Chi-Tsun Cheng

RMIT University | RMIT · Manufacturing, Materials and Mechatronics

The extensive adoption of exotic materials in industries such as defence and aerospace has pushed the corresponding manufacturing system to be flexible, cut-anything and precise. A systematic literature review has shown that combining industrial robot (IR) and Electric Discharge Machining (EDM) stands out as a non-contact and near-zero force manufa...

This study aims to explore various domains within Industry 4.0 (I4.0) and energy productivity in Australian context. In doing this, the study analyses I4.0 technologies & services, barriers to I4.0 for energy productivity, regulatory framework, multiple benefits of I4.0 technologies, relevant business models, and roadmap to I4.0. The findings show...

Industry 4.0 (I4.0) grants businesses in the manufacturing sector significant benefits in terms of productivity and efficiency; however, industries must strive to reach a level of technological readiness and acquire the necessary expertise to implement and integrate I4.0 technologies to enhance their processes. This paper presents a framework desig...

Human movements in the workspace usually have non-negligible relations with air quality parameters (e.g., CO$_2$, PM2.5, and PM10). We establish a system to monitor indoor human mobility with air quality and assess the interrelationship between these two types of time series data. More specifically, a sensor network was designed in indoor environme...

The unmanned aerial vehicle (UAV) enabled communication technology is regarded as an efficient and effective solution to provide emergency data uploading for some special cases where existing cellular infrastructures cannot provide reliable services to large-scale ground users (GUs). In the face of large-scale dynamic networks where the number and...

This Special Issue of IEEE Journal on Emerging and Selected Topics in Circuits and Systems (JETCAS) is dedicated to showcasing the latest developments and achievements in circuits and systems for Industry X.0 applications.

The advent of the Internet of Things (IoT) has triggered an increased demand for sensing devices with multiple integrated wireless transceivers. These platforms often support the advantageous use of multiple radio technologies to exploit their differing characteristics. Intelligent radio selection techniques allow these systems to become highly ada...

While traditional industrial robots participate in repetitive manufacturing processes from behind caged safety enclosures, collaborative robots (cobots) offer a highly flexible and human-interactive solution to manufacturing automation. Rather than operating from within cages, safety features such as force and proximity sensors and programmed prote...

In this paper, to address the problem of detecting the presence of human in indoor environments in the presence of moving clutter sources, an indoor human detection method that utilizes random forest to process micro-Doppler signatures and a single pair of TX/RX unit is proposed. In contrast to most of the existing methods that use both distance in...

Conventional heating ventilation and air-conditioning (HVAC) controllers have been designed to mainly control the temperature of a confined compartment, such as a room or a cabin of a vehicle. Other important parameters related to the thermal comfort and indoor air quality (IAQ) of the confined compartment have often been ignored. In this project,...

Assistance systems have been widely adopted in the manufacturing sector to facilitate various processes and tasks in production environments. However, existing systems are mostly equipped with rigid functional logic and do not provide individual user experiences or adapt to their capabilities. This work integrates human factors in assistance system...

A trajectory can be reconstructed by integrating acceleration and angular velocity (i.e. $\omega$ ) sampled by a single inertial measurement unit (IMU) which consists of an accelerometer (ACC) and gyroscope (GYRO). To reduce the system power consumption, a GYRO-free-IMU (GF-IMU) method was proposed which disabled the more power-consuming GYRO and...

With the increasing number of Internet of Things (IoT), Industry 4.0 (I4.0), and mobile devices, it can be expected that base stations will have to serve more and more clients with a limited number of antennas. For their broadcast channels, nonorthogonal multiple access (NOMA) and blind interference alignment (BIA) are two efficient and commonly ad...

IAQ monitoring studies have gained renewed interest post COVID-19. Furthermore, accessibility to the corresponding enabling technologies has improved considerably in terms of cost and requisite knowledge. This paper aims to outline the key decisions involved for researchers and building managers alike to seek to implement their own environmental mo...

Virtual Reality (VR) offers novel possibilities for remote training regardless of the availability of the actual equipment, the presence of specialists, and the training locations. Research shows that training environments that adapt to users' preferences and performance can promote more effective learning. However, the observed results can hardly...

