Leveraging 3D Printing for Resilient Disaster Management in Smart Cities

Highlights

What are the main findings?

• 3D printing offers fast, accurate, and efficient manufacturing for smart cities.
• The process presents an opportunity to improve urban resilience, sustainability, and adaptability.

What is the implication of the main finding?

• Overcoming a high initial cost, solving regulatory problems, and training skilled operators are necessary.
• With the evolution of 3D and smart cities, resilient, efficient, and sustainable urban environments will be built.

Abstract

This work explores the transformative impact of 3D printing technology and disaster management within the context of smart cities. By evaluating various 3D printing technologies, such as desktop and large-scale printers, this research highlights their application in rapidly producing customized structures and essential supplies infrastructure components. Methods included the review of existing technologies, practical application in disasters scenarios. and the analysis of community engagement programs that enhance local preparedness and resilience through 3D printing. Case studies illustrate the significant benefits of integrating 3D printing technologies in disaster management. Findings indicate that while 3D printing offers rapid production and efficiency, disabilities such as high initial cost, regulatory issues, and the need for skilled operators must be addressed. This study concludes that with strategic collaboration and investment in the education and regulatory frameworks, 3D printing can significantly enhance urban resilience and sustainability, making it an invaluable tool for future smart cities. This research underscores the potential of 3D printing to significantly aid disaster management practices, fostering more adaptive and efficient urban environments.

1. Introduction

In recent years, the rapid advancements in technology have shown great potential towards providing innovative solutions in disaster management, particularly in the emerging field of smart cities. Among these innovations, rapid prototyping/3D printing stands out as a transformative tool that exhibits the potential to alter the way emergency response and disaster management are conducted [1]. The ability to swiftly produce customized, essential items on demand offers unparalleled flexibility and responsiveness, addressing critical needs in real time during disaster scenarios. This work explores the significant role of 3D printing in enhancing the efficiency, adaptability, and overall effectiveness of disaster management in smart cities, emphasizing its contributions across various aspects of emergency response [2,3].

According to the United Nations Sustainable Development Goals (UN SDGs), a “smart city” is an urban area that integrates digital technology and data-driven solutions to enhance performance, wellbeing, and quality of life while ensuring sustainability, inclusivity, and resilience [4]. These cities utilize advanced technologies to improve urban infrastructure, optimize resource management, and deliver efficient public services, thus addressing the challenges of rapid urbanization and environmental degradation [5]. Smart cities focus on reducing energy consumption, minimizing environmental impact, and fostering economic growth by promoting innovative practices and sustainable development [6]. They emphasize the active participation of citizens in governance through transparent, inclusive decision-making processes, ensuring that the benefits of smart technologies are equitably distributed [7,8]. This approach aligns with several UN SDGs, particularly those related to sustainable cities, communities (SDG 11), industry innovation, infrastructure (SDG 9), and climate action (SDG 13), by promoting urban environments that are economically viable, socially inclusive, and environmentally sustainable [9,10,11].

In the aforementioned context of United Nations Sustainable Development Goals (UN SDGs), smart cities “Disaster Management” refers to the systematic approach to preventing, preparing for, responding to, and recovering from disasters to mitigate their impact on human life, infrastructure, and the environment [11,12]. Disaster management in smart cities integrates advanced technologies and data analytics to enhance the efficiency and effectiveness of emergency response and recovery operations. This includes the use of real-time data, early warning systems, and communication networks to anticipate and respond to natural and manmade disasters [13]. It also involves the development of resilient infrastructure and the promotion of community preparedness and resilience. By leveraging technology, smart cities aim to minimize the adverse effects of disasters, ensure quick recovery, and maintain sustainable development [14]. This aligns with several UN SDGs, particularly those related to sustainable cities, communities (SDG 11), climate action (SDG 13), and partnerships for the goals (SDG 17), by fostering resilient, adaptive urban environments that can withstand and quickly recover from disaster events [15,16]. Figure 1 depicts the aforementioned SDGs, as set by the United Nations, that are relevant to the context of the paper.

Smart cities, characterized by the integration of advanced technologies to improve urban living, are increasingly adopting 3D printing as a cornerstone of their disaster management strategies [17,18]. The rapid production capabilities of 3D printing technology enable the swift creation of bespoke solutions tailored to the specific demands of emergency situations. This flexibility is crucial in mitigating the impact of disasters, as it allows for the immediate provision of necessary tools, medical supplies, and infrastructure components [19]. Furthermore, the deployment of 3D printers in proximity to disaster sites significantly reduces the time and costs associated with transporting critical supplies from distant locations, thereby expediting relief efforts [20].

One of the key advantages of 3D printing in disaster management is its adaptability to evolving conditions. Designs can be quickly adjusted based on real-time feedback and emerging needs, ensuring that the produced items are precisely suited to the dynamic requirements of disaster scenarios [21,22]. The versatility of 3D printing materials, ranging from plastics and metals to composites, further enhances its applicability, allowing for the production of a wide variety of items [23]. From lightweight medical tools to robust structural components, the range of applications is extensive and impactful [24,25].

This review looks into specific examples of how 3D printing has been utilized in crisis situations, highlighting its role in producing medical supplies and equipment, constructing shelter, housing, and facilitating tools and infrastructure repair [26]. In the medical domain, 3D printing has demonstrated its potential by enabling the rapid production of prosthetics, orthotics, and essential medical tools. During the COVID-19 pandemic, for instance, 3D printing was instrumental in addressing shortages of personal protective equipment (PPE) and ventilator parts, thereby supporting frontline healthcare workers and patients [27,28,29,30,31,32,33,34,35,36,37].

In terms of shelter and housing, 3D printing offers innovative solutions for constructing temporary and permanent structures in disaster-stricken areas [38]. Temporary shelters can be quickly assembled and customized to meet the specific needs of displaced populations, while permanent housing solutions provide resilient and cost-effective alternatives to traditional construction methods [39,40]. Additionally, the ability to produce replacement parts and custom tools on demand facilitates the swift repair of damaged infrastructure, restoring essential services and reducing downtime [41,42].

