Wai-keung Fung

Cardiff Metropolitan University | cardiffmet · Cardiff School of Technologies

This paper presents a novel approach to speedup EMT simulation, using GPU-based computing. This paper extends earlier published works in the area, by exploiting additional parallelism inside EMT simulation. A 2D-parallel matrix-vector multiplication is used that is faster than previous 1D-methods. Also this paper implements a GPU-specific sparsity...

This paper describes how to establish performance charts for selection of network parameters for effective utilization of a bilateral teleoperated manipulator working under a wireless communication channel. The goal is to construct a set of charts that help researchers and engineers to select appropriate parameters of wireless network setup for a k...

Adaptive Resonance Theory (ART) networks are employed in robot behavior learning. Two of the difficulties in online robot behavior learning, namely, (1) exponential memory increases with time, (2) difficulty for operators to specify learning tasks accuracy and control learning attention before learning. In order to remedy the aforementioned difficu...

Using atomic force microscopy (AFM) as a nanomanipulation tool has been discussed for more than a decade. However, its lack of real-time visual feedback during manipulation has hindered its wide application. Fortunately, this problem has been overcome by our recently developed augmented reality system. By locally updating the AFM image based on rea...

This paper introduces new planning and control methods for supermedia-enhanced real-time telerobotic operations via the Internet. Supermedia is the collection of video, audio, haptic information, temperature, and other sensory feedback. However, when the communication medium used, such as the Internet, introduces random communication time delay, se...

Artificial intelligence has significantly enhanced the research paradigm and spectrum with a substantiated promise of continuous applicability in the real world domain. Artificial intelligence, the driving force of the current technological revolution, has been used in many frontiers, including education, security, gaming, finance, robotics, autono...

Pipelines are often subject to leakage due to ageing, corrosion, and weld defects, and it is difficult to avoid as the sources of leakages are diverse. Several studies have demonstrated the applicability of the machine learning model for the timely prediction of pipeline leakage. However, most of these studies rely on a large training data set for...

Artificial intelligence (AI) has a potential for impact in the diagnosis of neurological conditions, the academic consensus generally has a positive outlook regarding how AI can improve the care of stroke victims and those who suffer from neuro-degenerative conditions such as dementia. When combined with Internet of Things technology, this could fa...

This paper proposes a sliding mode control with a disturbance estimation for an underwater robot. The mobility performance of an underwater robot is influenced by modeling error, observation noise, and several disturbances such as ocean current and tidal current. Therefore, a robust control system is needed for precise motion control of an underwate...

Multiphase flows are of paramount importance in the oil and gas industry, considering that most petroleum industries produce and transport oil and gas simultaneously. However, systematic research on pipeline leakage conveying more than one phase at a time is lacking attention. In this work, a numerical method is proposed to investigate the effect o...

A low-complexity wavelet-based visual saliency model to predict the regions of human eye fixations in images using low-level features is proposed. Unlike the existing wavelet-based saliency detection models, the proposed model requires only two channels - luminance (Y) and chrominance (Cr) in YCbCr colour space for saliency computation. These two c...

This article proposes a holistic localisation framework for underwater robotic swarms to dynamically fuse multiple position estimates of an autonomous underwater vehicle while using fuzzy decision support system. A number of underwater localisation methods have been proposed in the literature for wireless sensor networks. The proposed navigation fr...

Pipelines are widely used for the transportation of hydrocarbon fluids over millions of miles all over the world. The structures of the pipelines are designed to withstand several environmental loading conditions to ensure safe and reliable distribution from point of production to the shore or distribution depot. However, leaks in pipeline networks...

Pipelines are widely used for transportation of hydrocarbon fluids over millions of miles over the world. The structures of the pipelines are designed to withstand several environmental loading conditions to ensure safe and reliable distribution from point of production to the shore or distributions deport. However, leaks in pipeline networks are o...

Localization in large-scale underwater swarm robotic systems has increasingly at-tracted research and industry communities’ attention. An optimized confidence-based localization algorithm is proposed for improving localization coverage and accuracy by promoting robots with high confidence of location estimates to refer-ences for their neighboring r...

The absence of Global Positioning System in underwater environment predominates in the challenges of underwater vehicles navigation or sensor nodes tracking. Localization of single or few underwater vehicles has been fostered in recent years. However, online simultaneous tracking of large-scale mobile sensor network is still a very challenging rese...

