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Dr Aghil Jafari's Outputs (43)

Enhancing the force transparency of time domain passivity approach: Observer-based gradient controller (2019)
Presentation / Conference Contribution

Passivity has been the most often used constraint for the stable controller design of bilateral teleoperation systems. Especially, Time Domain Passivity Approach (TDPA) has been used in many applications since it has been known as one of the least co... Read More about Enhancing the force transparency of time domain passivity approach: Observer-based gradient controller.

Multi degree-of-freedom successive stiffness increment approach for high stiffness haptic interaction (2016)
Presentation / Conference Contribution

In haptic interaction, stability and the object’s hardness perception are of great significance. Although numerous studies have been done for stable haptic interaction, however, most of them sacrifice the actual displayed stiffness as a cost of stabi... Read More about Multi degree-of-freedom successive stiffness increment approach for high stiffness haptic interaction.

Independent force and position control for cooperating manipulators handling an unknown object and interacting with an unknown environment (2016)
Journal Article

© 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.

Sliding mode hybrid impedance control of robot manipulators interacting with unknown environments using VSMRC method (2013)
Presentation / Conference Contribution

In the present paper, the objective of hybrid impedance control is specified and a robust hybrid impedance control approach is proposed. Based on the concept of hybrid control, the task space is decomposed into position and force controlled subspaces... Read More about Sliding mode hybrid impedance control of robot manipulators interacting with unknown environments using VSMRC method.

Application of machine learning towards design optimisation of bio-inspired transfemoral prosthetic socket for robotic leg test rig
Presentation / Conference Contribution

In the past century many medical advancements in prosthetics have been achieved, however, discomfort in prosthetic socket remains one of the toughest challenges faced by both amputees and prosthetists. Wearing an uncomfortable socket can lead to user... Read More about Application of machine learning towards design optimisation of bio-inspired transfemoral prosthetic socket for robotic leg test rig.

Input-to-state stable approach to release the conservatism of passivity-based stable haptic interaction
Presentation / Conference Contribution

© 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.

Increasing the impedance range of admittance-type haptic interfaces by using Time Domain Passivity Approach
Presentation / Conference Contribution

© 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 and transparent teleoperation over communication time-delay: Observer-based input-to-state stable approach
Presentation / Conference Contribution

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.

Application of machine learning towards design optimisation of bio-inspired transfemoral prosthetic socket for robotic leg test rig
Presentation / Conference Contribution

In the past century many medical advancements in prosthetics have been achieved, however, discomfort in prosthetic socket remains one of the toughest challenges faced by both amputees and prosthetists. Wearing an uncomfortable socket can lead to user... Read More about Application of machine learning towards design optimisation of bio-inspired transfemoral prosthetic socket for robotic leg test rig.

The robotic socket: A robotic design and biomimetic application of an auto-adjusting prosthetic socket prototype for above-knee amputees
Presentation / Conference Contribution

Comfort in prosthetic sockets remains a significant challenge for many amputees, particularly for above-knee amputees bearing substantial weight on their soft tissue [1], [2]. The predominant source of discomfort often originates from swelling of the... Read More about The robotic socket: A robotic design and biomimetic application of an auto-adjusting prosthetic socket prototype for above-knee amputees.

Integration of computer vision in a testing facility for prosthetic joint inspection and performance assessment
Presentation / Conference Contribution

This paper presents a computer vision system within a test facility for prosthetic joint inspection and performance by analysing range of motion data. Testing with individuals rather than using a testing facility can cause issues, such as irritation,... Read More about Integration of computer vision in a testing facility for prosthetic joint inspection and performance assessment.

Mimicking condylar knee to design bio-inspired robotic knee joint based on magnetic resonance imaging
Presentation / Conference Contribution

The process of designing bio-inspired knee joint has been a challenging issue due to the complicated kinematics and dynamics of the human knee joint. This paper addresses this issue by presenting a design methodology that has been used to model the h... Read More about Mimicking condylar knee to design bio-inspired robotic knee joint based on magnetic resonance imaging.

Investigation into the customization of a transfemoral prosthetic socket to minimize discomfort for residual limb (RL) volume change
Presentation / Conference Contribution

It has been estimated that approximately 7000 people undergo limb amputation in the UK every year [1]. This issue is even more significant in the US, where over 150,000 people undergo lower limb extremity amputations, and this number is predicted to... Read More about Investigation into the customization of a transfemoral prosthetic socket to minimize discomfort for residual limb (RL) volume change.

Sustainable transportation solutions: Life cycle analysis of emissions reduction in heavy duty vehicles under evolving EU standards
Presentation / Conference Contribution

This paper presents a detailed analysis of operational emissions and energy use for Diesel and Compressed Natural Gas (CNG) Heavy Duty Vehicles (HDVs) under the evolving EU7 regulatory standards, which are expected to be implemented by 2027. By focus... Read More about Sustainable transportation solutions: Life cycle analysis of emissions reduction in heavy duty vehicles under evolving EU standards.

Network formulation and stability improvement of a bilateral teleoperation system with admittance-type master interfaces
Presentation / Conference Contribution

© 2015 IEEE. This paper introduces a network formulation of bilateral teleoperation systems with admittance-type master interfaces to improve their stability range with Time Domain Passivity Approach (TDPA). Since traditional network representation o... Read More about Network formulation and stability improvement of a bilateral teleoperation system with admittance-type master interfaces.

Transparency improved sliding-mode control design for bilateral teleoperation systems by using virtual manipulator concept
Presentation / Conference Contribution

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.

Design of anatomy-based 3D patient-specific knee replacement implant model from medical imaging
Presentation / Conference Contribution

This paper focuses on the design of an anatomy-based 3D patient-specific knee replacement implant model, which is derived from medical imaging. The investigation extracted the knee profiles from MRI scans to develop a 3D model of the knee, including... Read More about Design of anatomy-based 3D patient-specific knee replacement implant model from medical imaging.

Realizing low-impedance rendering in admittance-type haptic interfaces using the input-to-state stable approach
Presentation / Conference Contribution

© 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.

Modelling of a Bio-Inspired Knee Joint and Design of an Energy Saving Exoskeleton Based on Performance Maps Optimisation for Condylar Knee Prosthetics
Presentation / Conference Contribution

© 2018 IEEE. The process of designing bio-inspired knee joint for prosthetics/exoskeletons has been a challenging issue due to the complicated relationships between the performance criteria and the link lengths of the design space, or workspace in th... Read More about Modelling of a Bio-Inspired Knee Joint and Design of an Energy Saving Exoskeleton Based on Performance Maps Optimisation for Condylar Knee Prosthetics.

An adaptive hybrid force/motion control design for robot manipulators interacting in constrained motion with unknown non-rigid environments
Presentation / Conference Contribution

In the present paper, the objective of hybrid control is specified and an adaptive hybrid force/motion control approach is proposed. Based on the concept of hybrid control, the task space is decomposed into position and force controlled subspaces. An... Read More about An adaptive hybrid force/motion control design for robot manipulators interacting in constrained motion with unknown non-rigid environments.

Independent force and position control for cooperating manipulators handling an unknown object interacting with an unknown environment
Presentation / Conference Contribution

In this paper, we consider two manipulators grasping a rigid object in contact with a deformable working surface, whose real physical parameters are unknown. Dynamics of the closed chain mechanism is expressed based on the objects center of mass, and... Read More about Independent force and position control for cooperating manipulators handling an unknown object interacting with an unknown environment.