Beyond immediate response efforts, 3D printing also plays a pivotal role in community engagement and preparedness. Educational programs can equip residents with the skills to utilize 3D printing technology for emergency preparedness, fostering a culture of resilience [43,44,45,46,47,48,49,50]. Collaborative design initiatives allow communities to work together with local authorities and organizations to create tailored solutions, enhancing cooperation and ownership in disaster management efforts [51,52].

Makerspaces, which serve as collaborative hubs for digital fabrication, significantly promote 3D printing technology within communities [53]. These spaces provide access to both entry-level and advanced 3D printing equipment, enabling individuals and entrepreneurs to familiarize themselves with the technology and apply it in practical ways. By participating in makerspaces, community members gain hands-on experience, contributing to the development and refinement of 3D printing projects [54,55]. This engagement has historically facilitated the proliferation of low-cost 3D printing solutions, empowering local populations to innovate and address unique challenges. Furthermore, makerspaces foster a sense of community and collaboration, encouraging residents to share knowledge and resources [56].

This collective approach enhances the overall resilience of the community, ensuring that members are well prepared and equipped to respond effectively to emergencies. The hands-on involvement and continuous learning opportunities provided by makerspaces are crucial in building a knowledgeable, adaptive, and resilient community, capable of leveraging 3D printing technology to improve disaster preparedness and response [57].

The benefits of 3D printing in disaster management are manifold, encompassing speed, efficiency, cost-effectiveness, customization, and adaptability. The ability to rapidly deploy and produce necessary items on demand is critical in emergency situations where time is of the essence [58]. Moreover, the reduced production and transportation costs associated with local manufacturing contribute to overall cost-savings and logistical ease. The capacity for customization ensures that solutions are fit for purpose, while the flexibility of 3D printing allows for continuous improvement and adaptation as situations evolve [59].

In conclusion, 3D printing represents a transformative advancement in the field of disaster management, particularly within smart cities. Its rapid production capabilities, adaptability, and versatility make it an invaluable tool in enhancing the efficiency and effectiveness of emergency response efforts. As smart cities continue to evolve, the integration of 3D printing technology will undoubtedly play a crucial role in building resilient, responsive, and adaptive disaster management systems [60,61]. This review aims to provide a comprehensive overview of the various applications and benefits of 3D printing in this context, highlighting its potential to transform disaster management practices in smart cities.

Section 2 briefly presents the chosen methodology; Section 3 represents the results; Section 4 provides the discussion; Section 5 presents the main conclusions of the paper.

2. Materials and Methods

To assess the transformative impact of 3D printing on disaster management in smart cities, we utilized a multifaceted research approach, incorporating case study analysis, technology evaluation, and community engagement assessment.

Firstly, our analysis focused on specific case studies where 3D printing technology was employed effectively in disaster management scenarios. These case studies were chosen based on their relevance and demonstrable impact, particularly in the production of medical supplies, construction of emergency shelters, and repair of critical infrastructure. Noteworthy examples include the rapid manufacturing of personal protective equipment (PPE) and ventilator components during the COVID-19 pandemic, as well as the deployment of 3D printing for housing and infrastructure restoration in the aftermath of natural disasters. These cases provided practical insights into the real-world applications and benefits of 3D printing technology during emergencies.

Secondly, we evaluated the various 3D printing technologies and materials used in these disaster management efforts. This involved a detailed review of the technical specifications and performance characteristics of different 3D printing methods such as fused deposition modeling (FDM), stereolithography (SLA), and selective laser sintering (SLS). Additionally, we assessed the suitability of different materials, including plastics, metals, and composites, for producing essential items needed in disaster scenarios. By examining these technologies and materials, we aimed to understand their practicality, efficiency, and adaptability in emergency contexts.

To systematically classify 3D printing methods relevant to disaster management in smart cities, this study categorizes the technology into three principal types: fused deposition modeling (FDM), stereolithography (SLA), and selective laser sintering (SLS). Each method offers unique advantages, making them suitable for distinct applications in disaster response scenarios.

Fused deposition modeling (FDM), the most widespread 3D printing technology, is highly accessible and cost-effective. It uses thermoplastic filaments such as PLA (polylactic acid), ABS (acrylonitrile butadiene styrene), and PETG (polyethylene terephthalate glycol), making it ideal for creating emergency tools, medical supplies, and replacement parts in community-level settings. Its simplicity and low barrier to entry make FDM particularly valuable in local makerspaces and community hubs for fostering resilience during crises.

Stereolithography (SLA), on the other hand, is a resin-based technology that excels in producing highly detailed and precise components. It is widely used in applications requiring fine resolution, such as custom prosthetics, dental tools, and other specialized medical devices. SLA’s ability to create intricate designs with smooth finishes makes it indispensable for high-precision manufacturing during disaster recovery.

Selective laser sintering (SLS) utilizes powdered materials, including polymers and metals, to produce robust and durable parts. SLS is particularly suited for creating complex geometries and high-strength components required in critical infrastructure repairs and emergency shelters. Its ability to utilize high-performance materials enhances its role in large-scale disaster-response operations where strength and reliability are paramount.

To ensure uniformity and reliability across these technologies, the applicable ISO and ASTM standards for 3D printing processes were reviewed and integrated. ISO/ASTM 52900-15 [62] (Additive manufacturing—General principles—Terminology) establishes the foundational definitions and concepts essential for standardizing additive manufacturing practices. Similarly, ISO/ASTM 52910-18 [63] (Additive manufacturing—Design—Requirements, guidelines, and recommendations) provides a comprehensive framework for designing 3D-printed components, ensuring they meet the structural, functional, and safety requirements necessary for emergency applications. Additional relevant standards include ISO 17296-2 [64] (Additive manufacturing—Overview of process categories and feedstock) and ASTM F2921 [65] (Standard terminology for additive manufacturing), which sup-port the classification and evaluation of materials and processes used in disaster contexts.

