With the recent development of new technologies such as the Internet of Things (IoT), Cyber-Physical Systems (CPS), and cloud-based systems, the smart manufacturing concept based on ICT or AI is expected to have tremendous potential to realize a digital transformation with customer involvement in production. The role of production will need to change accordingly, as it is obvious that the traditional business model based on process chains for production functionality has limitations for further growth. In production, it is necessary to consider value chains with service factors for adding innovative value to products. Value creation is an important concept to the realization of a sustainable ecosystem in production.

This special issue addresses the latest research on value creation in production and service systems. Including ten advanced research papers and one development report, it covers a wide range of topics, including smart factories, logistics, distribution with value chains; product service systems; sustainable ecosystems with value in production and service industries; the sharing economy in production systems with cloud computing; the application of digital transformations in production and service systems.

All papers and reports were refereed through careful peer reviews with experts. The editors deeply appreciate the authors for their careful work and the reviewers for their invaluable efforts, without which this special issue would not have been possible. Finally, we hope this special issue provides valuable information to our interested readers and encourages further research on value creation in production.

The “process chain” concept for the integration of multiple manufacturing processes has been attracting attention in the field of manufacturing in recent years. In a number of specialized fields, laser-based processes in particular are actively being studied, as their high flexibility allows them to be used not only as individual manufacturing processes but also in combination to develop new ones.

Most of the practical laser technologies involve heat, which can be used for thermal processing to change surface properties or for removal processing. In recent years, lasers have also been used as a heat source for additive manufacturing, as well as ultra-short-pulsed lasers being applied to non-thermal processes.

This special issue features various studies and reports that present the latest advances as well as current challenges in laser-based/assisted manufacturing. It includes nine related papers that indicate the possibilities and future of new laser processing technologies.

We deeply appreciate all the authors and reviewers for their efforts and contributions, and we also hope this special issue will encourage further research on laser-based/assisted manufacturing.

The accuracy of a three-dimensional (3D) positioning system can ultimately be evaluated via measurement of a 3D vector between command and actual end-effector positions at arbitrary points over the entire workspace. This is a simple, yet challenging, metrological problem. The motion accuracy of a machine tool is traditionally evaluated on an axis-to-axis basis, with every error motion of every axis being independently measured as part of a one-dimensional measurement process in a different setup. Toward the ultimate goal of 3D position measurement over the entire workspace, research efforts have offered several new, practical measurement technologies.

This special issue covers the technical and academic efforts regarding the evaluation of machine tool accuracy. The papers in this special issue clarify the latest research frontiers regarding machine tool accuracy from a metrological viewpoint. In the first paper, by Montavon et al., error calibration technologies and their management are reviewed within the Internet of production concept. Long-term accuracy monitoring and management are clearly among the most crucial technical challenges faced regarding machine tools, and the work by Xing et al. is related to them. Ibaraki et al. presented machining tests to evaluate the thermal distortion of a machine tool. Peukert et al. studied the dynamic interaction between machine tools and their foundations. Various 3D measurement schemes for determining machine error motions have been investigated by many researchers, and some have been implemented in industrial applications. Kenno et al. and Florussen et al. investigated 3D measurement using the R-test for five-axis machines. Miller et al. studied simultaneous measurement of six-degree-of-freedom error motions of a linear axis. Nagao et al. presented an error calibration method for a parallel kinematic machine tool.

The editors appreciate the contributions of all the authors, as well as the work of the reviewers. We are confident that this special issue will further encourage research and engineering work for improving the accuracy and performance of machine tools.

The properties of a mechanical material depend not only on its chemical components but also on the micro/nano structures of its surface and interior. Attempts have been made in recent years to develop new surface/material functions through mechanical processes. For example, technologies to control various characteristics, such as friction, water repellency, and optical properties, have been developed by constructing micro/nano periodic structures on the surfaces of materials. Since these properties depend on the geometry of the surface morphology, micro/nano fabrication processes can produce a variety of properties. This indicates that the surface properties and material properties of portions of the materials can be controlled to reach optimal conditions required by machine product design. This technology is expected to lead to the advanced production of products integrating design, manufacturing, and materials in an organic way. Here, we call the materials and surfaces with their properties arbitrarily controlled in accordance with machine design “tailored functional materials and surfaces.”

