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Advanced manufacturing research for sustainable battery life cycles is of utmost importance to reach net zero carbon emissions (European Commission, 2023a) as well as several of the United Nations Sustainable Development Goals (UNSDGs), for example: 30% reduction of CO2 emission, 10 million job opportunities and access to electricity for 600 million people (World Economic Forum, 2019). This editorial paper highlights international motivations for pursuing more sustainable manufacturing practices and discusses key research topics in battery manufacturing. Batteries will be central to our sustainable future as generation and storage become key components to on-demand energy supply. Four underlying themes are identified to address industrial needs in this field: 1. Digitalizing and automating production capabilities: data-driven solutions for production quality, smart maintenance, automation, and human factors, 2. Human-centric production: extended reality for operator support and skills development, 3. Circular battery life cycles: circular battery systems supported by service-based and other novel business models, 4. Future topics for battery value chains: increased industrial resilience and transparency with digital product passports, and next-generation battery chemistries. Challenges and opportunities along these themes are highlighted for transforming battery value chains through circularity and more sustainable production, with a particular emphasis on lithium-ion batteries (LIB). The paper concludes with directions for further research to advance a circular and sustainable battery value chain through utilizing the full potential of digitalization realising a cleaner, more energy-efficient society.

This study aims to experimentally confirm whether knowledge that has been challenging to transfer through traditional on-the-job training (OJT) can be effectively transferred by introducing a formalized OJT approach that describes the improvement process knowledge of skilled production systems consultants, facilitating imitation by unskilled consultants. We adopted the Digital Triplet (D3) concept, an extension of the authors’ digital twin framework to intelligent activities, aligning with our study objectives. Recognizing the difficulty and inadequacy of knowledge transfer in production systems consulting OJT, we propose an OJT support method integrating a decision-making modeling approach for skilled consultants’ processes based on the Generalized Production Systems Consulting Process Model (GCPM) from prior literature into traditional OJT methods involving self-learning and direct instruction. This method enables the construction of a domain-specific GCPM, formalizing the improvement process flow implemented by skilled consultants and linking it to production improvement expertise and tools. In a case study focused on energy-saving improvement, we constructed and tested a domain-specific GCPM’s efficacy in facilitating the transfer of difficult-to-transfer knowledge. The results indicate that domain-specific GCPM facilitates such knowledge transfer, including specialized improvement, knowledge utilization, rationale, and adaptation to specific cases.

To support engineers in solving engineering problems utilizing digital twin, we are proposing ‘digital triplet’ concept. We are also developing a problem-solving process support method by using the Log Level Description (LLD) that describes an executed problem-solving process and the Generic Process Model (GPM) that describes a generalized and prescriptive process. This paper illustrates a support method for describing LLDs to put the proposed method into practical use. Through an attempt to describe LLDs, three time-consuming operations were identified: viz., interviewing, structuring the information, and relating each action with the GPM. To save the labor of these operations, we propose the method that the engineer who executes the process sequentially describes the LLD by oneself based on the GPM. This paper also illustrates an LLD description support system based on the proposed method. Finally, a case study was conducted to describe the actual fault detection system design processes with the developed support system. By comparing the LLDs created with the support system in the case study with the ones created manually, the effectiveness of the proposed method was discussed. In addition, by interviewing engineers who created the LLDs in the case study, the usefulness and feasibility of the proposed method were discussed.

“Digital Triplet” is a concept proposed to support manufacturing system engineers by combining the knowledge and know-how of expert engineers with digital technology. This study proposes a method to represent engineering processes executed by engineers in a reusable manner based on Digital Triplet. Specifically, we develop a procedure to create a "log-level description" that records an engineering process as it is and a “generalized process model” that generalizes multiple log-level descriptions, using a process modeling language named “PD3” (Process Modeling Language for Digital Triplet). In a case study, expert engineers first executed engineering processes to improve production speed on a simplified production line. Next, log-level descriptions and a generalized process model were created for the engineering processes by the proposed procedure. Furthermore, an experiment was conducted on novice engineers using the generalized process model, and the results suggested that the model is effective for education. Currently, creating log-level descriptions or generalized process models is a labor-intensive task as it is done manually based on the subjective judgment of the person representing the processes. However, we showed the application of "process mining" techniques has the potential to partially automate the task of creating the models.

