Three-dimensional (3D) printing is an additive manufacturing method in modified engineering that enables the construction or creation of intricate structures that are otherwise challenging to realize through conventional means. It has contributed immensely to various manufacturing application areas, including electronics, aeronautics, the food industry, and robotics. Four-dimensional (4D) printing, on the other hand, is an evolving field in additive manufacturing having the ability to program objects into various shapes or forms in response to multiple stimuli such as light, water, or heat. The emerging distinguishing factor between 3D and 4D is the added intelligent design, or the ability of materials to form time-reliant deformations in response to stimuli.
Additive manufacturing (AM) is usually termed 3D printing, and it presents a transformative method in the engineering industry that allows for the fabrication of more robust, lighter parts. It utilizes data CAD (computer-aided-design) Software or three-dimensional scanners to instruct the hardware to place material layer-by-layer in exact shapes geometrically. Put as adding material to form an object. Therefore, this paper seeks to address the 3D, 4D printing, additive manufacturing technologies, their benefits, disadvantages, and impacts on project performance. Further, the paper explores the possible undesirable effects these technologies have on health, privacy, and security with additional case illustrations.
Literature Review
Three-dimensional technology has transformed for more than 30 years. Although its emergence as a topic has received a lot of attention recently, the technology has its origin in 1984 by Charles Hull. He developed stereolithography (STA) as the first 3D system (Muehlenfeld, & Roberts, 2018). Henceforth, 3D technology began to transform the manufacturing industry rapidly from 2000 to date. Ever since there have been emerging extensive applications and new markets for 3D systems or printers. For quite some time, patent ownership by some companies such as Stratasys Inc. prevented more advanced techniques. According to Choi et al. (2015), such patents’ expiration has seen an emergence of 3D systems with users able to customize and build 3D printers on their own and alternatively utilize the increasingly available economical three-dimensional printers.
There is increased availability of 3D websites and Software of 3D design such as Thingiverse and Shapeway. These designs are helpful in any project activity. For instance, such designs allow the sharing of user-customizable free 3D digital model designs, resulting in increased access to three-dimensional printers and further spread of the technology of 3D printing. Many countries acknowledged the technology as an innovative fabrication in manufacturing, thereby resulting in the manufacturing industry’s global trend (Choi et al., 2015). 3D printing presents an effective technology in material and energy areas compared to conventional manufacturing systems like drilling, casting, and machining. Additionally, the 3D technology offers reduced wastage utilizing over 80 percent of materials and leads to energy saving by up to 50 percent. The printing of 3D objects is accomplished by layered deposition, a technique also referred to as additive manufacturing (AM). Thus, the 3D approach differs from the principle of creation in subtractive manufacturing, which forms a 3D object by removing material from a solid block (Deshmukh et al., 2020). These capabilities simplify project management by improving the efficiency of underlying tasks.
This process involves carving of material by sawing, broaching, milling, or drilling. 3D printing is commonly referred to as rapid prototyping. Nonetheless, the prototyping incorporates both subtractive and additive manufacturing. Such a combination of these technologies occurs typically based on factors such as cost, selected material for printing, the complexity of the material’s structural geometry, and structural quantity. According to Deshmukh et al. (2020), the distinguishing factor between additive and subtractive fabrication models is the complexity of an object’s geometrical structure. The intricate designs comprised of hollow and solid parts can undergo fabrication through additive manufacturing because of concurrent printing of solid and hollow portions of objects after deposition of layers. The fabrication techniques have their benefits and drawbacks, and as such, the subtractive process is convenient, cost-friendly, and produces several objects within short duration intervals. Some of the additive manufacturing (AM) technologies utilized for 4D printing are categorized differently, considering ink deposition or mode of materials. These are extrusion-centered modes such as direct ink writing (DIW), inkjet, and fusion deposition modeling (FDM). Other methods like vat photopolymerization comprise digital light processing (DLP) and stereolithography (SLA).
Research findings show that 3D printing is underutilized, and its potential is not fully utilized. The technology receives limelight because of the creation of objects to form or transform into various other shapes. This evolution of objects’ shapes forms the basis of four-dimensional (4D) printing technology. Tibbits (2013) was the first to introduce the 4D printing concept through illustration by immersing a 3D-printed structural rod in the water, which subsequently changed into a 3D predesigned geometry. Tibbits disclosed these prospects at the February MIT Conference in his speech in 2013. From then, stimulus mechanisms, 3D printers, relative materials, applications, and design innovation rules have been studied and explored widely (Shie et al., 2019). Thus, 4D-printed structure designs require completely detailed preprogramming by considering any projected time-reliant object deformations. The ability of 3D-printed structures to self-assemble in response stimuli such as chemical reaction, water, pressure, or heat, forms the primary aim of 4D printing (Tibbits, 2014). As such, 4D printing incorporates alteration or change aspects in printed shape over time, relying on ecological stimuli. The 4D and 3D printing processes are almost similar with printing commencing in modeling programs of 3D technology like computer-aided design (CAD) and then followed by design printing using the 3D printer (Zafar & Zhao, 2019).