This special issue features various studies and reports related to tailored functional materials and surfaces, and it includes 12 related papers and a review. They cover processing technologies that create and control various surface functions, such as water repellency, friction, biological and chemical reactions, and optical properties. They indicate the possibilities and future of new precision processing technologies.

We deeply appreciate all the authors and reviewers for their efforts and contributions. We also hope that this special issue will encourage further research on tailored functional surfaces.

The design of machine tools strongly depends on the materials chosen. Increasing requirements on machine tools require the joint optimization of material and design and thus also drive the development of new materials in this field. Digital technologies finally creating a digital shadow of the machine in development also enable the required co-development taking into consideration dynamic, thermal and long term influences and behavior, enabling state and health monitoring to increase the performance of the machine tool to the maximum possible. The choice of material for the different components of machine tools is today even more difficult than ever. The recent review paper by Möhring et al. [1] sheds light on the vast field of properties and decision opportunities of combining materials at hand with design features. In former times, cast iron was the predominant material for machine bodies and has left its footprints on the design of machine tool bodies lasting still up to now. Because massive machine bodies have been the wealth of good properties, high accuracy, stiffness, good material damping properties have been attributed to cast iron design, then with increasing strength requirements higher strength cast irons came into fashion having much less material damping and finally lead to welded frames. Today requirements of dynamics and thermal behavior change the scene again. The goal is to achieve high productivity with high accuracy, which typically is a contradiction. But increasing dynamics requires distinguishing between moving bodies and their non-moving counterparts, and opens the floor for multimaterial design. For moving parts, which have to move with high dynamics meaning, high speed, high acceleration, high jerk, light weight design prevailed with the utilization of standard materials. Because manufacturability plays a major role, the bionic structures have to be degraded to thin walled rib structures as demonstrated in Fig. 1, while in future additive manufacturing will remove that restriction and enable some real bionic structures.

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Multidisciplinary study and practice of high-precision engineering, metrology, and manufacturing have made a direct contribution to industrial and economic development in the world, providing new value creation and enhancing productivity and product quality. This special issue focuses on the latest studies in the field of precision engineering. The special issue especially features advanced technologies in the manufacturing process, metrology, machine tools, machine elements, and nano/micro mechanisms. Besides these technologies, to enhance reliability and safety in the production processes, there is a need for usability and functionality based on IoT-related technology, which is represented by Industrie 4.0 or the Industrial Internet. Therefore, many researchers have now begun to focus on cyber-physical production systems (CPPS), which can detect anomalies and self-optimize the production process by comparing actual results extracted from sensors and simulation results. From this viewpoint, advanced research related to CPPS, such as simulation-based technique, sensor-based technology, and in-depth understanding and modeling of the manufacturing process, is covered in this special issue.

In this special issue of IJAT, there are 14 research papers on precision-engineering-related topics as mentioned above. The papers, revised and extended according to the editors’ request, were originally presented at the 17th International Conference on Precision Engineering (ICPE2018), held in Kamakura, Japan, in 2018. We express our sincere thanks to the authors and reviewers for their meticulous work in helping publish this special issue. We hope these articles will encourage further research on precision engineering.

The demand for high-precision and high-efficiency machining of hard ceramics such as silicon carbide (SiC) for semiconductors and hardened steel for molding dies has significantly increased for power devices in automobiles, optical devices, and medical devices. Certain types of hard metals can be machined by deterministic precision-cutting processes. However, hard and brittle ceramics, hardened steel for molds, or semiconductor materials have to be machined by precision abrasive technologies such as grinding, polishing, and ultrasonic vibration technologies with diamond super abrasives. The machining of high-precision components and their molds/dies by abrasive processes is much more difficult owing to their complex and nondeterministic nature as well as their complex textured surface. Furthermore, high-energy processes with UV lasers and IR lasers, and ultrasonic vibration can be used to assist abrasive technologies for greater precision and efficiency. In this sense, precision grinding and polishing processes are primarily used to generate high-quality and functional components usually made of hard and brittle materials. The surface quality achieved by precision grinding and polishing processes becomes more important to reduce processing time and costs.

