The Experts below are selected from a list of 246 Experts worldwide ranked by ideXlab platform

Michael T Tolley - One of the best experts on this subject based on the ideXlab platform.

  • Differential Pressure Control of 3d printed soft fluidic actuators
    Intelligent Robots and Systems, 2017
    Co-Authors: Tom Kalisky, Yueqi Wang, Enjami Shih, Dyla Drotma, Saurabh Jadhav, Eliah Aronoffspence, Michael T Tolley
    Abstract:

    Fluidically actuated soft robots show a great promise for operation in sensitive and unknown environments due to their intrinsic compliance. However, most previous designs use either flow Control systems that are noisy, inefficient, sensitive to leaks, and cannot achieve Differential Pressure (i.e. can only apply either positive or negative Pressures with respect to atmospheric), or closed volume Control systems that are not adaptable and prohibitively expensive. In this paper, we present a modular, low cost volume Control system for Differential Pressure Control of soft actuators. We use this system to actuate three-chamber 3D printed soft robotic modules. For this design, we find a 54% increase in achievable blocked force, and a significant increase in actuator workspace when using Differential Pressure actuation as compared to the use of only Pressure or vacuum. The increased workspace allowed the robot to achieve complex tasks such as writing on a screen with a laser pointer or manipulating fragile objects. Furthermore, we demonstrate a self-healing capability of the combined system by using vacuum to actuate ruptured modules which were no longer responsive to positive Pressure.

  • IROS - Differential Pressure Control of 3D printed soft fluidic actuators
    2017 IEEE RSJ International Conference on Intelligent Robots and Systems (IROS), 2017
    Co-Authors: Tom Kalisky, Yueqi Wang, Saurabh Jadhav, Benjamin Shih, Dylan Drotman, Eliah Aronoff-spencer, Michael T Tolley
    Abstract:

    Fluidically actuated soft robots show a great promise for operation in sensitive and unknown environments due to their intrinsic compliance. However, most previous designs use either flow Control systems that are noisy, inefficient, sensitive to leaks, and cannot achieve Differential Pressure (i.e. can only apply either positive or negative Pressures with respect to atmospheric), or closed volume Control systems that are not adaptable and prohibitively expensive. In this paper, we present a modular, low cost volume Control system for Differential Pressure Control of soft actuators. We use this system to actuate three-chamber 3D printed soft robotic modules. For this design, we find a 54% increase in achievable blocked force, and a significant increase in actuator workspace when using Differential Pressure actuation as compared to the use of only Pressure or vacuum. The increased workspace allowed the robot to achieve complex tasks such as writing on a screen with a laser pointer or manipulating fragile objects. Furthermore, we demonstrate a self-healing capability of the combined system by using vacuum to actuate ruptured modules which were no longer responsive to positive Pressure.

Tom Kalisky - One of the best experts on this subject based on the ideXlab platform.

  • Manipulation of Delicate Objects in Robotics and Medicine: A Design Approach
    2017
    Co-Authors: Tom Kalisky
    Abstract:

    Author(s): Kalisky, Tom | Advisor(s): Tolley, Michael T | Abstract: In this work, I explore two facets of manipulation of delicate objects. First I describe the development of a new closed system for Differential Pressure Control of 3D printed soft fluidic actuators. I further explore the quantitative advancements it promises for soft robotics towards a robotics manipulator capable of safely and efficiently manipulating infant’s fingers. Secondly, we present the development of a biometrics system for vaccinations which requires manipulation and imaging of infants’ fingers. The fingerprinting process could highly benefit from automation solutions for infants’ fingerprint platen induced deformation due to contact. The next aspect of my thesis is the experimental approach for iterative testing in technology design. Starting with the volumetric Control platform developed to enable accurate iterative testing in laboratory settings for experimental characterization of soft actuators with Differential Pressure Control. In this work, I demonstrated a substantial improvement in achievable blocked force, and a significant increase in actuator workspace when using Differential Pressure actuation as compared to the use of only Pressure or vacuum. The increased workspace allowed the robot to achieve complex tasks towards manipulation of fragile objects. Furthermore, I demonstrate a self-healing capability of the combined system for improved soft robotics robustness. Then I follow with an approach for human-centered design with iterative prototyping where experiments can only be performed in situ with live infant subjects. This separation between the design and experiments yields a very challenging progress evaluation and required a unique design iteration methodology. With the resulted fingerprints images from the two leading devices, I demonstrated a higher reliability for high quality infants’ fingerprints using non-contact imaging over contact in the goal of developing a reliable biometrics identification system of infants for vaccination.