This paper investigates the importance of standardising and maintaining the transparency of advanced driver-assistance systems (ADAS) functions nomenclature, designs, and operations in all categories up until fully autonomous vehicles. The aim of this paper is to reveal the discrepancies in ADAS functions across automakers and discuss the underlyin...

Gamification applications are on the rise in the manufacturing sector to customize working scenarios, offer user-specific feedback, and provide personalized learning offerings. Commonly, different sensors are integrated into work environments to track workers’ actions. Game elements are selected according to the work task and users’ preferences. Ho...

The tremendous advancement of Internet-of-things (IoT) has proliferated the interaction between the physical and cyber worlds. Consumer electronics, as the first tier in the physical world, would play a crucial role to enable ubiquitous information exchange. The adoption of IoT technologies will inevitably enhance the maturity of consumer products...

Animations of virtual items in AR support systems are typically predefined and lack interactions with dynamic physical environments. AR applications rarely consider users’ preferences and do not provide customized spontaneous support under unknown situations. This research focuses on developing adaptive, error-tolerant AR systems based on directed...

In theera of Internet of Things (IoT), sensor plays a more vital role and its quality has a great impact on final measurement. From the viewpoint of final measurement, there are two kinds of effects: bias-only measurement and error-growth measurement. The bias-only measurement can be directly read from a sensing device, and each measurement is only...

Data collection is an essential part of Beyond-5G and Internet of Things applications. In urban area, heterogeneous access points such as Wi-Fi routers and base stations can meet the required communication coverage and bandwidth in data collection processes. However, in remote area, without communication infrastructures, it is hard to guarantee the...

In the last decade, Australian SMEs are steadily becoming more digitally engaged, but they still face issues and barriers to fully adopt Industry 4.0 (I4.0). Among the tools that I4.0 encompasses, digital twin (DT) and digital thread (DTH) technologies hold significant interest and value. Some of the challenges are the lack of expertise in developi...

The fourth industrial revolution introduces disruptive technologies to production environments. One of these technologies are multi-agent systems (MASs), where agents virtualize machines. However, the agent's actual performances in production environments can hardly be estimated as most research has been focusing on isolated projects and specific s...

In this chapter, the authors focus on the impact of artificial intelligence (AI) and associated technological changes on work and jobs in Australia’s utility sector. The chapter comprises extensive commentary on the collective effects of AI incorporating machine learning, big data, blockchain, and other technological advances. The aim is to attempt...

This paper explores the problem of energy-efficient shortest path planning on off-road, natural, real-life terrain for unmanned ground vehicles (UGVs). We present a greedy path planning algorithm based on a composite metric routing approach that combines the energy consumption and distance of the path. In our work, we consider the Terramechanics be...

Unmanned aerial vehicles (UAVs) are usually dispatched as mobile sinks to assist data collection in large-scale wireless sensor networks (WSNs). However, when considering the limitations of UAV’s mobility and communication capabilities in a large-scale WSN, some sensor nodes may run out of storage space as they fail to offload their data to the UAV...

Unmanned aerial vehicles (UAVs) are usually dispatched as mobile sinks to assist data collection in large-scale wireless sensor networks (WSNs). However, when considering the limitations of UAV's mobility and communication capabilities in a large-scale WSN, some sensor nodes may run out of storage space as they fail to offload their data to the UAV...

In smart grid, voltage control feeds back state information from sensors to controllers via wired or wireless channels to stabilize the electricity distribution. When wireless channel is applied, because of the interference among wireless sensors, scheduling is necessary for efficient and reliable data aggregations. Previous work proved that delay-...

This paper provides an overview of the current state-of-the-art digital twin and digital thread technology in industrial operations. Both are transformational technologies that have the advantage of improving the efficiency of current design and manufacturing. Digital twin is an important element of the Industry 4.0 digitalization process; however,...

Industry 4.0 imposes many challenges for manufacturing companies and their employees. Innovative and effective training strategies are required to cope with fast-changing production environments and new manufacturing technologies. Virtual Reality (VR) offers new ways of on-the-job, on-demand, and off-premise training. A novel concept and evaluation...