This special issue features seven research papers on the most recent advances in precision abrasive technologies for hard materials. These papers cover various abrasive machining processes such as grinding, polishing, ultrasonic-assisted grinding, and laser-assisted technologies.

We deeply appreciate the careful work of all the authors and thank the reviewers for their incisive efforts. We also hope that this special issue will encourage further research on abrasive technologies.

With the 2011 launch of Industrie 4.0, a German project aiming to promote the computerization of manufacturing, the integration of physical or actual manufacturing systems with cyber-physical systems (CPS) using various technologies, such as the Internet of things (IoT), industrial Internet of things (IIOT), and artificial intelligence, is considered to be more important than ever before. One of the goals of the Industrie 4.0 is to realize smart factories or smart manufacturing using advanced digital technologies. However, the core component in the manufacturing systems is still machine tools.

This special issue, composed of eleven excellent research papers, focuses on the latest research advances in machine tools and manufacturing processes. It covers various topics, including machine tool control, tool path generation for multi-axis machining, and machine tool components. Furthermore, this special issue includes innovative machining technologies, including not only cutting and grinding processes but also the EDM process and burnishing process connected effectively with force control techniques. All the research contributions were presented at IMEC2018, a joint event with JIMTOF2018, held in Tokyo, Japan in 2018.

The editors would like to sincerely thank the authors for their dedication and for their well written and illustrated manuscripts. We are also profoundly grateful for the efforts of all the reviewers who ensured their quality. Finally, we sincerely hope that studies on machine tools and related manufacturing technologies will further contribute to the development of our global society.

“Don’t automate, augment!”

This is the takeaway of the seminal book on the future of work by Davenport and Kirby.^*1 The emergence of cyber-physical systems makes radical new products and systems possible and challenges the role of humankind. Throughout the design, manufacturing, use, maintenance, and end-of-life stages, digital aspects (sensing, inferencing, connecting) influence the physical (digital fabrication, robotics) and vice versa. A key takeaway is that such innovations can augment human capabilities to extend our mental and physical skills with computational and robotic support – a notion called “augmented well-being.” Furthermore, agile development methods, complemented by mixed-reality systems and 3D-printing systems, enable us to create and adapt such systems on the fly, with almost instant turnaround times. Following this line of thought, our special issue is entitled “Augmented Prototyping and Fabrication for Advanced Product Design and Manufacturing.”

Heavily inspired by the framework of Prof. Jun Rekimoto’s Augmented Human framework,^*2 we can discern two orthogonal axes: cognitive versus physical and reflective versus active. As depicted in Fig. 1, this creates four different quadrants with important scientific domains that need to be juxtaposed. The contributions in this special issue are valuable steps towards this concept and are briefly discussed below.

AR/VR

To drive AR to the next level, robust tracking and tracing techniques are essential. The paper by Sumiyoshi et al. presents a new algorithm for object recognition and pose estimation in a strongly cluttered environment. As an example of how AR/VR can reshape human skills training, the development report of Komizunai et al. demonstrates an endotracheal suctioning simulator that establishes an optimized, spatial display with projector-based AR.

Robotics/Cyborg

Shor et al. present an augmentation display that uses haptics to go beyond the visual senses. The display has all the elements of a robotic system and is directly coupled to the human hand. In a completely different way, the article by Mitani et al. presents a development in soft robotics: a tongue simulator development (smart sensing and production of soft material), with a detailed account of the production and the technical performance. Finally, to consider novel human-robot interaction, human body tracking is essential. The system presented by Maruyama et al. introduces human motion capture based on IME, in this case the motion of cycling.