  • Differential Pressure Control of 3d printed soft fluidic actuators
    Intelligent Robots and Systems, 2017
    Co-Authors: Tom Kalisky, Yueqi Wang, Enjami Shih, Dyla Drotma, Saurabh Jadhav, Eliah Aronoffspence, Michael T Tolley
    Abstract:

    Fluidically actuated soft robots show a great promise for operation in sensitive and unknown environments due to their intrinsic compliance. However, most previous designs use either flow Control systems that are noisy, inefficient, sensitive to leaks, and cannot achieve Differential Pressure (i.e. can only apply either positive or negative Pressures with respect to atmospheric), or closed volume Control systems that are not adaptable and prohibitively expensive. In this paper, we present a modular, low cost volume Control system for Differential Pressure Control of soft actuators. We use this system to actuate three-chamber 3D printed soft robotic modules. For this design, we find a 54% increase in achievable blocked force, and a significant increase in actuator workspace when using Differential Pressure actuation as compared to the use of only Pressure or vacuum. The increased workspace allowed the robot to achieve complex tasks such as writing on a screen with a laser pointer or manipulating fragile objects. Furthermore, we demonstrate a self-healing capability of the combined system by using vacuum to actuate ruptured modules which were no longer responsive to positive Pressure.

  • IROS - Differential Pressure Control of 3D printed soft fluidic actuators
    2017 IEEE RSJ International Conference on Intelligent Robots and Systems (IROS), 2017
    Co-Authors: Tom Kalisky, Yueqi Wang, Saurabh Jadhav, Benjamin Shih, Dylan Drotman, Eliah Aronoff-spencer, Michael T Tolley
    Abstract:

    Fluidically actuated soft robots show a great promise for operation in sensitive and unknown environments due to their intrinsic compliance. However, most previous designs use either flow Control systems that are noisy, inefficient, sensitive to leaks, and cannot achieve Differential Pressure (i.e. can only apply either positive or negative Pressures with respect to atmospheric), or closed volume Control systems that are not adaptable and prohibitively expensive. In this paper, we present a modular, low cost volume Control system for Differential Pressure Control of soft actuators. We use this system to actuate three-chamber 3D printed soft robotic modules. For this design, we find a 54% increase in achievable blocked force, and a significant increase in actuator workspace when using Differential Pressure actuation as compared to the use of only Pressure or vacuum. The increased workspace allowed the robot to achieve complex tasks such as writing on a screen with a laser pointer or manipulating fragile objects. Furthermore, we demonstrate a self-healing capability of the combined system by using vacuum to actuate ruptured modules which were no longer responsive to positive Pressure.

Jili Zhang - One of the best experts on this subject based on the ideXlab platform.

  • An optimal Control method for discrete variable outdoor air volume setpoint determination in variable air volume systems
    Building and Environment, 2020
    Co-Authors: Tianyi Zhao, Pengmin Hua, Wuhe Dai, Jili Zhang
    Abstract:

