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All Outputs (17)

A robotic test rig for performance assessment of prosthetic joints (2022)
Journal Article
Etoundi, A. C., Dobner, A., Agrawal, S., Semasinghe, C. L., Georgilas, I., & Jafari, A. (2022). A robotic test rig for performance assessment of prosthetic joints. Frontiers in Robotics and AI, 8, Article 613579. https://doi.org/10.3389/frobt.2021.613579

Movement within the human body is made possible by joints connecting two or more elements of the musculoskeletal system. Losing one or more of these connections can seriously limit mobility, which in turn can lead to depression and other mental issue... Read More about A robotic test rig for performance assessment of prosthetic joints.

Virtual inertia as an energy dissipation element for haptic interfaces (2022)
Journal Article
Choi, H., Kim, N. G., Jafari, A., Singh, H., & Ryu, J. H. (2022). Virtual inertia as an energy dissipation element for haptic interfaces. IEEE Robotics and Automation Letters, 7(2), 2708-2715. https://doi.org/10.1109/LRA.2022.3144492

Adding virtual damping to dissipate energy has been a major tool for designing stable haptic interfaces in most passivity-based approaches. However, virtual damping is known to dissipate a limited amount of energy. It even generates energy during hig... Read More about Virtual inertia as an energy dissipation element for haptic interfaces.

Bio-inspired knee joint: Trends in the hardware systems development (2021)
Journal Article
Etoundi, A. C., Semasinghe, C. L., Agrawal, S., Dobner, A., & Jafari, A. (2021). Bio-inspired knee joint: Trends in the hardware systems development. Frontiers in Robotics and AI, 8, https://doi.org/10.3389/frobt.2021.613574

The knee joint is a complex structure that plays a significant role in the human lower limb for locomotion activities in daily living. However, we are still not quite there yet where we can replicate the functions of the knee bones and the attached l... Read More about Bio-inspired knee joint: Trends in the hardware systems development.

Multilateral teleoperation over communication time delay using the time-domain passivity approach (2019)
Journal Article
Ryu, J., Ha-Van, Q., & Jafari, A. (2020). Multilateral teleoperation over communication time delay using the time-domain passivity approach. IEEE Transactions on Control Systems Technology, 28(6), 2705 - 2712. https://doi.org/10.1109/TCST.2019.2948126

A general framework to stabilize multilateral teleoperation system over a communication time delay based on the well-known time-domain passivity approach (TDPA) is proposed. The uniqueness of this framework is that it is independent of the amount of... Read More about Multilateral teleoperation over communication time delay using the time-domain passivity approach.

Enhancing the rate-hardness of haptic interaction: Successive force augmentation approach (2019)
Journal Article
Singh, H., Janetzko, D., Jafari, A., Weber, B., Lee, C. I., & Ryu, J. H. (2020). Enhancing the rate-hardness of haptic interaction: Successive force augmentation approach. IEEE Transactions on Industrial Electronics, 67(1), 809-819. https://doi.org/10.1109/TIE.2019.2918500

© 1982-2012 IEEE. There have been numerous approaches that have been proposed to enlarge the impedance range of haptic interaction while maintaining stability. However, enhancing the rate-hardness of haptic interaction while maintaining stability is... Read More about Enhancing the rate-hardness of haptic interaction: Successive force augmentation approach.

Enhancing the Command-Following Bandwidth for Transparent Bilateral Teleoperation (2018)
Journal Article
Singh, H., Jafari, A., Ryu, J. H., & Peer, A. (2018). Enhancing the Command-Following Bandwidth for Transparent Bilateral Teleoperation. Proceedings of the ... IEEE/RSJ International Conference on Intelligent Robots and Systems. IEEE/RSJ International Conference on Intelligent Robots and Systems, 4972-4979. https://doi.org/10.1109/IROS.2018.8593866

© 2018 IEEE. Enhancing transparency of a teleoperation system by increasing the command-following bandwidth has not received lots of attention so far. This is considered a challenging task since in a teleoperation system the command-following bandwid... Read More about Enhancing the Command-Following Bandwidth for Transparent Bilateral Teleoperation.