Furthermore, we explored the role of community engagement and educational programs in leveraging 3D printing technology for disaster preparedness. This included an analysis of initiatives designed to educate and train community members in 3D printing skills, as well as the establishment of makerspaces that serve as hubs for local innovation and collaboration. Makerspaces are particularly significant as they provide access to 3D printing equipment and foster a collaborative environment where residents can develop practical solutions tailored to their communitygs needs. Case studies from various smart cities illustrate how these programs contribute to enhancing disaster readiness and fostering a culture of resilience.

Through synthesizing data from technology evaluation, community engagement initiatives, and case studies, our research aimed to provide a comprehensive understanding of the role of 3D printing in disaster management within smart cities. This integrative approach allowed us to identify key themes and trends, evaluate the effectiveness and limitations of 3D printing technologies, and propose strategies for future development and implementation in urban disaster response systems.

3. Results

3.1. Technology Evaluation

The adoption of 3D printing technologies in disaster management includes a range of different applications, from small-scale desktop printers accessible to individual citizens to large-scale industrial machines capable of constructing shelters and houses. This section provides an overview of the primary 3D printing techniques used in these contexts, highlighting their unique capabilities and contributions to disaster response efforts.

3.1.1. Desktop 3D Printing Technologies

Desktop 3D printers have gained substantial traction in recent years due to their affordability, ease of use, and versatility. These printers are increasingly found in homes, schools, and community makerspaces, enabling individuals to produce a wide array of items on demand. In disaster management, desktop 3D printers serve as vital tools for rapidly addressing urgent needs, particularly in the immediate aftermath of an event when supply chains are disrupted, and access to essential items is limited.

Among the various desktop 3D printing technologies, FDM is the most prevalent. FDM printers create objects by extruding thermoplastic raw materials (filaments) through a heated nozzle, which deposits the material layer by layer according to digital design files. This method is favored for desktop applications because of its cost-effectiveness and the broad range of materials available. Common filaments include the following:

• Polylactic acid (PLA): A biodegradable plastic derived from renewable resources such as corn starch. PLA is easy to print with and produces minimal odor, making it ideal for home use. In disaster scenarios, PLA can be used to print a variety of items, including personal protective equipment (PPE) such as face shields and mask components, as well as educational tools and household items.
• Acrylonitrile butadiene styrene (ABS): Known for its toughness and impact resistance, ABS is often used for more demanding applications. It can produce durable parts that withstand higher temperatures and stresses. During disasters, ABS can be employed to create components for emergency shelters, temporary infrastructure repairs, and robust tools needed for various relief activities.
• Polyethylene terephthalate glyCol (PETG): Combining the ease of printing associated with PLA and the strength of ABS, PETG is a versatile filament suitable for creating strong, resilient parts. In emergency contexts, PETG can be used to produce medical devices, water and food containers, and other critical supplies that require durability and safety. Figure 2 depicts an FDM desktop 3D printer while fabricating a three-dimensional item [66].
• In addition to FDM, resin-based 3D printing technologies like stereolithography (SLA) and digital light processing (DLP) are also popular among desktop users. These printers use light to cure liquid resin into solid objects, resulting in high-resolution prints with fine details. SLA 3D printers use a laser to trace and solidify each layer of a liquid resin. The high precision of SLA makes it suitable for producing intricate parts and prototypes that require fine detail. In disaster management, SLA can be used to create medical models, dental devices, and other specialized components that benefit from high accuracy and smooth finishes.
• Similar to SLA, DLP uses a digital light projector to cure resin. DLP printers are generally faster than SLA, as they cure entire layers at once. This speed advantage is beneficial in disaster situations where rapid production of parts is critical. DLP can be used for similar applications to SLA, including the production of detailed medical devices and custom tools. The ability of desktop 3D printers to quickly produce customized solutions onsite is particularly valuable in disaster scenarios.

Stereolithography (SLA) and selective laser sintering (SLS) are advanced 3D printing technologies that find significant applications in smart cities, particularly in areas requir-ing precision and durability.

SLA, known for its ability to produce high-resolution components with intricate de-tails, is particularly useful in healthcare applications within smart cities. For example, SLA has been employed to fabricate custom prosthetics, dental models, and surgical tools, ena-bling rapid response to medical emergencies. This capability is especially beneficial in disaster scenarios, where localized production of critical medical devices can address supply shortages and ensure timely care for affected populations.

SLS, on the other hand, excels in producing robust and mechanically strong parts suitable for urban infrastructure and industrial applications. For instance, in disaster-prone smart cities, SLS has been used to create replacement parts for water distribution systems and transportation infrastructure, ensuring quick restoration of essential services. The use of materials such as high-strength polymers and metal composites in SLS makes it ideal for producing durable components that can withstand harsh environmental condi-tions, enhancing the resilience of urban systems. These applications demonstrate the versatility of SLA and SLS in addressing the diverse needs of smart cities, from healthcare to critical infrastructure, showcasing their potential to support urban resilience and sustainability.

Table 1. Key applications of desktop 3D printing in disaster scenarios.

Applications	Description
Medical supplies	During health crises or disasters, there is often an urgent need for medical supplies. Desktop 3D printers can produce items such as face shields, mask components, and even parts for ventilators. The rapid prototyping capabilities of these printers ensure that designs can be greatly improved and tailored to specific needs.
Emergency tools and components	Natural disasters frequently damage infrastructure, necessitating quick repairs. Desktop 3D printers can create tools and replacement parts for equipment, helping restore functionality quickly. Items such as wrenches, connectors, and brackets can be printed on demand, reducing downtime and dependency on external supplies.
Customization and adaptability	One of the major strengths of desktop 3D printing is its ability to produce customized solutions tailored to specific needs. Whether it is a custom-fit orthopedic brace or a uniquely designed component for a water filtration system, the adaptability of 3D printing ensures that solutions are precisely suited to the requirements of the situation.

lists some relevant key applications.