Co-making

Augmented well-being has to consider human-centered design and new collaborative environments where the stakeholders involved in whole product life-cycle work together to deliver better solutions. Inoue et al. propose a generalized decision-making scheme for universal design which considers anthropometric diversity. In the paper by Tanaka et al., paper inspection documents are electronically superimposed on 3D design models to enable design-inspection collaboration and more reliable maintenance activities for large-scale infrastructures.

Artificial Intelligence

Nakamura et al. propose an optimization-based search for interference-free paths and the poses of equipment in cluttered indoor environments, captured by interactive RGBD scans. AR-based guidance is provided to the user.

Finally, the editors would like to express their gratitude to the authors for their exceptional contributions and to the anonymous reviewers for their devoted work. We expect that this special issue will encourage a new departure for research on augmented prototyping for product design and manufacturing.

^*1 T. H. Davenport and J. Kirby, “Only Humans Need Apply: Winners and Losers in the Age of Smart Machines,” Harper Business, 2016.

^*2 https://lab.rekimoto.org/about/ [Accessed June 21, 2019]

Additive manufacturing (AM) with metals is currently one of the most promising techniques for 3D-printed structures, as it has tremendous potential to produce complex, lightweight, and functionally-optimized parts. The medical, aerospace, and automotive industries are some of the many expected to reap particular benefits from the ability to produce high-quality models with reduced manufacturing costs and lead times. The main advantages of AM with metals are the flexibility of the process and the wide variety of metal materials that are available. Various materials, including steel, titanium, aluminum alloys, and nickel-based alloys, can be employed to produce end products.

The objective of this special issue is to collect recent research works focusing on AM with metals. This issue includes 5 papers covering the following topics:

– Powder bed fusion (PBF)

– Directed energy deposition (DED)

– Wire and arc-based AM (WAAM)

– Binder jetting (BJT)

– Fused deposition modeling (FDM)

This issue is expected to help readers understand recent developments in AM, leading to further research.

We deeply appreciate the contributions of all authors and thank the reviewers for their incisive efforts.

Precision surface finishing plays an important role in product quality owing to its direct effects on product appearance. As a result, automated precision surface finishing processes (APSFPs) are key technologies for industrial products and molds for forming and shaping processes. APSFPs can be divided into three main categories, namely, mechanical processes, electrochemical processes, and high energy beam processes. The objective of this special issue is to collect the cutting-edge research works focused on APSFPs. This issue includes 11 papers on APSFPs covering the following topics:

– Review of ultraprecision surface finishing processes.

– Ultraprecision surface machining and finishing with compensated feeding mechanisms.

– Ultrasonic assisted cutting of unidirectional wetting surfaces and polishing of mold steels.

– Vibration-assisted polishing of glass lenses.

– Magnetic-assisted polishing of mirror surfaces.

– Chemical-mechanical polishing of single-crystal SiC and GaN wafers.

– Direct transfer of smoothing Au surfaces.

– Plasma surface finishing of narrow channel walls of X-ray crystal monochromators.

– Analysis and characterization of finished surfaces.

It is expected that this issue will be helpful for readers to understand the recent developments in APSFPs and will lead to further research on APSFPs.

We deeply appreciate the contributions of all authors and thank the reviewers for their incisive efforts.

Cutting technologies have been widely applied in the manufacturing of airplane, automobile, medical, energy, and information industries. Cutting operations are generally evaluated in terms of material removal rates and surface quality. Materials science and engineering has also made significant progress in improving material properties. Therefore, scientific research should be conducted to achieve high performance when working with difficult-to-cut materials such as nickel-based super alloy. Because the manufacturing of products with complex shapes in various industries requires multi-axis machining, the cutting operations should be managed efficiently through controls, simulations, and monitoring.

This special issue was organized by Research Committee of Cutting Technologies in Japan Society for Precision Engineering. This issue includes 14 papers on advanced cutting technologies covering the following topics:

– Modeling the tribological aspects of the tool face–workpiece interface during the cutting process.

– Cutting mechanics in advanced cutting operations.

