragm Actuator is fabricated, where the carbon fibers are connected to the Actuator. To test the mechanical bonding between PDMS and carbon fibers, specimens of PDMS bonded with carbon fibers are fabricated. Experiments have been conducted to verify the actuation capability of the dielectric elastomer and mechanical bonding of PDMS with carbon fibers. The energy efficiency of the dielectric elastomer increases as the load increases, which can reach above 50%. The mechanical bonding is strong enough for robotic arm applications.

Ka Wai Kong - One of the best experts on this subject based on the ideXlab platform.

  • robust control of dielectric elastomer Diaphragm Actuator for replicating human pulse
    Conference on Automation Science and Engineering, 2016
    Co-Authors: Zheng Chen, Ka Wai Kong, Hoyin Chan
    Abstract:

    Human pulse replication is an emerging technology that enables telediagnosis in traditional Chinese medicine. However, soft actuation with multi-frequency tracking capability is in great need for replicating human pulse signal. Dielectric elastomer (DE) is one type of soft actuating materials, which shows great potential in human pulse replication. In this paper, we developed a model-based robust control for a DE Diaphragm Actuator to track human pulse signal. The DE Diaphragm Actuator is designed and fabricated. An empirical model of the DE Actuator is developed to build a black-box model based on the experimental data. Based on the empirical model, an H-infinity robust control is designed to reject high-frequency sensing noises and disturbances. The robust control was then implemented in real-time to track human pulse signal. A human pulse signal was measured at the City University of Hong Kong and replicated at Wichita State University in US. Experimental data has verified that the DE Actuator with its robust control was capable of replicating human pulse signal for telediagnosis.

  • CASE - Robust control of dielectric elastomer Diaphragm Actuator for replicating human pulse
    2016 IEEE International Conference on Automation Science and Engineering (CASE), 2016
    Co-Authors: Zheng Chen, Ka Wai Kong, Hoyin Chan
    Abstract:

    Human pulse replication is an emerging technology that enables telediagnosis in traditional Chinese medicine. However, soft actuation with multi-frequency tracking capability is in great need for replicating human pulse signal. Dielectric elastomer (DE) is one type of soft actuating materials, which shows great potential in human pulse replication. In this paper, we developed a model-based robust control for a DE Diaphragm Actuator to track human pulse signal. The DE Diaphragm Actuator is designed and fabricated. An empirical model of the DE Actuator is developed to build a black-box model based on the experimental data. Based on the empirical model, an H-infinity robust control is designed to reject high-frequency sensing noises and disturbances. The robust control was then implemented in real-time to track human pulse signal. A human pulse signal was measured at the City University of Hong Kong and replicated at Wichita State University in US. Experimental data has verified that the DE Actuator with its robust control was capable of replicating human pulse signal for telediagnosis.

William W. Clark - One of the best experts on this subject based on the ideXlab platform.

  • Finite element analysis of unimorph rectangular piezoelectric Diaphragm Actuators with experimental verification
    Smart Materials and Structures, 2012
    Co-Authors: Rika M. Wright, Ryan R. Knight, William W. Clark
    Abstract:

    This paper presents a study in which the behavior of clamped unimorph rectangular piezoelectric Diaphragms is analyzed and the importance of electrode patterning for enhancement of static displacement is examined. Previous work showed that by regrouping the electrode pattern of a clamped-circular Diaphragm Actuator the maximum static deflection increased by nearly an order of magnitude in response to an electric field. To extend this concept and determine the effects of electrode patterns and the shape of the piezoelectric layer on the Actuator’s static displacement the rectangular Diaphragm Actuators are analyzed by the finite element method. Experiments for the three different cases of rectangular Actuators are also carried out to validate the models. It was found that the measured static deflections for the clamped rectangular Actuators are in accordance with analytical results and regrouping the electrode pattern on a rectangular Actuator can increase deflection by an order of magnitude, and subsequently volumetric displacement, by over four times compared to the unmodified (fully covered) case.