By equipping citizens with desktop 3D printers and the skills to use them, communities can become more resilient and self-reliant in the face of disasters. Local production of essential items not only speeds up response times, but also fosters a culture of innovation and preparedness, vital for effective disaster management in smart cities.

3.1.2. Large-Scale 3D Printing Technologies

While desktop 3D printers are invaluable for producing small-scale, customizable items quickly and efficiently, large-scale 3D printing technologies extend the potential of additive manufacturing to the construction of substantial structures and infrastructure. These technologies are particularly transformative in disaster management, where the need for rapid, robust, and cost-effective construction solutions is critical.

Contour crafting is a large-scale 3D printing technology specifically designed for constructing buildings and other large structures. This method employs a computer-controlled robotic arm to extrude layers of concrete or other building materials, creating walls and other structural components layer by layer. The primary advantages of contour crafting in disaster management include speed, cost-efficiency, and the ability to construct complex shapes and designs without the need for extensive manual labor.

Table 2. Key features and benefits of contour crafting technology in disaster management.

Feature	Description
Speed of construction	In disaster-stricken areas, providing immediate shelter is paramount. Contour crafting can significantly reduce construction time compared to traditional methods. A typical house can be constructed in a matter of days rather than weeks or months. This rapid construction capability is crucial in providing quick relief to displaced populations.
Cost-efficiency	Traditional construction methods often involve high labor costs and significant material waste. Contour crafting minimizes these issues by using precise amounts of material and reducing the need for skilled labor. The automation of the building process also ensures consistent quality and reduces the likelihood of human error.
Structural integrity and design flexibility	The layers of material extruded by the robotic arm create strong, stable structures that can withstand harsh environmental conditions. Additionally, the flexibility of the technology allows for the construction of complex designs that can be tailored to specific needs, such as integrating disaster-resistant features or optimizing space for community use.

refers to the key features and potential benefits of contour crafting in disaster management.

Selective laser sintering (SLS) is another large-scale 3D printing technology that has significant applications in disaster management. SLS operates by using a high-powered laser to selectively fuse powdered materials, such as nylon, metals, or ceramics, into solid objects based on digital design files. This technology stands out for its exceptional ability to produce parts with high mechanical strength and durability, making it ideal for the demanding conditions often encountered in disaster zones.

The process begins with a thin layer of powdered material spread across the build platform. The laser then traces the cross-sectional area of the part onto the powder, fusing the particles together to form a solid layer. This layer-by-layer approach continues until the entire part is constructed. The excess powder, not fused by the laser, serves as a support structure for the part during the build, eliminating the need for additional support materials and simplifying post-processing.

Table 3. Key features and benefits of SLS 3D printing technology in disaster management.

Feature	Description
Durability and strength	SLS-produced items are renowned for their robustness and durability. This makes them ideal for constructing parts of emergency shelters, temporary infrastructure, and other critical components that need to withstand severe environmental stressors.
Material versatility	SLS can utilize a wide range of materials, including pol ymers, metals, and composites. This versatility allows for the production of various essential items, from structural components to complex machinery parts, ensuring that the specific needs of disaster management can be met effectively.
Onsite production and flexibility	One of the significant advantages of SLS technology is the ability to produce items onsite, reducing the need for transportation and logistical delays. This is particularly beneficial in remote or inaccessible areas where delivering supplies can be challenging. Onsite production also allows for real-time customization and adjustments based on the evolving needs of the disaster situation.

refers to the key features and potential benefits of the SLS 3D printing technique in disaster management.

3.2. Community Engagement and Educational Programs

Incorporating 3D printing technologies into community engagement and education programs plays a critical role in enhancing disaster preparedness and resilience. These initiatives not only equip residents with the skills to effectively use 3D printing technology, but also foster a culture of innovation and collaboration that is critical to rapid emergency response.

In this regard, education programs concentrating on 3D printing technology would be key to community capacity building. In this case, such programs would mainly target a large set of participants, schoolchildren to adults, and would include both theoretical knowledge and practical skills. Acquiring general knowledge in 3D printing will help community members increase their designing and modifying capacity, selection of proper materials, and operation of 3D printing machines. The integration of 3D printing in school curricula helps nurture a new generation of problemsolvers and innovators. A student learns how to design and fabricate objects, whether it be a simple tool or a complex prototype, using additive techniques in 3D. This will enhance not only their technical skills but also their creativity and team skills. At the level of preparedness for any disaster, students may exercise the technology by developing some projects like the design of emergency shelters or medical supplies. Adults, too, can join in to learn about 3D printing at community centers and local organizations, which often offer various workshops and training events. Such programs bring together as many people from the community as possible, offering them readiness for a disaster. For example, they learn how to make use of 3D printers in the production of life-critical items in case of an emergency, such as a spare part for an essential machine that needs to be fixed, or medical devices, and even a tool crafted specifically for a given purpose. Building this capacity means that when disaster strikes, communities can have swift and effective responses.

Likewise, makerspaces are collaborative environments where community members come together to share resources, tools, and expertise around any area of digital fabrication, such as 3D printing. These are the spaces that foster local innovation and, in the process, local resilience. In essence, makerspaces provide access to very-high-quality 3D printing equipment that most people might not be able to purchase or need for everyday use. They also serve as platforms for knowledge exchange, where novices are mentored by experts, at the same time working on different projects together. By integrating within the makerspaces, community members can develop solutions according to their own standards and needs. This collaborative development makes both the products and tools valuable and effective. For instance, a community can prepare for a natural disaster by designing and printing modular shelter components that will be quickly assembled and disassembled on demand.

In this context, a number of smart cities have successfully implemented programs that leverage 3D printing technology to enhance disaster readiness by promoting community engagement. These case studies provide valuable insights into the effectiveness of such initiatives. Thus, the incorporation of 3D printing into community engagement and educational programs has a profound impact on disaster preparedness and resilience. By empowering residents with the skills and tools to produce necessary items locally, communities become more self-reliant and capable of responding quickly to emergencies. The collaborative and innovative spirit fostered by these programs also enhances overall community cohesion and readiness.