Localization in large-scale underwater swarm robotic systems has increasingly attracted research and industry communities' attention. An optimized confidence-based localization algorithm is proposed for improving localization coverage and accuracy by promoting robots with high confidence of location estimates to references for their neighboring rob...

A new PD-like control law is proposed in this paper to control a multistable impacting system. This control law can switch the system from a current, undesired state to a desired one by using the differences of the displacement and velocity between the current and desired states. The control law can control the multistable system without affecting...

Underwater mobile sensor node localization is a key enabling technology for several subsea missions. A novel scalable underwater localization scheme, called Best Suitable Localization Algorithm (BLSA), is proposed to dynamically fuse multiple position estimates of sensor nodes using fuzzy logic, aiming at improving localization accuracy and availab...

Underwater mobile sensor node localization is a key enabling technology for several subsea missions. A novel scalable underwater localization scheme, called Best Suitable Localization Algorithm (BLSA), is proposed to dynamically fuse multiple position estimates of sensor nodes using fuzzy logic, aiming at improving localization accuracy and availab...

This paper presents a heterogeneous computing framework to interface single board computers (SBC) to (i) distinct type of computing nodes, (ii) distinct operating systems, and (iii) distinct software applications for aeronautical surveillance system for drone delivery. The implementation platform selected is the Beagle Bone Black (BBB) having the o...

Photonic crystal fibers (PCFs) developed using nanostructured composite materials provide special optical properties. PCF light propagation and modal characteristics can be tailored by modifying their structural and material parameters. Structuring and infusion of liquid crystal materials enhances the capabilities of all silica PCFs, facilitating t...

Photonic Crystal Fibres (PCFs) developed using nanostructured composite materials provides special optical properties which can revolutionise current optical sensing technologies. The modal and propagation characteristics of the PCF can be tailored by altering their geometrical parameters and material infiltrations. A drawback of commercially avail...

This paper reports technical design of a novel experimental test facility, using haptic-enabled teleoperation of robotic manipulators, for live transmission line maintenance. The goal is to study and develop appropriate techniques in repair overhead power transmission lines by allowing linemen to wirelessly guide a remote manipulator, installed on...

Position error between motions of the master and slave end-effectors is inevitable as it originates from hard-to-avoid imperfections in controller design and model uncertainty. Moreover, when a slave manipulator is controlled through a delayed and lossy communication channel, the error between the desired motion originating from the master device a...

This paper presents a novel parallelization approach to speedup EMT simulation, using GPU-based computing. This paper extends earlier published works in the area, by exploiting additional parallelism to accelerate EMT simulation. A 2D-parallel matrix-vector multiplication is used that is faster than previous 1D-methods. Also this paper implements a...

Condition monitoring of offshore structures is an indispensable task in the oil and gas industry. Fibre Bragg Grating (FBG) is the key technology used down-hole in order to sense different physical parameters such as strain, vibration, etc. This paper investigates the effect of FBG sensor positions on its reflected signal, in order to optimise the...

Photonic crystal fibre (PCF)–fibre bragg grating (FBG) integration opens up new possibilities in multi-parameter fibre-optic sensing, owing to their active control over light characteristics and mode confinements. Their integration results in a mismatch in their mode field diameters (MFDs), which in turn causes various types of losses such as confi...

This paper presents the procedure of establishing performance charts for effective utilization of a teleoperated hydraulic manipulator working under wireless communication channels. A teleoperated system, comprising a master haptic device and an industrial hydraulic manipulator, is constructed. The master and slave communicate through a communicati...

In this paper, the effects of time delay and packet loss incurred in communication channel, are examined on the performance of bilaterally controlled hydraulic actuators under various control schemes. The controllers are force reflection (FR), position error (PE), combined force reflection and position error (FP), and four channels (FC). The performan...

This paper presents a proof of concept experiment designed to quantitatively and qualitatively test the supermedia streaming capabilities for telepresence via cellular data networks using a remote controlled (RC) helicopter. In the experiment, the RC helicopter flies with two smartphones attached. The first smartphone streams Skype video, 6-axis te...

In this paper we discuss various approaches to simulating real-time Internet-based teleoperation systems. Focus is on simulation of the communication link, which is a critical component in teleoperation systems. Some of the objectives of simulations are to compare the performance of operators in fixed network conditions and to compare the performan...

In this paper electromagnetic transient (EMT) simulation of large scale power systems using graphics processing unit (GPU) based computing is demonstrated. As the size of power sys-tem networks increases, the simulation time using conven-tional central processing units (CPUs) based simulation in-creases drastically. This paper proposes a hybrid CPU...