A conceptual exoskeleton shoulder design for the assistance of upper limb movement (2018)
Journal Article
Perez, C. N., Georgilas, I., Etoundi, A., Chong, J., & Jafari, A. (2018). A conceptual exoskeleton shoulder design for the assistance of upper limb movement. Lecture Notes in Artificial Intelligence, 10965 LNAI, 291-302. https://doi.org/10.1007/978-3-319-96728-8_25

© Springer International Publishing AG, part of Springer Nature 2018. There is an increased interest on wearable technologies for rehabilitation and human augmentation. Systems focusing on the upper limbs are attempting to replicate the musculoskelet... Read More about A conceptual exoskeleton shoulder design for the assistance of upper limb movement.

Realizing low-impedance rendering in admittance-type haptic interfaces using the input-to-state stable approach (2017)
Journal Article
Nabeel, M., Jafari, A., & Ryu, J. H. (2017). Realizing low-impedance rendering in admittance-type haptic interfaces using the input-to-state stable approach. Proceedings of the ... IEEE/RSJ International Conference on Intelligent Robots and Systems. IEEE/RSJ International Conference on Intelligent Robots and Systems, 2017-September, 914-919. https://doi.org/10.1109/IROS.2017.8202254

© 2017 IEEE. This paper proposes an approach to enlarge the impedance range of admittance-type haptic interfaces. Admittance-type haptic interfaces have advantages over impedance-type haptic interfaces in the interaction with high impedance virtual e... Read More about Realizing low-impedance rendering in admittance-type haptic interfaces using the input-to-state stable approach.

The Input-to-State Stable (ISS) approach for stabilizing haptic interaction with virtual environments (2017)
Journal Article
Jafari, A., Nabeel, M., & Ryu, J. H. (2017). The Input-to-State Stable (ISS) approach for stabilizing haptic interaction with virtual environments. IEEE Transactions on Robotics, 33(4), 948-963. https://doi.org/10.1109/TRO.2017.2676127

© 2004-2012 IEEE. Passivity has been a major criterion for designing a stable haptic interface due to its numerous advantages. However, passivity-based controllers have suffered from the design conservatism of the passivity criterion, particularly wh... Read More about The Input-to-State Stable (ISS) approach for stabilizing haptic interaction with virtual environments.

Stable and transparent teleoperation over communication time-delay: Observer-based input-to-state stable approach (2016)
Journal Article
Jafari, A., Nabeel, M., Singh, H., & Ryu, J. (2016). Stable and transparent teleoperation over communication time-delay: Observer-based input-to-state stable approach. IEEE Haptics Symposium : [proceedings]. IEEE Haptics Symposium, 2016-April, 235-240. https://doi.org/10.1109/HAPTICS.2016.7463183

In this paper, an observer-based input-to-state stable approach is proposed to stabilize teleoperation systems over communication time-delay with better transparency compared with passivity approaches. In this paper, input-to-state stable approach is... Read More about Stable and transparent teleoperation over communication time-delay: Observer-based input-to-state stable approach.

Independent force and position control for cooperating manipulators handling an unknown object and interacting with an unknown environment (2016)
Journal Article
Ryu, J. H., Jafari, A., & Jee-Hwan, R. (2016). Independent force and position control for cooperating manipulators handling an unknown object and interacting with an unknown environment. Journal of The Franklin Institute, 353(4), 857-875. https://doi.org/10.1016/j.jfranklin.2015.12.010

© 2016 The Franklin Institute. Published by Elsevier Ltd. All rights reserved. This paper presents a unified framework for system design and control in cooperative robotic systems. It introduces a highly generalized cooperative system configuration t... Read More about Independent force and position control for cooperating manipulators handling an unknown object and interacting with an unknown environment.