– Tool wear and coolant supply in cutting of advanced materials.

– Cutting processes for hard materials to improve cutting performance.

– Fixturing, chatter suppression, and tool path generation to control cutting processes and operations.

– Surface characterization and modeling to control product quality in multi-axis machining.

I hope this issue will be helpful for readers to understand cutting processes and improve the cutting operations.

This is the fourth special issue on design and manufacturing for environmental sustainability. While Japanese manufacturers are not so active in this field, the trend of integrating sustainability into manufacturing activities and management of companies is becoming dominant. We can point out three epoch-making instances: namely, United Nations’ ‘Sustainable Development Goals (SDGs),’ which consists of 17 goals to be achieved by 2030, covering not only environmental sustainability but also social and human sustainability; EU’s ‘Circular Economy,’ which promotes various routes for resource circulation (e.g., reuse, remanufacturing, maintenance, and recycling) for increasing employment and market competitiveness of EU and resource efficiency; and ‘Paris Agreement’ on climate change, which enforces reduction of the emission of greenhouse gases to zero by the end of this century.

This special issue includes six well-written papers, all of which are deeply related to these three policies. The first four papers focus on product life cycle or even multiple product life cycles. This aspect is an inherent feature of design and manufacturing for environmental sustainability, which was not considered in traditional design and manufacturing. The keywords of these four papers are life cycle CO₂ emission evaluation of electric vehicles, life cycle simulation of reuse among multiple product life cycles, disassembly part selection based on the idea of life expectancy, and personalization design aiming at avoiding mass production and mass disposal. The latter two papers are rather fresh in this journal. The fifth paper deals with customer preferences in Indonesia. Focusing on life styles in developing countries is a very important topic emphasized in SDGs. The last paper deals with food waste, which is emphasized in both SDGs and Circular Economy.

Most of the papers, revised and extended in response to the editor’s invitations, were originally presented at EcoDesign 2017: the tenth International Symposium on Environmentally Conscious Design and Inverse Manufacturing, held in Tainan, Taiwan.

The editor sincerely thanks the authors and reviewers for their devoted work in making this special issue possible. We hope that these articles will encourage further research on design and manufacturing for environmental sustainability.

The demand for high-precision hard components and their molds/dies have increased in various industries such as in the optical, automotive, and communication industries, as well as in life and medical sciences. Some difficult-to-machine materials can be reliably machined using deterministic precision cutting processes. On the other hand, hard and brittle materials such as ceramics, carbides, hardened steel of molds, glassy materials, or semiconductor materials have to be machined using precision abrasive technologies with super abrasives of diamond or cBN. However, the machining of high-precision components and their molds/dies by abrasive processes, is much more difficult because of their complex and non-deterministic nature and textured surface. Furthermore, high-energy processes such as laser technology can assist abrasive technologies for ensuring higher precision and efficiency. In this sense, precision grinding and polishing process are primarily used to generate high-quality and functional components usually made of difficult-to-machine materials. The surface quality achievable by precision grinding and polishing processes becomes more important for reducing machining time and costs.

This special issue features five research articles – five papers – related to the most recent advances in precision abrasive technology of difficult-to-machine materials. Their subjects cover various abrasive machining processes of grinding, polishing, abrasive flow machining, tooling technology, and laser technologies.

We deeply appreciate the careful work of all authors and thank the reviewers for their incisive efforts. We also hope this special issue will trigger further research on abrasive technologies.

Automation of machine tools has made them more productive, thereby providing an advantage for sustainability and the welfare of mankind. However, in many cases, the successful automation of machine tools requires the avoidance of self-excited chatter vibrations, resulting in a reliable stable state for cutting. Machine tool operators tend to use the machines close to their power thresholds, thereby unknowingly driving them toward the limits of their stability. Much progress has been made in the last few decades concerning the understanding and prediction of such vibrations, and this has led to improvements such as higher cutting rates and chip thicknesses.