The application of a cyber physical system (CPS) in a production system to improve the efficiency and effectiveness of its operation is called a cyber physical production system (CPPS). A digital twin (DT) is widely regarded as a cornerstone for the realization of CPPS, and many tools, methods and guidelines for developing DT have been proposed in recent years. However, DT alone is not sufficient for solving practical problems that occur in actual production systems (e.g., frequent rescheduling caused by unpredictable events, such as machine failure or engineering changes). Because DT is a digital representation of a physical object, it cannot individually provide a problem-solving procedure for unpredicted situations. Therefore, the integrated utilization of human experts’ knowledge with DT is indispensable for the realization of CPPS. This paper proposes a systematic method for acquiring experts’ knowledge that can be integrated with a DT to construct a production system that is robust against unpredicted changes in a production environment. In particular, the study focuses on the knowledge acquisition for the high-mix and low-volume production scheduling problem. This is because quick modification of the existing schedule considering complicated constraints among processes, resources, delivery time and so forth is regarded as a typical problem that only human experts can solve. Through a case study in the die machining industry, this study demonstrates the validity and limitations of the method and concludes that the proposed method is effective for acquiring experts’ knowledge.

We aimed to clarify expert skills in refinery patrol inspection using data collected through a virtual reality experimental system. As body positioning and postural changes are relevant factors during refinery patrol inspection tasks, we measured and analyzed both visual attention and head positioning behavior among experts and “knowledgeable novices” who were engaged in the engineering of the refinery but had less inspection experience. The participants performed a simulated inspection task, and the results showed that 1) expert inspectors could find more defects compared to knowledgeable novices, 2) visual attention behavior was similar between knowledgeable novices and experts, and 3) experts tended to position their heads at various heights and further from the inspection target to obtain visual information more effectively from the target compared to knowledgeable novices. This study presented the differences in head positioning behavior between expert and novice inspectors for the first time. These results suggest that to evaluate the skills used in inspecting relatively larger targets, both visual attention and head positioning behavior of the inspectors must be measured.

This study aims to analyze the process flow of skilled consultants who utilize production improvement know-how and digital technology to enhance production systems in external companies. The concept of a Digital Triplet (D3), which expands the authors’ Digital Twin framework to include the intelligent activity world, is adopted as it aligns with this study’s objective. Given the complexity of the problems faced by production system consulting and the resulting inadequacy of reusing decision-making processes of skilled engineers based on the Generalized Process Model (GPM) using D3, a production system consulting modeling method is proposed. This method incorporates the Generalized Production System Consulting Process Model (GCPM) to generalize the production system consulting process. Using the proposed method, a case study focusing on energy-saving improvements was conducted to describe and analyze the consulting process of skilled consultants. The results show that the proposed method effectively captures the process flow of skilled consultants while considering the iterative structure of the GCPM. Additionally, utilizing the GCPM enables a comprehensive view of the entire process, facilitating an understanding of how knowledge and tools are utilized in various contexts.

Since the current manufacturing paradigm cannot get out of the mass production and mass consumption in correspondence with diversification and expansion of customer needs, today's manufacturing industry causes many problems such as sustainability issues typified by SDGs. The conventional design theory seems not to be sufficient for these problems because it does not deal with temporal changes of design objects. For solving this issue, we study “timeaxis design,” which explicitly deals with temporal changes in design. This paper proposes a timeaxis design (TaD) support method using patterns between temporal changes and countermeasures. First, we extract patterns of temporal changes and countermeasures to them from collected TaD cases. Next, we propose a TaD support method using these patterns. Finally, this paper illustrates timeaxis design of bicycle as a case study using the design support method. The TaD support method enables designers to design a product with introducing countermeasures against plausible temporal changes into design objects. The case study indicates that designers can find out TaD design solutions systematically using the proposed method.

In the context of recent servitization of manufacturing characterized by IoT, Big data, and AI, we require a data-driven front-loading design of product with service. This paper proposes a design method of service system that encourages co-creation using a structural framework called TriCyPSS (Triple Cycles for Product Service System) from the viewpoints of service chain and continuous provision among client business, my business, and partner business. This paper shows a case study according to the method’s procedure and details notations using a system modeling method called i* (eye-star). Using them, we clarify value in use brought by the service chain and continuous provision as well as data utilization and information circulation. Finally, this paper employs the method together with business planning methods and tools for practical use.