Increasing the impedance range of admittance-type haptic interfaces by using Time Domain Passivity Approach (2015)
Journal Article
Hwang, J. H., Nabeel, M., Lee, J., Mehmood, U., Jafari, A., & Ryu, J. H. (2015). Increasing the impedance range of admittance-type haptic interfaces by using Time Domain Passivity Approach. Proceedings of the ... IEEE/RSJ International Conference on Intelligent Robots and Systems. IEEE/RSJ International Conference on Intelligent Robots and Systems, 2015-December, 585-590. https://doi.org/10.1109/IROS.2015.7353431

© 2015 IEEE. This paper proposes a method to increase the impedance range of admittance-type haptic interfaces. Admittance-type haptic interfaces are used in various applications that typically require interaction with high impedance virtual environm... Read More about Increasing the impedance range of admittance-type haptic interfaces by using Time Domain Passivity Approach.

Stable admittance type haptic interaction based on time domain passivity approach (2015)
Journal Article
Jafari, A., Totorkulov, K., & Ryu, J. (2015). Stable admittance type haptic interaction based on time domain passivity approach

In this paper, we propose a stable and high transparent admittance haptic display even in free space haptic rendering. Because considering admittance haptic rendering as a one-port network is not enough to detect the active energy, new representation... Read More about Stable admittance type haptic interaction based on time domain passivity approach.

Input-to-state stable approach to release the conservatism of passivity-based stable haptic interaction (2015)
Journal Article
Jafari, A., & Ryu, J. H. (2015). Input-to-state stable approach to release the conservatism of passivity-based stable haptic interaction. IEEE International Conference on Robotics and Automation, 2015-June(June), 285-290. https://doi.org/10.1109/ICRA.2015.7139013

© 2015 IEEE. Passivity has been a major criterion on designing a stable haptic interface due to many advantages. However, passivity has been suffering from its intrinsic conservatism since it only represents a small set of the whole stable region. Th... Read More about Input-to-state stable approach to release the conservatism of passivity-based stable haptic interaction.

6-DOF extension of memory-based passivation approach for stable haptic interaction (2014)
Journal Article
Jafari, A., & Ryu, J. H. (2015). 6-DOF extension of memory-based passivation approach for stable haptic interaction. Intelligent Service Robotics, 8(1), 23-34. https://doi.org/10.1007/s11370-014-0161-y

© 2014, Springer-Verlag Berlin Heidelberg. This paper extends previously proposed memory-based passivity approach (MBPA) to 6 degrees-of-freedom (DOF) haptic interactions. By introducing 6-DOF virtual proxy and virtual object, connected with haptic i... Read More about 6-DOF extension of memory-based passivation approach for stable haptic interaction.

Hybrid force-motion control of coordinated robots interacting with unknown environments (2014)
Journal Article
Jafari, A., & Ryu, J. H. (2014). Hybrid force-motion control of coordinated robots interacting with unknown environments. https://doi.org/10.1109/ICCAS.2014.6987966

© 2014 Institute of Control, Robotics and Systems (ICROS). This paper presents a unified framework for system design and control in cooperative robotic systems. It introduces a highly general cooperative system configuration involving any number of m... Read More about Hybrid force-motion control of coordinated robots interacting with unknown environments.

Transparency improved sliding-mode control design for bilateral teleoperation systems by using virtual manipulator concept (2013)
Journal Article
Jafari, A., & Ryu, J. H. (2013). Transparency improved sliding-mode control design for bilateral teleoperation systems by using virtual manipulator concept. IFAC-PapersOnLine, 3(PART 1), 21-26. https://doi.org/10.3182/20131111-3-KR-2043.00013

This paper proposes a new methodology for designing sliding mode bilateral controllers based virtual manipulator concept that aims to reach the most transparency considering parameter uncertainties and disturbances. This method shows a modified schem... Read More about Transparency improved sliding-mode control design for bilateral teleoperation systems by using virtual manipulator concept.