Several countermeasures such as active and passive damping are available for avoiding chatter vibrations in machine tools. However, their industrial use is not common yet. In fact, the industry is somewhat unfamiliar with many of these countermeasures. The hesitant attitude of the machine tool builders to apply such countermeasures is a result of several factors: active and passive damping devices are additional system components that require design, tuning, and maintenance. Furthermore, they are associated with a risk of failure, resulting in additional down times of the machines. Additionally, if a machine requires such devices to achieve the desired specifications, the customer’s opinion regarding it can be negatively affected. This situation is challenging for machine tool builders, users, and academia as well. Therefore, we decided to dedicate a special issue of IJAT to this topic.

This special issue focuses on both active and passive damping measures, particularly the measures that are systematically designed and deliberately implemented to increase the chatter-free depth of cut in machine tools. The papers in this issue identify successful applications or at least a vision for them. Additionally, models demonstrating the effects of the chosen active or passive damping systems are presented. Some of these models can also be used to systematically select the parameters of the system. Some of the systems can be easily applied as low-cost patch-up solutions to improve the behaviors of the machines already in use.

I hope that this special issue delivers a valuable overview of the existing approaches to introduce additional damping in machine tools. I would like to sincerely thank all the authors for their dedication and the well written and illustrated manuscripts. I would also like to thank the reviewers for their efforts to ensure the quality of this issue. Finally, I am very thankful to IJAT for their immense cooperation and support. I wish you all the best and hope that you can benefit from the content of this special issue.

First, we would like to express our sincere condolences to the victims of the landslides and floods caused by the torrential rain in Japan in July 2018. We were terribly grieved to hear about these disasters during the editing of this special issue of the International Journal of Automation Technology (IJAT), and we sincerely hope for the revival of the disaster-stricken areas.

This special issue focuses on the progress in manufacturing technologies for maximizing product quality and reducing costs, especially in the mechanical industry. Manufacturing technologies have been developing in order to meet the changes in social and economic environments such as progress in informatization, diverse needs, and increasing demands for a sustainable society. At present, engineers and researchers in the field of manufacturing are facing an unprecedented rapid change caused by the fourth industrial revolution. Therefore, research in this field is also expected to develop more than ever before.

This special issue of IJAT contains seven research papers on topics including shearing of metal sheets, machine tools and machining technology, precision dimensional measurement, and nanoimprinting process. Some of the papers, revised and extended at the editors’ request, were presented originally at the 9th International Conference on Leading Edge Manufacturing in 21st Century (LEM21), held in Hiroshima, Japan in 2017.

The editors thank the authors and reviewers for their comprehensive efforts in making this special issue possible, and hope that these articles will encourage further research on manufacturing technologies.

To solve problems underlying design and manufacturing we often rely on methodologies of computational intelligence such as machine learning, artificial neural networks, fuzzy logic, fuzzy inference systems and smart optimization algorithms. In this Special Issue of the International Journal of Automation Technology, original articles are presented with reference to the engagement of intelligent computation in diverse application areas of design and manufacturing, including manufacturing process monitoring, manufacturing systems management, scheduling, design theory and methodology.

The six research papers in this Special Issue propose the use of intelligent computation methodologies to deal with various topics related to manufacturing and design. In particular, the first three papers focus on manufacturing process monitoring with reference to different manufacturing technologies, including tool wear monitoring in drilling of composite materials, sensor monitoring in CNC turning and residual stress prediction in welding. Diverse intelligent approaches such as artificial neural networks and adaptive neuro-fuzzy inference systems are proposed to support manufacturing process monitoring. The fourth paper deals with the manufacturing system level, proposing the employment of a solution algorithm combining metaheuristics and operation simulation for scheduling of production processes. The fifth paper aims at developing tools to guide the manufacturers to manage the technology investment and cost saving target for customer satisfaction based on the application of internet of things. The last paper proposes a methodology to support the introduction of customer requirements in product and service design via a decision support system which exploits artificial intelligence algorithms (machine learning) based on inductive inference, allowing knowledge related to product/service to be mapped, structured and managed to design the service and product semantic model.