In general, a two-dimensional (2D) moving trajectory can be reconstructed using data collected from a 6-axis IMU (inertial measurement unit), which consists of a 3-axis gyroscope and a 3-axis accelerometer. Since the power consumption of a gyroscope is significantly larger than that of an accelerometer, to be energy-efficient, it is more preferable...

While bringing new opportunities, the Industry 4.0 movement also imposes new challenges to the manufacturing industry and all its stakeholders. In this competitive environment, a skilled and engaged workforce is a key to success. Gamification can generate valuable feedbacks for improving employees’ engagement and performance. Currently, Gamificatio...

Mobile sensor networks (MSNs) are good candidates for large-scale unattended surveillance applications. However, it is challenging to track moving targets due to their complex dynamic behaviors. Semiflocking algorithms have been proven to be efficient in controlling MSNs in both area coverage and target tracking applications. While many existing li...

Progressive digitalization and globalization require companies to be more flexible and adaptable. To achieve this, qualified and committed employees are indispensable. Gamification offers the possibility to support employees individually in their activities and to motivate them by means of feedback mechanisms. This research presents a gamification...

This paper considers the number of mode-switching associated with reconfigurable-antenna-based blind interference alignment (BIA) scheme for a 2-user MISO interference channel (IC). It is assumed that each user is equipped with a single reconfigurable antenna, which can switch among multiple independent modes. The switching-oriented BIA (S-BIA) sch...

Die Vielfältigkeit von Produkten und deren Herstellungsverfahren machen manuelle Tätigkeiten auch im Zuge von Industrie 4.0 unersetzlich. Flexible Handarbeitsplätze ermöglichen hierbei eine ergonomische und effiziente Produktion über alle Branchen hinweg. Um die Mitarbeiter(in-nen) optimal zu unterstützen werden diverse Technologien, wie beispielsw...

During 2019, RMIT researchers interviewed executives from SMEs and larger companies across Australia about their views on digital operations and I4.0. This paper draws on those interviews, and experience gained from RMIT’s ongoing engagement with its partners in the advanced manufacturing sector, to examine the specific benefits, challenges and opp...

Preface Our future is the world we are going to live in, attracting our fantasies, speculations, fears and hopes. We really would like to know something about it and want to be prepared. Therefore, we observe trends. An obvious trend is that our world gets more and more connected. Information is seamlessly following and doing this quickly. We learn...

Additive manufacturing technologies have been widely applied in both household and industrial applications. The fabrication time of a 3D printed object can be shortened by optimizing its segments printing order. The computational times required by existing nozzle path planning algorithms can increase rapidly with the number of printing segments. In...

Augmented Reality (AR) and Virtual Reality (VR) play an important role for the implementation of Industry 4.0-especially in the area of virtual prototyping, manufacturing and maintenance. Thus, a holistic integration of these technologies in existing processes structures is essential to ensure future competitiveness of companies. Current research m...

The German government presented the concepts of Industrie 4.0 at the Hannover fair in 2012. Based on this, the German "Hightech-Strategie 2020" was initiated to establish Germany as the leading supplier for cyber-physical systems. This strategy includes implementation recommendations for future technologies as well as promotions for avant-garde inn...

Die Nutzung von Virtual Reality (VR) und Augmented Reality (AR) in der Industrie nimmt durch die Weiterentwicklung von Hard- und Software stetig zu. Die Einordnung wissenschaftlicher Veröffentlichungen in einen für virtuelle Technologien geeigneten, generischen Lebenszyklus zeigt, dass VR Applikationen vorrangig für Planungs- und Trainingsanwendung...

Mobile sensor networks (MSNs) are utilized in many sensing applications that require both target seeking and tracking capabilities. Dynamics of mobile agents and the interactions among them introduce new challenges in designing robust cooperative control mechanisms. In this paper, a distributed semiflocking algorithm inspired by Temnothorax albipen...