Table 4. Initiatives taken by smart cities regarding leveraging 3D printing technology to enhance disaster readiness by promoting community engagement.

Smart Cities	Description
Barcelona, Spain	Barcelona’s Fab City initiative includes a network of makerspaces that are integral to the city’s disaster preparedness strategy. These spaces are equipped with 3D printers and other digital fabrication tools, enabling the local production of emergency supplies and infrastructure components. During the COVID-19 pandemic, these makerspaces played a crucial role in producing PPE and medical equipment, demonstrating their capacity to respond to urgent needs [67].
Amsterdam, Netherlands	Amsterdam has integrated 3D printing into its educational programs and community projects. The city’s makerspaces host regular workshops and training sessions, teaching residents how to use 3D printing technology for various applications. In disaster scenarios, these skills have proven invaluable, with community members able to produce critical items such as water filtration components and temporary housing structures [68].
New York City, USA	New York City has developed a comprehensive approach to integrating 3D printing into its disaster management plans. Through partnerships with local schools, libraries, and community centers, the city offers extensive training programs and access to 3D printing facilities. This widespread availability and knowledge of 3D printing technology have empowered residents to contribute actively to disaster response efforts, from creating customized medical supplies to repairing damaged infrastructure [69].

lists a number of such relevant case studies.

3.3. Case Studies

In the sector of disaster management, 3D printing has emerged as a revolutionary technology, providing rapid and localized solutions to meet urgent needs. “Field Ready”, a humanitarian organization, has effectively utilized 3D printing in Haiti to address critical gaps in medical supplies and equipment maintenance. Their efforts demonstrate how this technology can enhance healthcare delivery and build resilience in disaster stricken regions [70].

Field Ready’s initiative in Haiti primarily focuses on the production of essential medical supplies and the repair of vital medical equipment. One of their key projects involved the creation of umbilical cord clamps, which are crucial for preventing infections in newborns. These clamps were often in short supply in Haiti, exacerbating the challenges faced by healthcare providers. By leveraging 3D printing technology, Field Ready was able to produce these clamps locally at a significantly reduced cost—approximately USD 0.60 per clamp compared to the traditional USD 1 to USD 3.

This cost efficiency allowed for broader distribution and ensured that more newborns received the necessary care. Additionally, Field Ready has prototyped and distributed over 110 printed items, including a unique prosthetic hand, showcasing the potential for customized medical solutions tailored to individual needs [70].

In addition to producing medical supplies, Field Ready also focuses on repairing critical medical equipment in Haiti. Many hospitals and clinics struggle to maintain and repair essential devices, leading to prolonged downtime and reduced capacity to treat patients. Field Ready addresses this issue by designing and printing replacement parts for broken equipment. For example, they repair baby warmers by producing new corner clips that are more robust and better fitting than the original parts. This intervention is crucial for neonatal care, ensuring that hospitals can provide necessary services to premature and low-birth-weight infants without interruption. By restoring these devices to working order, Field Ready significantly improves the operational efficiency of healthcare facilities in the region [70].

In Kathmandu, following the devastating 2015 earthquake, Field Ready applied 3D printing technology to address critical supply chain disruptions [67]. One significant achievement was the production of spare parts for medical equipment. Hospitals in the affected areas often faced shortages of essential components, rendering crucial devices nonfunctional. Field Ready’s team designed and printed custom parts onsite, such as the replacement components for baby warmers. These new parts were not only durable but also tailored to fit better than the originals, ensuring that neonatal care could continue without delays. This rapid onsite manufacturing capability proved vital in maintaining healthcare services during a period of extreme need [70].

Beyond medical equipment, Field Ready also tackled the problem of water supply in internally displaced persons (IDP) camps. Improvised connections and broken pipes frequently disrupted water distribution, posing severe health risks. Field Ready responded by designing and printing custom pipe fittings directly in the camps. These fittings were used to repair and improve water distribution systems, providing a stable and reliable water supply to 18 households. This intervention not only addressed immediate water needs but also demonstrated the versatility and utility of 3D printing technology in creating practical, durable solutions in disaster stricken environments [70].

Three-dimensional printing played a role in the recovery efforts following the 2011 Japan tsunami, although its application was not as widespread or high-profile as in some other disaster scenarios [71]. The technology was used primarily to produce essential supplies and parts, helping to address shortages and logistical challenges in the aftermath of the disaster [71]. In the aftermath of the tsunami, one of the notable uses of 3D printing was in the production of customized replacement parts for damaged machinery and infrastructure. This was crucial because the disaster caused extensive damage to industrial equipment and transportation systems [72]. For example, 3D printing was employed to create specific parts that were difficult to source quickly through traditional manufacturing, thus speeding up the repair processes and aiding in the recovery of critical infrastructure [72,73].

Moreover, 3D printing facilitated the creation of prototypes and models used in planning and reconstruction. By producing detailed 3D models of affected areas, planners and engineers could better visualize the damage and design effective rebuilding strategies. This application of 3D printing proved valuable in coordinating efforts and ensuring that reconstruction plans were both efficient and resilient to future disasters [73]. While 3D printing did not directly contribute to large-scale housing solutions immediately following the tsunami, mostly due to the radiation contamination, its role in producing necessary parts and aiding in planning underscored its potential utility in disaster recovery scenarios.

In another reported case, 3D printing played a notable role in the aftermath of Hurricane Maria in Puerto Rico, particularly in addressing critical infrastructure and communication challenges [74]. After the hurricane, which decimated 90% of cell towers and left the island with severe communication issues, local entrepreneurs leveraged 3D printing technology to create solutions for connectivity. For instance, a startup named ALQMY developed a prototype called Firestarter using the Gigabot 3D printer. These devices were designed to work on low-band-frequency networks, enabling decentralized communication without relying on the damaged infrastructure. This allowed for basic SMS and GPS communication, crucial for coordinating relief efforts and resource allocation in the immediate aftermath of the disaster [74,75].