The editors deeply appreciate all the authors and anonymous reviewers for their effort and excellent work to make this Special Issue unique. We hope that future research on intelligent computation in manufacturing and design will advance manufacturing technology and systems as well as design methodologies.

To solve problems underlying design and manufacturing we often rely on methodologies of computational intelligence such as machine learning, artificial neural networks, fuzzy logic, fuzzy inference systems and smart optimization algorithms. In this Special Issue of the International Journal of Automation Technology, original articles are presented with reference to the engagement of intelligent computation in diverse application areas of design and manufacturing, including manufacturing process monitoring, manufacturing systems management, scheduling, design theory and methodology.

The six research papers in this Special Issue propose the use of intelligent computation methodologies to deal with various topics related to manufacturing and design. In particular, the first three papers focus on manufacturing process monitoring with reference to different manufacturing technologies, including tool wear monitoring in drilling of composite materials, sensor monitoring in CNC turning and residual stress prediction in welding. Diverse intelligent approaches such as artificial neural networks and adaptive neuro-fuzzy inference systems are proposed to support manufacturing process monitoring. The fourth paper deals with the manufacturing system level, proposing the employment of a solution algorithm combining metaheuristics and operation simulation for scheduling of production processes. The fifth paper aims at developing tools to guide the manufacturers to manage the technology investment and cost saving target for customer satisfaction based on the application of internet of things. The last paper proposes a methodology to support the introduction of customer requirements in product and service design via a decision support system which exploits artificial intelligence algorithms (machine learning) based on inductive inference, allowing knowledge related to product/service to be mapped, structured and managed to design the service and product semantic model.

The editors deeply appreciate all the authors and anonymous reviewers for their effort and excellent work to make this Special Issue unique. We hope that future research on intelligent computation in manufacturing and design will advance manufacturing technology and systems as well as design methodologies.

Recently, terrestrial laser scanners have been significantly improved in terms of accuracy, measurement distance, measurement speed, and resolution. They enable us to capture dense 3D point clouds of large-scale objects and fields, such as factories, engineering plants, large equipment, and transport ships. In addition, the mobile mapping system, which is a vehicle equipped with laser scanners and GPSs, can be used for capturing large-scale point clouds from a wide range of roads, buildings, and roadside objects. Large-scale point clouds are useful in a variety of applications, such as renovation and maintenance of facilities, engineering simulation, asset management, and 3D mapping. To realize these applications, new techniques must be developed for processing large-scale point clouds. So far, point processing has been studied mainly for relatively small objects in the field of computer-aided design and computer graphics. However, in recent years, the application areas of point clouds are not limited to conventional domains, but also include manufacturing, civil engineering, construction, transportation, forestry, and so on. This is because the state-of-the-art laser scanner can be used to represent large objects or fields as dense point clouds. We believe that discussing new techniques and applications related to large-scale point clouds beyond the boundaries of traditional academic fields is very important.

This special issue addresses the latest research advances in large-scale point cloud processing. This covers a wide area of point processing, including shape reconstruction, geometry processing, object recognition, registration, visualization, and applications. The papers will help readers explore and share their knowledge and experience in technologies and development techniques.

All papers were refereed through careful peer reviews. We would like to express our sincere appreciation to the authors for their submissions and to the reviewers for their invaluable efforts for ensuring the success of this special issue.

Since the transistor was invented at Bell Laboratories in 1947 and the concept of the integrated circuit was presented by Jack Kilby of TI in 1958, devices using silicon semiconductors have been developed with tremendous drive. Today, ultrastructural, highly dense, and high-functional ULSI devices have become a reality. Accordingly, novel, three-dimensional devices that aim at multiple functions and high performance have been proposed, and novel materials have come into existence. As Artificial Intelligence (AI) has drawn increasing attention, the concept of “Singularity,” or singular technical point, has become a focus of great attention. Singularity is a prediction put forth by American futurist Ray Kurzweil, who said, “Singularity will come in 2045, when the speed of the evolution of technology will become infinite and Artificial Intelligence will exceed human intelligence.” This prediction is said to have its roots in “Moore’s law,” formulated by Intel founder Gordon Moore, which states that “the degree of integration of transistors doubles every year and a half.” The deep learning and self-learning functions of computers can be mentioned as significant driving factors behind the dramatic development of AI studies. The processing capacity of AI has increased exponentially owing to the evolution and combination of various technologies, and the speed of development of technology now far exceeds the biological limits of humankind. As a result, it is inevitable that “Singularity” will come to pass, and the technologies behind semiconductor devices contributing to the arrival of Singularity are expected to develop much further.