In infrastructure-as-a-service environments, Cloud data centers employ virtualization technology to host various applications in virtual machines (VMs) and enable application isolation on shared physical resources. Additionally, live VM migration has been adopted to perform load balancing by moving VMs across distinct hosts. However, co-located VMs...

Efficient energy and temperature management techniques are essential elements for operators of cloud data centers. Dynamic virtual machine (VM) consolidation using live migration techniques presents a great opportunity for cloud service providers to adaptively reduce energy consumption and optimize their resource utilization. In recent studies, pow...

Vorwort Zum 20. Mal trifft sich die Community zum Leitkongress der Mess- und Automatisierungstechnik AUTOMATION im Juli 2019. Unter dem Motto „Autonomous Systems and 5G in Connected Industries“ erwartet Sie ein anspruchsvolles Programm! Wie wirken sich künstliche Intelligenz und autonome Systeme auf die Fertigungs- und Prozessautomation der Zukunft...

Layered additive manufacturing, also known as 3D printing, has revolutionized transitional manufacturing processes. Fabrication of 3D models with complex structures is now feasible with 3D printing technologies. By performing careful tool-path optimization, the printing process can be speeded up, while the visual quality of printed objects can be i...

Mobile sensor networks (MSNs) can provide sensing coverage to large areas of interest (AoIs). Area coverage and target tracking capabilities of MSNs are heavily depending on their motion control and coordination mechanisms. Many existing MSN motion control algorithms ignore or poorly utilize available information from their operating environment, t...

Mobile sensor networks (MSNs) with semi-flocking control protocols have demonstrated promising performances in both area coverage and target tracking. However, they may not operate at their highest efficiencies due to poor utilization of local information and deficient motion coordinations among mobile nodes. In this paper, a distributed semi-flock...

Finding a shortest feasible path between two given locations is a common problem in many real-world applications. Previous studies have shown that mobile platforms would consume excessive energy when moving along shortest paths on uneven terrains, which often consist of rapid elevation changes. Mobile platforms powered by portable energy sources ma...

Anti-flocking controlled mobile sensor networks (MSNs) have demonstrated impressive dynamic area coverage performances. Even though MSNs are often utilized in outdoor environments that consist of uneven terrains, existing anti-flocking control protocols are designed for flat terrain navigation. Thus they tend to maneuver mobile sensory units along...

After a blackout, it is essential to restore the blackout area rapidly to minimize possible losses. In parallel restoration, the blackout area is first partitioned into several subsystems which will then be restored in parallel to accelerate the restoration process. In order to ensure restoration reliability, each subsystem should have enough gener...

Efficient path planning has an utmost importance in the domain of autonomous navigation. Even though shortest path planning has been well discussed in the past, the same techniques might not always be used to find the fastest path in outdoor environments due to the inability of mobile agents to travel at their peak speed everywhere in irregular ter...

Live migration, which allows virtual machines (VMs) to move across distinct physical hosts, is widely adopted for realizing energy saving and load balancing in modern Cloud data centers. However, putting VMs with high correlations on their CPU utilization patterns onto the same host is very likely to trigger overloading incidents and commit Service...

It is essential to rapidly restore a power system after a blackout to minimize the economic losses and negative social impact. The most common approach of accelerating the restoration process is by restoring the complete network as several subsystems in parallel. Even though a parallel restoration process has obvious advantages over its sequential...

Internet of Things (IoT) systems comprise massive volumes of smart devices. Through exchanges of information, smart objects are capable of reasoning and generate higher level of intelligence. The effectiveness of data collection processes is a key factor to the success of IoT systems as it can seriously affect the freshness of the captured data. Ef...

It has been studied that a few informed individuals in a group of interacting dynamic agents can influence the majority to follow the position and velocity of a virtual leader. Previously it has been shown that a cluster-based selection of informed agents can drive more agents to follow the virtual leader compared to a random selection. However, a...

Additive-layered manufacturing has gained attention in recent years as it has many advantages over conventional injection moulding methods. The optimization of printing trajectories can be formulated as a travelling salesman problem (TSP) and solved accordingly. However, computational complexities of ordinary TSP solvers can increase tremendously w...