Additionally, 3D printing was used to create durable, weather-resistant signage to indicate locations where free Wi-Fi was available. This was vital since the few places with operational Wi-Fi could provide crucial communication links for the community. Foundation for Puerto Rico partnered with re:3D to produce these signs quickly and cost-effectively, demonstrating rapid deployment of 3D printing technology to meet urgent needs in disaster recovery [75,76]. Such initiatives highlight the significant impact of 3D printing in providing immediate, practical solutions during the critical phases of disaster recovery, showcasing its potential for enhancing resilience and preparedness in future emergencies.

As mentioned earlier in this manuscript [30], during the COVID-19 pandemic, 3D printing played a crucial role in addressing shortages of personal protective equipment (PPE) and medical supplies. The flexibility and speed of additive manufacturing allowed for rapid production and adaptation to the evolving needs of the crisis [77,78]. One of the primary applications was the production of PPE, such as face shields and masks [79,80,81,82]. Three-dimenstional printing enabled quick response to the urgent demand for these items when traditional supply chains were disrupted. Designs for these items were shared widely through online repositories and social media, allowing individuals and small businesses with 3D printers to contribute to the production effort. This decentralized approach facilitated the rapid scaling of manufacturing capabilities to meet local demands [83]. Additionally, 3D printing was used to produce parts for medical equipment, such as ventilator components and nasal swabs. The ability to print complex parts on demand was particularly valuable when traditional manufacturing processes could not keep up with the sudden surge in demand. For instance, hospitals and healthcare providers were able to prototype and produce necessary components quickly, which was critical in addressing immediate shortages and ensuring continuity of care [84,85].

Moreover, the pandemic highlighted the importance of data sharing and collaboration within the 3D printing community. Open-source designs and collaborative projects flourished, enabling rapid dissemination of effective solutions. This collaborative spirit was essential in optimizing designs and improving the functionality of 3D-printed items, ensuring they met the required standards for medical use [85]. In this context, 3D printing significantly contributed to the COVID-19 response by providing a flexible and rapid manufacturing solution for critical supplies, fostering community collaboration and enhancing the resilience of supply chains during a global crisis.

Another reported relevant case in the literature concerns the Vulcan II project. This project was undertaken by WinSun Decoration Design Engineering Co., Ltd. (Shangai, China) and stands out as a prominent case study in the field of large-scale 3D printing applications for residential construction [86]. Initiated in 2014, this innovative project represents a significant advancement in construction technology, illustrating the potential of 3D printing to revolutionize the housing industry. The project’s implementation of a giant 3D printer to construct ten single-story homes in China provides a compelling example of how additive manufacturing can address key challenges in building efficiency and cost-effectiveness [86].

The core of the Vulcan II project involved the use of a large-scale 3D printer capable of extruding a special concrete mixture to create entire building components layer by layer [87]. This method allowed each house to be constructed in approximately 24 h, a striking contrast to traditional construction timelines. The technology’s ability to rapidly produce durable and functional housing units highlights its potential to offer swift solutions in scenarios where conventional methods would be impractical. The integration of this technology demonstrates a significant leap in construction efficiency, making it possible to produce habitable structures in a fraction of the time required by traditional methods [88].

The impact of the Vulcan II project extends beyond its speed of construction. The affordability and durability of the 3D-printed homes underline the technology’s promise as a viable solution for addressing housing shortages and providing emergency shelter in disaster-stricken areas. Additionally, the flexibility inherent in 3D printing allows for the customization of design features to meet specific needs, further enhancing the technology’s utility [89]. This adaptability is particularly advantageous in varying environmental conditions and for creating housing solutions tailored to diverse demographic requirements. Thus, the Vulcan II project not only exemplifies the practical application of 3D printing in construction but also highlights its potential to transform housing solutions on a global scale. Figure 3 depicts the 3D printing equipment of the Vulcan II project at work.

In another instance, the Tecla Housing Project, launched in 2016 by the Italian architecture firm Mario Cucinella Architects in collaboration with the World’s Advanced Saving Project (WASP), represents a significant advancement in sustainable housing [90]. This project, which derived its name from a mix of the words technology and clay, embodies an innovative use of 3D printing technology to create an eco-friendly and highly efficient housing solution [91]. By utilizing a 3D printer capable of extruding a biodegradable mixture of local soil and natural fibers, the Tecla project demonstrates how contemporary technology can be harnessed to build structures that align with environmental and sustainability goals [92].

The project’s approach involved constructing a prototype house with the aid of a 3D printer over a period of just a few weeks. The printer utilized an environmentally friendly material that significantly reduces the carbon footprint associated with traditional building methods. The use of local soil and natural fibers not only minimizes environmental impact but also contributes to lowering construction costs [93]. This efficient construction process showcases the practical benefits of integrating 3D printing with sustainable materials, highlighting the technology’s potential to produce durable housing solutions with minimal ecological disruption.

The prospects of the Tecla project extend beyond its immediate construction. By emphasizing the use of locally sourced and biodegradable materials, the project provides a model for addressing housing needs in a manner that is both economically and environmentally beneficial [94]. This approach is particularly valuable in disaster-stricken areas, where access to conventional building materials might be limited, and the environmental impact of construction is a critical concern. The Tecla project thus illustrates how innovative technologies like 3D printing can play a pivotal role in developing sustainable and adaptable housing solutions for diverse global challenges.

Another relevant case discussed in the literature is that of the “Emerging Designs” project, undertaken by DUS Architects in 2018, representing a pioneering effort in the application of 3D printing technology for modular housing in The Netherlands [95]. This initiative sought to explore the potential of 3D printing to revolutionize housing construction by creating modular units that are both rapidly deployable and highly customizable. The project leveraged a large-scale 3D printer capable of fabricating modular components from a variety of materials, including concrete and bioplastics, to construct housing units that could be assembled and disassembled with ease [96].