  • Behavior of Unimorph Rectangular Piezoelectric Diaphragm Actuators
    Smart Structures and Materials 2006: Smart Structures and Integrated Systems, 2006
    Co-Authors: Brad Boyerinas, William W. Clark
    Abstract:

    ABSTRACT This paper presents a study in which clamped unimorph rect angular piezoelectric Diaphragms are analyzed to determine the importance of electrode patterning. There has been a gr eat deal of interest in getti ng increased deflection out of smaller piezoelectric devices with lower input power. In pr evious work, it has been shown that a clamped circular Diaphragm can generate much increased deflection in response to an elect ric loading when the electrode has a “regrouped” pattern. Regrouping refers to the process of segmenting the electrodes into regions that are electrically disconnected so that the corresponding polarity can be set in opposite directions. The re ctangular Diaphragm Actuator is studied in this paper to determine the effects of electr ode patterns and the shape of the piezoelectric layer on the Actuator’s static displacement. From the analytical results, it is shown that regrouping the electrode pattern on a rectangular Actuator can increase deflection, and subseq uently volumetric displacemen t, by many times. Keywords: Modeling, Rectangular Diaphragm Actuator, E dge conditions, Piezoelectric, Electrode pattern

  • Effect of electrode pattern on the performance of unimorph piezoelectric Diaphragm Actuators
    Smart Structures and Materials 2005: Smart Structures and Integrated Systems, 2005
    Co-Authors: Rika Wright, William W. Clark
    Abstract:

    This paper presents a study in which clamped unimorph piezoelectric Diaphragms are tested to determine the importance of the pattern of the electrodes that supply the driving charge to the Actuator. In previous work, it has been shown that such a Diaphragm, when used as an energy harvesting device, can generate a much increased charge in response to an applied pressure when the electrode has a “regrouped” pattern. Regrouping refers to the process of segmenting the electrodes into regions that are electrically disconnected and then reconnecting those regions such that some have reversed polarity. The circular Diaphragm Actuator studied in this paper works somewhat the opposite of an energy harvester. That is, applied charge is used to generate Diaphragm deflection as opposed to applied pressure generating charge. Four unimorph Diaphragm Actuators, with different electrode patterns, were tested in this work. According to analytical and experimental results, it is shown that a factor of seven increase in Diaphragm deflection can be obtained with regrouping.

Takayuki Shibata - One of the best experts on this subject based on the ideXlab platform.

  • micropump with tini shape memory Diaphragm Actuator
    Journal of The Surface Finishing Society of Japan, 2005
    Co-Authors: Eiji Makino, Takayuki Shibata
    Abstract:

    We fabricated a micropump with a circular Actuator of shape memory alloy (SMA) Diaphragm. The Actuator consisted of a TiNi Diaphragm of 5mm in diameter and 6μm in thickness, and a glass cap. This was fabricated through a process sequence of Si isotropic etching, flash evaporation of the TiNi thin film, annealing for shape memorization, removing of the undesired Si layer by reactive ion etching, and anodic bonding of the glass cap to the Diaphragm structure. The fabricated Actuator gave about 90μm displacement at the center of the Diaphragm under a bias pressure of 200kPa. The SMA micropump, which was completed by gluing the Si check valve with a cantilever valve flap to the Actuator, gave a pumping rate of 3-15μL/min at heating energy of 3-9 J under a bias pressure of 200kPa and at zero back pressure. Experimental data indicate that the fabricated SMA Diaphragm is acceptable as an Actuator of a micropump, while the fabricated valve structure is insufficient as a check valve for high pressure application due to a leak problem.

  • Dynamic actuation properties of TiNi shape memory Diaphragm
    Sensors and Actuators A-physical, 2000
    Co-Authors: Eiji Makino, Takashi Mitsuya, Takayuki Shibata
    Abstract:

    Abstract In order to realize a micropump with a shape memory alloy (SMA) Diaphragm Actuator, TiNi thin film of about 7 μm in thickness was deposited by flash evaporation and its dynamic deformation–shape recovery properties were studied using a bulge test. The TiNi Diaphragm was deformed by applying a gas pressure of 200 kPa, heated resistively to recover its initial flat shape, and then air-cooled to achieve deformation once again. During this thermal cycle, temperature and deflection of the Diaphragm were monitored at its center. In order to monitor temperature, we fabricated a Cu–Ni micro thermocouple on the Diaphragm by conventional evaporation. When the Diaphragm was heated, shape recovery occurred at about 60°C. This continued after the temperature for termination of reverse martensitic transformation, Af (about 70°C), had been reached. Moreover, when the Diaphragm was air-cooled, redeformation began even at temperatures higher than that for the commencement of martensitic transformation, Ms (about 60°C). From a FEM simulation and temperature measurements taken using thermography, these results could be explained by the temperature gradient formed in the Diaphragm due to thermal conduction. When heating rate was increased, time required to complete shape recovery decreased and maximum displacement for shape recovery increased. This could also be explained in terms of the temperature gradient.