As aforementioned smart design and materials form the significant distinction between 3D and 4D printing since objects printed in 4D printing possibly alter their function or shape. In constructing 3D objects, specific materials, including ceramics, metals, and plastic, are broad utilized as printing constituents. Nonetheless, these materials are primarily inapplicable to 4D printing due to inadequate response to environmental stimuli. According to Choi et al. (2015), 3D printings of materials have functional properties by modifying procedural parameters like nozzle features, environment for printing, and temperature. Thus, the appropriate selection of materials for 4D printing is essential. Such materials self-assemble when exposed to stimuli and considered smart. The intelligent materials include shape memory polymers (SMP), hydrogels, liquid crystal elastomers (LCE), and shape memory ceramics (SMC) (Jeong et al., 2020). These structures react appropriately to different stimuli. SMP materials are possibly used as filamentous material in the material extrusion (ME) process of printing artificial objects, which refold following their unfolded state by subjecting it to temperature change (Ryan, Down & Banks, 2020).
Additionally, biomaterials form another class of smart materials used in 4D technology. The functional elements that degrade autonomously in vivo have undergone continuous research from the 90s. For instance, Gladman et al. (2016) introduced the biomimetic hydrogen composite printed in a 4D bilayer structure. It could change its shape when underwater because of localized anisotropy swelling. Since the human body comprises a dynamic and continuous system in motion, every part receives exposure to unique environmental conditions. It reacts to changes in body states such as body fluid or temperature with time (Shie et al., 2019). These biomaterials in 4D printing are advantageous and promising in the medical industry. Body parts from printing ought to have dynamic, practical features for utilization inside the body. Over time, there should be degradation of biocompatible materials within the body conditions. Some self-degrading materials include poly-caprolactone (PLC) and polylactic acid (PLA). Study shows that these materials degrade after some years when the polymer chain undergoes total dissolution in the body (Choi et al., 2015).
Examples of these Technologies
3D printing has become inexpensive to purchase, and experts worldwide anticipate that it will soon become typical households. Companies involved in manufacturing are taking advantage of the powerful possibilities these machines provide. As such, each day presents an opportunity for development from aircraft parts to shoes to medical devices. 3D printing has a significant effect on the medical industry. It has supported prosthetic leg production for long-distance athletes, a human heart model, and the creation of alligator tails for alligators with bitten tails. A team experimented in a School of Medicine in Northwestern University Feinberg, Chicago, where a 3D printer ovaries of a mouse birthed healthy pups successfully. In the food industry, plastic 3D printers print chocolate from a digital design created using 3D Software. Moreover, additive manufacturing presents cutting-edge possibilities in the music industries in the production of banjos, flutes, and violins. Live concerts have also incorporated the use of all 3D-printed instruments.
The building of objects layer upon layer presents freedom of design hence reducing wastes. Products from additive manufacturing shoe companies have also incorporated these technologies in printing footwear. For instance, the Adidas Company partnered with AM company called Carbon in 2017 to produce a product known as Futurecraft 4D using the printing technology of Digital Light Synthesis (DLS) (Yang, & Luo, 2019). This forms one adoption scenario in light of the possibilities of 4D technologies. At first, Adidas was using 3D printing technology in its production; nonetheless, in 2018, the company made its partnership with Carbon official, left 3D printing, and brought AM technology to the industry of sports.
In the management of spare parts, there is usually the storing of manufactured parts, after which they are delivered in the warranty period, or scrapping off can happen eventually. Nonetheless, with the advent of additive manufacturing, such parts can be manufactured according to the demand, and this can happen locally without utilizing tools while reaching the precise quantity required. This exact quantity manufacturing happens void of minimum purchase volume, hence evading needless overproduction, thereby ensuring maximum client satisfaction. Therefore, the use of CAD data for the production of spare parts in additive manufacturing helps managers circumvent the resource-intensive logistics in the warehouse. In this case, the spare parts’ data is saved and sent when the need arises, encouraging a decentralized and efficient process.