The construction process for the Emerging Designs project involved the creation of several modular housing units within a relatively short timeframe. These units were specifically designed to be versatile, allowing for rapid assembly and disassembly to meet diverse housing needs [97]. The incorporation of different materials, such as concrete and bioplastics, provided a balance between structural integrity and environmental considerations. This approach underscores the adaptability of 3D printing in producing housing solutions that can be quickly adapted to changing circumstances and requirements [98,99].

The impact of the Emerging Designs project highlights the significant advantages of 3D-printed modular housing in addressing temporary and emergency housing needs. The ability to deploy and reconfigure these units efficiently makes them particularly useful in disaster scenarios where traditional construction methods may be too slow or impractical. Furthermore, the modular design of the units enhances their overall flexibility, allowing for easy relocation and reconfiguration [100]. This capability not only facilitates the provision of immediate shelter but also aligns with broader goals of sustainable and adaptable housing solutions in a smart city concept.

In another relevant case, the ICON project, initiated by the 3D printing company ICON in 2020, represents a significant milestone in the quest for affordable housing solutions through advanced construction technology [101]. Based in Austin, Texas, the project aimed to demonstrate the viability of 3D printing for producing durable and cost-effective homes. Utilizing a proprietary concrete mixture and a large-scale 3D printer, ICON successfully constructed a series of 3D-printed houses, with each unit completed in just a few days. This rapid construction capability underscores the potential of 3D printing to transform traditional building processes [101,102].

The ICON project highlights several key benefits of 3D printing in the housing sector. By dramatically reducing construction time compared to conventional methods, the project addresses critical issues related to housing shortages and affordability. The use of a specialized concrete mixture ensures that the homes are not only economically viable but also resilient and durable [103]. This approach presents a promising alternative for areas facing housing crises, particularly in regions affected by disasters where traditional construction resources and methods are often limited.

In this context, the ICON project serves as a valuable case study in the potential of 3D printing to drive innovation in affordable housing [104]. The ability to produce high-quality homes quickly and at a lower cost opens up new possibilities for addressing long-standing housing challenges. The project’s success exemplifies how emerging technologies can offer sustainable and scalable solutions to pressing global issues, paving the way for more widespread adoption of 3D printing in the construction in dustry. Figure 4 depicts a 3D-printed house as a result of this work using large-scale contour crafting technology [103].

Finally, the “3D Printed Community” project that was launched in 2021 by the nonprofit organization “New Story” in collaboration with “ICON” marks a notable effort in leveraging 3D printing technology to address housing challenges on a significant scale [105,106]. Taking place in Mexico, this initiative aimed to create an entire neighborhood of 3D-printed homes specifically designed to provide affordable and high-quality housing for low-income families. By utilizing a large-sized 3D printer and a proprietary concrete mixture, the project demonstrated the efficiency of 3D printing in fabricating durable homes, with each one of them completed swiftly in a matter of very few days. This rapid construction capability depicts the potential of 3D printing to revolutionize housing development [106].

The project’s focus on Mexico highlights the pressing need for innovative housing solutions in regions facing economic challenges and housing shortages. The choice of Mexico was made as the project reflects a strategic decision to address significant housing needs in a country where low-income households often struggle with marginal living conditions [107]. By building a whole neighborhood of 3D-printed homes, the initiative showcases the practical application of 3D printing technology in creating scalable and cost-effective housing solutions that can be deployed swiftly. The ability to construct a number of homes in a short timeframe provides a compelling alternative to traditional building methods, which are often hindered by longer construction times and elevated costs [108].

The broader impact of the “3D Printed Community” project extends to its potential for global replication in similar contexts. It demonstrates how additive manufacturing can offer scalable and practical housing solutions in disaster-stricken areas worldwide. In Mexico, this approach not only addresses immediate housing needs but also sets a precedent for future developments in affordable housing. The success of the project serves as a model for how advanced technologies can be harnessed to tackle housing crises, offering a sustainable and adaptable solution that could be applied to various regions facing similar challenges.

4. Discussion

The incorporation of 3D printing in the field of smart cities offers notable benefits, especially in terms of rapid manufacturing and extensive customization. One of the main advantages of 3D printing is its ability to quickly and accurately create complex structures. This feature is extremely beneficial in smart cities, since it allows infrastructure to adapt to the ever-changing needs of urban populations. Three-dimensional printing has the capacity to streamline the production of affordable homes, urban furniture, and specialized transportation components. The precision of 3D printing minimizes material waste and accelerates construction schedules, thereby promoting sustainable urban development practices. In addition, the use of 3D printing allows for the creation of regional manufacturing capacities, reducing reliance on complex supply chains, and, thereby, reducing carbon emissions associated with transportation. This aligns with the environmental goals of smart cities, which seek to use sophisticated technologies to reduce their environmental footprint.

Nevertheless, there are several challenges associated with integrating 3D printing into smart cities. One important obstacle is the substantial initial expense involved in acquiring 3D printing equipment and the required resources. While the long-term advantages of decreased waste and enhanced production speed may compensate for these expenses, the initial investment might provide a substantial obstacle, especially for cities in developing areas. Furthermore, the existing technical constraints of 3D printing, such as the size and durability of printed objects, may not yet satisfy the demanding criteria of particular large-scale urban projects. To fully harness the capabilities of 3D printing in urban development, it is imperative to tackle these constraints. Furthermore, there are ongoing worries regarding the environmental repercussions of the materials utilized in 3D printing. Although the technology has the capacity to decrease waste, it is crucial to acknowledge and tackle the environmental issues linked to the production and disposal of specific print materials. This can be accomplished by implementing sustainable practices and recycling programs.