In the process of such semiconductor development, silicon carbide (SiC), among other materials, came to be expected as the next-generation semiconductor in the 1950s, but it could not succeed significantly as a practical device. SiC also attracted attention as the material used in green and red light-emitting elements. In the 1990s, SiC came into the spotlight, along with gallium nitride (GaN) crystal and other materials, by being put into practical use as the material used in blue light-emitting diodes. Today, as the silicon (Si) as power devices have already approached the physical limits of the material, next-generation devices focus on semiconductor substrates such as SiC and GaN, which have performance indexes tens to thousands of times higher than the Si semiconductor. Especially, high-power devices and high-frequency devices have attracted special attention, because the use of semiconductor devices in the automotive and other fields has increased dramatically. Furthermore, the single-crystal substrate of semiconducting diamond is considered to be the ultimate semiconductor device, so this topic has been vigorously researched.

The above-mentioned next-generation devices are called green devices because they could reduce power consumption and carbon dioxide emissions tremendously, leading to the realization of a low-carbon and energy-saving society. Such devices are utilized not only as high-power semiconductors and light-emitting semiconductors but also as various sensors, including gas sensors and UV sensors, as well as MEMS devices. Further application of such devices is expected in the future.

To actually produce the high-performance and multifunctional green devices, it will be necessary to establish the technologies for device integration and the manufacturing process. An example would be the process of growing crystals that are larger in diameter and higher in quality. The substrate materials applied in such technologies, including SiC, GaN, and diamond, are known as ultra-hard-to-process materials: their extreme mechanical and chemical stability makes the general manufacturing process much more difficult. A breakthrough is needed to solve this problem. Many challenges must be overcome systematically to produce a high-performance green device, as the device to which such crystalline materials are applied will reduce power consumption and carbon dioxide emissions extremely effectively.

This special issue focuses on manufacturing processes, including the planarization processing of every kind of hard-to-process crystal substrate, involved in producing green devices, sensors, etc. And the paper on the various applications of the device are published in this issue. This issue is expected to contribute to the establishment of a process for manufacturing green devices, which is an essential industrial strategy, as well as to future intensive studies in this field.

Sensors, which are transducer-type devices, are indispensable to today’s advanced information society. A huge number of sensors are used not only in everyday devices but also in advanced industrial systems. They are used in Internet of things (IoT) services to gather external information, intelligent robots to recognize the world around them and control their movements, and all advanced vehicle technologies to operate safely and automatically. Sensors detect light, motion, force, fluid flow, electric/magnetic fields, and other physical, chemical, and biological aspects of the external environment.

To improve the performances of these sensors, such as their sensitivity, sensing resolution, and power consumption, extensive R&D is conducted in industry and academia. Recent technological progress in MEMS technology has allowed sensors to be manufactured on scales that are increasingly microscopic. More recently, the extreme downsizing of structures to nanometer scale has led to innovative sensing devices called NEMS.

This special issue addresses the latest research advances in nanosensing and microsensing science and engineering. It covers a wide range of topics, including novel sensing devices and technologies; small structures fabrication technologies for sensors; MEMS/NEMS sensing devices; physical, chemical, optical and biological sensing devices; and nanoscale science and engineering for sensors.

All papers were refereed through careful peer reviews. We would like to express our sincere thanks to the authors for their submissions and to the reviewers for their invaluable efforts. Lastly, we hope this special issue provides valuable and useful information to our interested readers and researchers.