Faster production of spare parts translates to increased machine uptime and reduced disruptions. To illustrate, Moog Company, an American Manufacturing company in collaboration with Air New Zealand and Microsoft in the aerospace industry, carried out incorporating additive manufacturing. Boeing 777-300 plane headed for the US from Auckland experienced a technical hitch and had a part of the cabin broken. On attaining cruising altitude, the aircrew informed Auckland’s management of urgent replacement of the part to avoid further damage. The management immediately informed the maintenance team, which accessed the digital catalog of Air New Zealand parts, to order a component replacement. The engineering crew identified a possible area in Los Angeles where the part could be 3D printed and shipped straight to the airport. Moog reports that they would have incurred a loss of about $30,000 and an additional 44 days lead-time in utilizing the traditional form.
Additionally, 4D printing enables the manufacture of clothing that adjusts and adapts to the body’s movement and shape. Thus, the United States military tests for color-shifting uniforms depending on environmental conditions or uniforms that control and regulate perspiration considering the environment’s temperature and a soldier’s pulse. Also, 4D printing is applied to the manufacture of shoes used in skiing. A company known as Materialise collaborated with TAILORED FITS in the co-creation of customized ski boots y digitally scanning clients’ feet in-store and afterward designing them for 3D and 4D printing, hence they can react to the different skiing environments and maintaining a warm temperature of the feet. The venture into these boots was to provide a balance of high performance and comfort for skiers.
Opportunities for Technologies in Project Management
The future for project management presents different opportunities given these technologies. Some areas have not been fully explored and still offer room for investigations. For instance, researchers can explore significantly efficient methods for applying environmental stimuli, such as advancing the heat application procedure in thermo-responsive shape memory polymers. Besides, opportunities exist for project management focusing on investigating the methodologies for regulating hydrogels’ moisture absorption. Improving on such structures can create improved actuation precision.
Adoption of 3D printing, 4D printing, and additive manufacturing in project management would revolutionize this field. These technologies are replete with modern manufacturing techniques for quick adaptation to market demands and lessening production. In the current business environment where sustainability is a serious consideration in any boardroom meeting, additive manufacturing has proven a dependable future production approach. According to Vieira and Romero-Torres (2016), 3D printers leverage e-manufacturing canons, which warrants integrating physical object computer models. As such, the enterprise business model must change, influencing support and core activities. Additive manufacturing alters project management operations. For instance, the incorporation of additive manufacturing in the aerospace industry improves project performance for managers. Nonetheless, this statement holds only for project managers who do not fancy an alternative paradigm in the aerospace industry. Other industries which additive manufacturing transform include consumer products, transportation, energy, and the medical field. The essence of 3D and 4D printing is unique to all industrial settings.
The Possible Negative Impact of these Technologies on Health, Privacy, and Security
These technologies have many benefits in the healthcare industry; for instance, 3D ultrasound helps recognize structural hereditary anomalies present in the fetus within a scheduled 17 to 21-week scan. Diagnosis can be made in identifying face flaws of the fetus, such as cleft lip. However, there are also several negative impacts of these technologies on health. Such may include the high utilization of more than usual ultrasound energy levels, which may cause severe side effects to the fetus. Operations of these technologies may demand long training; however, this problem has seen transformations with the advent of customizable and user-friendly Software.
3D printers operate by melting base materials like metals or nanoparticles or plastic filaments, where the smelted materials are stacked layer-wise to form a designed structure. Upon heating these base materials, they dislodge volatile composites into the air around the printer and the formed structure. These by-products discharged into the atmosphere during printing are likely to accumulate over time. Due to their tiny nature, they can result in severe damage once they infiltrate the respiratory system. A study conducted by Environmental Protection Agency (EPA) on examining a 3D filament extruder emission established that filaments discharged vapors and small particles in comparable amounts in other studies. Additionally, a simulation model conducted projected a high mass of particle depositions per lung surface area in nine-year-olds and below.
In terms of privacy and security, 3D printing presents the possibility for invasive actions compared to the internet. The printed products may contain tracking devices installed in the physical areas and not only the computer files. Thus, each 3D printed material can be tracked and is usually a means of collecting consumers’ data to create an opportunity to gather information concerning product usage to decrease production costs and product items in harmony with customers’ needs. However, this tracking poses a threat to people’s privacy. With the 4D technology, where devices that self-print and are installed in the body may at one point develop the ability to collect and reveal the user’s actions (Griffin & Jones, 2020). The RAND paper on additive manufacturing investigates the possibility of 3D printers impacting individual, national, and universal security (Johnston, Smith, and Irwinp, 2018). It anticipates future dangers. This same technology that may at one point make heart valves will as well create gun ports. An experiment involving drones’ programming using a 3D printer demonstrated how easy hackers could use malicious codes in causing actual havoc to the world using a 3D printer. Even though industrial printers have advanced and improved security defenses compared to ordinary home computers, hackers still find their way into highly secure and sensitive grid systems such as the White House and Pentagon.
References
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