    Abstract In multi-zone variable outdoor air (OA) volume air-conditioning systems, there is often a mismatch between OA volume flow supply and demand, because variable air volume (VAV) systems exhibit nonlinear, multivariable, and long delay characteristics. Traditional methods ensure indoor air quality (IAQ) by increasing OA volume flow, which leads to a waste of OA flow energy. To address this problem, an optimal Control method for determining discrete variable OA volume flow setpoints, based on Differential Pressure Control, is proposed in this study. In this method, changes in indoor CO2 concentration and the total air volume flow demand of terminals are regarded as constraints of OA volume flow setpoints. A Proportional-Integral (PI) calculation method and trial-and-error method are used to discretize continuous OA volume flow setpoints to increase system stability. Two types of experiments were conducted to compare the characteristics of the two discrete OA volume flow setpoint determining methods, and to verify the feasibility of our new approach. The results show that the OA volume flow Control loop can be well fitted with other Control loops of VAV systems, and ensure OA volume flow demand for a target area. The proposed method provides greater energy savings than maximum OA ratio Control strategy (7%–22%) and typical on-demand ventilation method (6.1%), and better Control performance than continuous OA volume flow setpoints Control system. The PI calculation method is suitable for conditions with high IAQ requirements, while the trial-and-error method can be used for comfort air-conditioning systems to adjust the indoor environment.

C L Hwang - One of the best experts on this subject based on the ideXlab platform.

  • sliding mode Control using time varying switching gain and boundary layer for electrohydraulic position and Differential Pressure Control
    IEE Proceedings - Control Theory and Applications, 1996
    Co-Authors: C L Hwang
    Abstract:

    It is well known that the sliding mode Control possesses the following advantages: fast response, less sensitive to uncertainties, and easy implementation. However, traditional sliding mode Control often results in a chattering Control input because of its discontinuous switching Control. The chattering Control input has some drawbacks: easy damage of mechanism and excitation of unmodelled dynamics. Although the boundary layer method can attenuate the degree of high-frequency Control input, its stability is guaranteed only outside the boundary layer, and its asymptotic tracking often cannot be achieved if the boundary layer is insufficiently small. Furthermore, a fixed switching gain often gives too much energy for the purpose of trajectory tracking. Owing to these disadvantages of traditional sliding mode Control (i.e. fixed switching gain and fixed boundary layer), one sufficient condition for a time-varying switching gain and a time-varying boundary layer, which is the memoryless function of the tracking error, is achieved to reduce the Control effort in magnitude and frequency, and to ensure asymptotic tracking. To verify the effectiveness of the proposed Control, computer simulations for the combination of weighted electrohydraulic position and Differential Pressure Control are demonstrated.

Tianyi Zhao - One of the best experts on this subject based on the ideXlab platform.

  • An optimal Control method for discrete variable outdoor air volume setpoint determination in variable air volume systems
    Building and Environment, 2020
    Co-Authors: Tianyi Zhao, Pengmin Hua, Wuhe Dai, Jili Zhang
    Abstract:

    Abstract In multi-zone variable outdoor air (OA) volume air-conditioning systems, there is often a mismatch between OA volume flow supply and demand, because variable air volume (VAV) systems exhibit nonlinear, multivariable, and long delay characteristics. Traditional methods ensure indoor air quality (IAQ) by increasing OA volume flow, which leads to a waste of OA flow energy. To address this problem, an optimal Control method for determining discrete variable OA volume flow setpoints, based on Differential Pressure Control, is proposed in this study. In this method, changes in indoor CO2 concentration and the total air volume flow demand of terminals are regarded as constraints of OA volume flow setpoints. A Proportional-Integral (PI) calculation method and trial-and-error method are used to discretize continuous OA volume flow setpoints to increase system stability. Two types of experiments were conducted to compare the characteristics of the two discrete OA volume flow setpoint determining methods, and to verify the feasibility of our new approach. The results show that the OA volume flow Control loop can be well fitted with other Control loops of VAV systems, and ensure OA volume flow demand for a target area. The proposed method provides greater energy savings than maximum OA ratio Control strategy (7%–22%) and typical on-demand ventilation method (6.1%), and better Control performance than continuous OA volume flow setpoints Control system. The PI calculation method is suitable for conditions with high IAQ requirements, while the trial-and-error method can be used for comfort air-conditioning systems to adjust the indoor environment.