In this paper, Rapidly Replanning A* (RRA*) algorithm is proposed for path planning and replanning in partially unknown environments. RRA* uses an effective mechanism to reuse previous search results, which considerably accelerates its replanning process compared to repetitive replanning from scratch. RRA* guarantees to find an optimal path from th...

Rapid prototyping and product customization have become more convenient with the emergence of 3D printing technologies. In extrusion deposition based 3D printing, objects are built by connecting many lines of filament, layer by layer. The efficiency of the printing process can be improved by optimizing motion paths of the printing nozzle. In this p...

Existing path planning algorithms are capable of finding physically feasible, shortest, and energy-efficient paths for mobile robots navigating on uneven terrains. However, shortest paths on uneven terrains are often energy inefficient while energy-optimal paths usually take long time to be traversed. Therefore, due to time and energy constraints i...

Three dimensional (3D) printing can be used to manufacture many different objects range from toys to hi-tech robot parts. This paper investigates 3D printer trajectory planning to improve the speed of the printing process. The printing speed mainly depends on the motion speed and path of the printing nozzle. We use triangular and trapezoidal veloci...

Mobile sensor networks (MSNs) are often used for monitoring large areas of interest (AoI) in remote and hostile environments which can be highly dynamic in nature. Due to the infrastructure cost, MSNs usually consist of limited number of sensor nodes. In order to cover large AoI, the mobile nodes have to move in an environment while monitoring the...

It is always challenging for deaf and speech-impaired people to communicate with non-sign language users. A real-time sign language recognition system using 3D motion sensors could lower the aforementioned communication barrier. However, most existing gesture recognition systems are adopting a single sensor framework, whose performance is susceptib...

Recently proposed Dynamic Z* heuristic search algorithm enables mobile robots navigating on uneven terrains to replan energy-efficient paths using previous search results whenever an obstacle is encountered. This paper proposes some vital improvements to Dynamic Z* by optimizing the use of previous search results in replanning. Simulation results s...

Mobile robots are often utilized in remote and hostile outdoor environments with uncertainties and unknown dangerous. The energy-efficient paths generated based on prior information can be impracticable due to the changes in the environment. Recently proposed Z* search algorithm is capable of finding physically feasible energy-efficient paths on un...

Motions of mobile robots need to be optimized to minimize their energy consumption to ensure long periods of continuous operations. Shortest paths do not always guarantee the minimum energy consumption of mobile robots. Moreover, they are not always feasible due to climbing constraints of mobile robots, especially on steep terrains. We utilize a he...

Mobile sensor networks (MSNs) are commonly used for monitoring an area of interest (AoI) in security and surveillance systems. Maximizing the area coverage is one of the primary objectives of such systems. With the added mobility over traditional stationary sensor nodes, mobile nodes can adjust their positions inside the AoI to increase the overall...

Automatic sign language recognition plays an important role in communications for sign language users. Most existing sign language recognition systems use single sensor input. However, such systems may fail to recognize hand gestures correctly due to occluded regions of hand gestures. In this work, we propose a novel system for real-time recognitio...

Recent literature on flocking in multi-agent systems show that a minority of informed agents in a group of dynamic agents can influence a majority to follow a virtual leader. However, it is not reported how to select these informed agents from the group in order to increase the number of agents which will eventually follow the virtual leader. In th...

A wireless sensor network (WSN) consists of a large number of wireless sensor nodes that collect information from their sensing terrain. Wireless sensor nodes are, in general, battery-powered devices with limited processing and transmission power. Therefore, the lifetime of WSNs heavily depends on their energy efficiency. Multiple-cluster 2-hop (MC...

Mobile robots are increasingly getting popular in outdoor applications. Long period of continuous operations are common in such applications. Therefore, robot motions need to be optimized to minimize their energy consumption. Shortest paths do not always guarantee minimum energy consumptions of mobile robots. This paper proposes a novel algorithm t...

Data clustering is a frequently used technique in finance, computer science, and engineering. In most of the applications, cluster sizes are either constrained to particular values or available as prior knowledge. Unfortunately, traditional clustering methods cannot impose constrains on cluster sizes. In this paper, we propose some vital modificati...