To avoid back injuries, caregivers are advised to use transfer-aid equipment while transferring a patient from a bed to a wheelchair. Although the usage of such equipment has been recommended for several decades, it remains unpopular in several countries, including Japan. The current study investigates the feelings of caregivers regarding the usage of transfer-aid equipment, the cause of their feelings, and the measures that can be considered in order to increase the acceptance of transfer-aid equipment by the extensive caregiver community. The relations among the movements of users (caregivers and patients) and impressions of the caregivers regarding the equipment, while monitoring the usage of the equipment, were analyzed using Kansei engineering. The relations revealed six distinct feelings that are related to users’ movements while using the equipment.

Manufacturing industry is required to transform itself into sustainable form. For this task, drawing images of sustainable manufacturing through developing a “scenario” is a hopeful means. When developing a scenario, the developers draw several future visions and transition paths qualitatively and quantitatively. However, scenario development is difficult and exhaustive task. In order to tackle this problem, referring the ideas of design engineering, we propose a framework of “scenario design” and develop a computational support method for scenario design. Based on this, we proposed a computable scenario model and a scenario design process. The proposed model includes sub models expressing intermediate states between the motivation for developing scenario and a documented scenario. We proposed a scenario design process includes four steps in which the scenario is designed in stepwise manner. In the first step, the designers clarify the objective, backgrounds, and outline of the scenario as a whole. In the second step, the designers determine the scenario structure, the number and outlines of sub scenarios. In the third step, the designers elaborate the details of the scenario qualitatively and quantitatively. At last in the fourth step, the result of the scenario design is documented for outreach activities. We implemented a backcasting scenario design support method proposed in a previous study on the design model and the design process. We developed a backcasting scenario design support system. As a case study, we designed Sustainable Manufacturing Scenario with the proposed method and the support system, in which economically and environmentally sustainable futures of Japanese manufacturing industry is envisioned. Through the case study, the effectiveness of the proposed design method and the support system is verified.

Fuel cell cogeneration is one of promising energy-saving technologies in pursuit of a sustainable society. However, it is unpredictable how many fuel cell cogeneration systems will be diffused since there are many future uncertainties, such as people's lifestyles and national energy policies. As an approach to tackling with this problem, this paper proposes a method for describing scenarios to analyze the diffusion of residential energy systems, such as fuel cell cogeneration systems. We develop a simulation model for estimating the diffusion of residential energy systems, in which conjoint analysis is undertaken to analyze consumers' preferences. In a case study, several scenarios are described for analyzing the diffusion of solid oxide fuel cell (SOFC) cogeneration systems for apartment houses, where the region of interest is Kansai Area, Japan from 2013-2030. The described scenarios differ in terms of nuclear energy policies. The results show that the number of fuel cell cogeneration systems in 2030 reaches 147-157 thousands depending on the share of nuclear power. In addition, it is revealed that monthly utility cost has a much larger impact on SOFC diffusion than CO2 emissions. Future work includes further what-if analyses of the scenarios to identify factors that would give a significant influence on SOFC diffusion.

This paper proposes a design method for dismantling a product by adding split-lines to the product. This method aims at extracting target components for their reuse, recycling, and proper disposal. The split-lines enable to destruct a product into desired shapes, like pull tabs of cans and caps of PET bottles. The proposed design method supports a designer in determining split-lines to extract a target component. This method classifies the components of the product into shells that surround the target component and finds out the areas in which split-lines can be added for each shell. Then the method finds out candidates of dismantling sequences with split-lines from the candidates of each shell's split-lines. A case study shows that the dismantling of a LCD TV with split-lines reduces the number of manual operations needed for extracting a target component.

Plastic materials are widely used for automotive parts, electronic devices, and faucet parts because they are lighter than metals and have superior workability and productivity. However, due to their poor weather resistance, their surfaces must be painted or plated. As a pretreatment for plating, it is most important to roughen the surface to obtain strong adhesion through an anchor effect. The conventional method is to use chemicals, but the use of chemicals is now severely restricted by the REACH regulation in the EU due to the environmental impact of wastewater and effluent treatment. We have obtained the same or higher adhesion strength than conventional methods by using a pretreatment method with ozone fine bubbles, which has almost no environmental damages. [ABSTRACT FROM AUTHOR]