In this paper electromagnetic transient (EMT) simulation of large scale power systems using graphics processing unit (GPU) based computing is demonstrated. As the size of power system networks increases, the simulation time using conventional central processing units (CPUs) based simulation increases drastically. This paper proposes a hybrid CPU-GP...

In this paper we discuss various approaches to simulating real-time Internet-based teleoperation systems. Fo- cus is on simulation of the communication link, which is a crit- ical component in teleoperation systems. Some of the objectives of simulations are to compare the performance of operators in fixed network conditions and to compare the perfo...

In this paper suitability of applying graphics processing unit (GPU) based computing for electromagnetic transient (EMT) simulation of large scale power systems is demonstrated. As the network size increases there is a corresponding increase in simulation time with conventional central processing unit (CPU) based simulation tools. The paper shows t...

In this paper suitability of applying graphics pro-cessing unit (GPU) based computing for electromagnetic transient (EMT) simulation of large scale power systems is demonstrated. As the network size increases there is a corresponding increase in simulation time with conventional central processing unit (CPU) based simulation tools. The paper shows...

In this paper, the effect of deformable environment to the performance of three bilateral teleoperation control schemes for hydraulic actuators are investigated through dynamic simulation. The considered schemes are Force Reflection, Position Error and Lyapunov feedback controllers. Two type of environments are considered, first is spring model and...

Auto-focusing is one of the key issues in motorized biological microscopes as it strongly affects the quality of the microscopic images. Auto-focusing is a difficult problem because the size of biological objects is as small as a few micrometers, and the problem is even more challenging when the density of the image content is low. In this paper, w...

Providing force feedback along with other sensory information can greatly increase task quality, productivity, and safety during teleoperation of hydraulic manipulators. However, as compared to the class of electrically-actuated robots, research on application of bilateral control schemes applied to the class of hydraulic manipulators is sparse. In...

In this paper, we present experimental results of implementing five bilateral control schemes, widely used for electro-mechanical systems, to a hydraulic actuator. The goal is to investigate the applicability of each control scheme to a hydraulic actuator and compare their performances on a common system. The considered schemes are 'force reflectio...

An image compression method combining discrete wavelet transform (DWT) and vector quantization (VQ) is presented. First, a three-level DWT is performed on the original image resulting in ten separate subbands (ten codebooks are generated using the Self Organizing Feature Map algorithm, which are then used in Vector Quantization, of the wavelet tran...

This paper reports a case study of using single 3D stereoscopic visual feedback for real-time teleoperation of dexterous tasks. In traditional teleoperation systems, real-time visual feedbacks of multiple monoscopic views of the robot workspace are provided for remote operator. However, it is difficult for the operator to control remote robot to pe...

For Internet based real-time teleoperation systems, random time delay can cause instability in the closed loop control system and hence hinder task accomplishment. Event based control systems have been proposed to overcome the instability caused by the random time delay. High latency at the transport layer can still impede effective and reliable ex...

An improved method is provided for performing nanomanipulations using an atomic force microscope. The method includes: performing a nanomanipulation operation on a sample surface using an atomic force microscope; determining force data for forces that are being applied to the tip of the cantilever during the nanomanipulation operation, where the fo...

The use of atomic force microscope (AFM) as a nanomanipulator has been evolving for various kinds of nano-manipulation tasks. Due to the bow effect of the piezo scanner of the AFM, the AFM space is different from the Cartesian space. Traditional nanomanipulation based on AFM is only a 2-D operation and does not consider the bow effect of the piezot...

The paper addresses features extraction of sensor data for robot behavior learning using factor analysis. Redundancies in sensor types and quantities are common in sensing competence of robots. The redundancies cause the high dimensionality of the perceptual space. It is impractical to incorporate all available sensor information in decision-making...

In real-time Internet based teleoperation, different robotic tasks have different dexterity requirements during task progress and thus different network resources are required for safe and reliable task accomplishment. In order to control remote manipulators efficiently and smoothly via the Internet, dynamic bandwidth allocation is crucial to succe...

Previous studies on nanomanipulation using Atomic Force Microscope (AFM) go through the scan-design-manipulation-scan cycle, in which an operator does not have any real-time visual feedback during manipulation. In this paper, a simple model of tip-substrate-object interactive forces has been presented for the qualitative and quantitative analysis....