The presence of regulations is an extra obstacle to the widespread implementation of 3D printing in smart cities. The current building rules and regulations may not sufficiently account for the novel methods and materials employed in 3D printing, leading to regulatory uncertainties that could impede the widespread adoption of these emerging technologies. Collaboration between policymakers and industry stakeholders is crucial to update regulations and standards in order to integrate the progress achieved in 3D printing technology. Ensuring safety and reliability in urban areas will necessitate comprehensive testing and validation of novel materials and processes. The absence of well-defined and supportive legislative frameworks will impede the smooth incorporation of 3D printing technology into smart cities, leading to substantial delays and hurdles. Furthermore, it is imperative to establish international cooperation in order to develop universally accepted 3D printing guidelines. This will enable the widespread sharing of advancements and optimal methods to enhance urban development worldwide.

In addition, the successful incorporation of 3D printing into smart cities necessitates a proficient staff capable of operating and maintaining advanced printing devices. Extensive training programs and educational initiatives are necessary to provide personnel with the fundamental skills and abilities. Investing resources in training and workforce development is crucial for tackling the skills gap and optimizing the utilization of 3D printing technologies. Moreover, cultivating a culture of innovation and ongoing education in urban design will enable cities to fully harness the capabilities of 3D printing, resulting in advancements in flexible, efficient, and eco-friendly urban landscapes. Efficient cooperation among academia, business, and government agencies is crucial for creating educational programs and certification systems that can adapt to technological advancements and fulfill the evolving needs of the labor market.

The role of 3D printing in the nexus of catastrophe theory and smart cities is underpinned by its remarkable ability to dynamically respond to the cascading effects of disasters. Catastrophe theory provides a mathematical framework to describe sudden shifts in complex systems, such as urban environments, where seemingly minor disruptions can lead to rapid and unpredictable changes. In the context of disaster management within smart cities, these tipping points often manifest as infrastructure breakdowns, resource shortages, or failures in critical services.

By integrating 3D printing technologies into urban disaster-response strategies, cities can proactively mitigate these cascading effects. The technology enables the on-demand production of essential resources, such as medical supplies, temporary shelters, and replacement components for damaged infrastructure. This capacity not only reduces reliance on traditional supply chains, which are often disrupted during emergencies, but also allows for rapid adaptation to evolving needs in real time. For instance, during the COVID-19 pandemic, 3D printing was pivotal in producing critical medical equipment, such as face shields and ventilator components, demonstrating its versatility and speed in addressing unexpected crises.

The flexibility of 3D printing aligns seamlessly with the principles of resilience embedded in smart city frameworks. Resilience in this context refers to the ability of urban systems to absorb shocks, recover swiftly, and adapt to changing conditions. By enabling localized manufacturing and customization, 3D printing fosters self-reliant communities that can respond effectively to both anticipated and unforeseen challenges.

A systematic application of ISO/ASTM standards further amplifies the potential of 3D printing in disaster management. Standards such as ISO/ASTM 52900-15 and ISO/ASTM 52910-18 ensure uniformity and quality in output, which is critical when deploying life-saving equipment and structural components. These standards also facilitate interoperability, allowing diverse stakeholders—including municipal authorities, humanitarian organizations, and private manufacturers—to collaborate effectively. This interoperability is especially crucial in smart cities, where interconnected systems and multidisciplinary approaches are key to achieving resilience.

Moreover, the adoption of these standards supports scalability and replicability across different urban settings. By adhering to standardized practices, cities can implement proven 3D printing solutions tailored to their specific needs while ensuring compatibility with broader regional or global disaster response efforts. In doing so, 3D printing not only acts as a tool for immediate relief but also becomes an integral part of long-term resilience planning in smart cities, bridging the gap between catastrophe theory and practical urban management.

As 3D printing technology continues to evolve, its future integration into smart cities holds immense potential for reshaping urban environments. One of the most promising areas is the incorporation of advanced materials, such as biodegradable composites and self-healing materials, into the 3D printing process. These materials will not only enhance the sustainability of urban infrastructure but also extend the longevity of critical struc-tures, reducing the need for frequent repairs and replacements. Additionally, 3D printing can enable the creation of decentralized manufacturing hubs within smart cities, allowing for the local production of goods and reducing dependency on global supply chains. These hubs would foster community-driven innovation, empowering local populations to create customized solutions tailored to their specific needs, from medical devices to emer-gency shelter components.

The future of 3D printing in smart cities also lies in its ability to support highly personalized urban solutions. Adaptive furniture, modular housing, and tailormade medi-cal devices will provide citizens with a greater sense of agency and comfort. Furthermore, the integration of 3D printing with the Internet of Things (IoT) and artificial intelligence (AI) will enable smart cities to develop real-time monitoring systems that optimize the manufacturing process. This will be especially beneficial for dynamic urban challenges, such as disaster recovery, infrastructure maintenance, and the efficient use of resources. Finally, 3D printing aligns closely with the principles of a circular economy. By facilitat-ing the recycling of waste materials into new products, it will help cities reduce their environmental footprint and contribute to more sustainable urban ecosystems, making them both resilient and adaptive to future needs.

5. Conclusions

In conclusion, the incorporation of 3D printing technology in smart city initiatives presents a transformative opportunity to enhance urban resilience, sustainability, and adaptability. The ability to rapidly produce customized and complex structures offers significant advantages in addressing the dynamic needs of urban populations, particularly in emergency response and infrastructure development. The precision and efficiency of 3D printing reduce material waste and construction time, aligning with the environmental goals of smart cities by achieving minimization of the produced ecological footprint. However, the adoption of this technology is not without challenges. High initial costs, technical limitations, regulatory uncertainties, and the need for a skilled workforce pose significant barriers that must be addressed to fully realize the potential of 3D printing. Collaborative efforts among policymakers, industry stakeholders, and educational institutions are essential to overcome these challenges, including updating regulatory frameworks, developing sustainable practices, and investing in workforce training. Furthermore, international cooperation to standardize 3D printing practices will facilitate the global sharing of advancements and best practices, benefiting urban development worldwide. As smart cities continue to evolve, the strategic integration of 3D printing technology will play a crucial role in building resilient, efficient, and sustainable urban environments capable of meeting the complex demands of the future.