This paper presents a mobile robot fro routine delivery tasks of medicine, specimen, and medical devices from one station to another in hospitals. This hospital transport robot uses the fluorescent lamps on the ceiling of the corridor as natural landmarks to localize its position and orientation. A simple and efficient algorithm has been developed...

The use of atomic force microscope (AFM) as a nanomanipulator has been evolving for various kinds of nanomanipulation tasks. Due to the bow effect of the piezo scanner of the AFM, the AFM space is different from the Cartesian space. In this paper, different 3-D nanomanipulation tasks using AFM such as nanolithography, pushing and cutting are discus...

By introducing haptic force feedback, nanomanipulation using the AFM becomes easier. However, this technique has been impeded by tip displacement due to the softness of AFM cantilever. In this paper, a novel nanomanipulation system assisted by augmented reality is presented. By analyzing the cantilever-tip interaction with the environment, the norm...

By using the technique of perspective frame control, the stability of real-time Internet based teleoperation systems can be guaranteed. The system efficiency, however, is still highly sensitive to the network quality. In this paper, we investigate on how to improve the real-time system efficiency of teleoperation systems in both control and resourc...

Robotic operations carried out via the Internet face several challenges and difficulties. These range from human–computer interfacing and human–robot interaction to overcoming random time delay and task synchronization. These limitations are intensified when multi-operators at multi-sites are collaboratively teleoperating multi-robots to achieve a...

This paper presents an QoS (quality of service) based control system of teleoperation via the Internet. Quality of service on the Internet refers to a set of quality requirements on the performance of the data transmission necessary to achieve the required functionality of an application. The quality of data transmission via the Internet is measure...

The e-world has added a new dimension to many of the traditional concepts in industrial applications and everyday life. Many words encountered nowadays are prefixed by the letter "e" to reflect their close relation to the electronic world. Therefore, it was not surprising when researchers and businesses started developing "e-services", which are si...

This paper presents a QoS based efficiency improving scheme for Internet-based teleoperation. One of the widely used QoS parameters for showing network status is network delay. With the help of event-based control technique, the stability of the teleoperation systems is guaranteed under random network delay. This paper investigates how to improve t...

This paper presents an QoS (quality of service) based control system of teleoperation via the Internet. Quality of service on the Internet refers to a set of quality requirements on the performance of the data transmission necessary to achieve the required functionality of an application. The quality of data transmission via the Internet is measure...

In the past decade robotics and the Internet, fed by the great advances in computing and networking, matured into giant interdisci-plinary scientific fields. Therefore, it is not surprising that many are try-ing to merge these two technologies and develop Internet-based robotic teleoperation. More interestingly, Internet-based bilateral teleoperati...

Many tasks can be done easily by humans turn out to be very difficult to accomplish with a teleoperated robot. The main reason for this is the lack of tactile sensing, which cannot be replaced by visual feedback alone. Once haptic devices are developed, their potential in many fields is obvious. Especially, in teleoperation systems, where haptic fe...

A game-theoretic formulation of adaptive categorization mechanism for ART-type networks is proposed in this paper. We have derived the game-theoretic model Γ AC for competitive processes of categorization of ART-type networks and an update rule for vigilance parameters using the concept of learning automata. Numbers of clusters generated by ART ada...

Robotic operations carried out via the Internet face several challenges and difficulties. These range from human-computer interfacing and human-robot interaction to overcoming random time delay and task synchronization. These limitations are intensified when multi-operators at multisites are collaboratively teleoperating multirobots to achieve a ce...

Robotic operations carried out via the Internet face several challenges and difficulties. These range from human-computer interfacing and human-robot interaction to overcoming random time delay and task synchronization. These limitations are intensified when multi-operators at multi-sites are collaboratively tele-operating multi-robots to achieve a...

The growth of the Internet has been accompanied by an increase in its applications. One of the most interesting of these is teleoperation, where the Internet is used as a bridge between operators and machines. However, teleoperation over the Internet comes with several problems: delay, lost packets and disconnection. All of these limitations may ca...

A new formulation of an adaptive categorization game of ART-type neural networks is described in this paper. Learning automata dynamics is introduced into the adaptive categorization game in ART-type networks so that the vigilance parameter ρ is adjusted to give variable-sized clusters. Moreover, repeated game analysis is also conducted on the lear...

The development of autonomous robot navigation systems has been a challenge for robot specialists for decades. Different guiding or navigation styles are required for autonomous robots to operate in the intelligent space efficiently and safely under different situations. In this paper an extension of the classical potential based guiding model is p...