Two professors at The American University in Cairo (AUC) have developed an innovative construction system using Robotic Additive Manufacturing (AM) that is both sustainable and environmentally friendly. Hanadi Salem, professor and chair of AUC's Department of Mechanical Engineering and the director of the Additive Manufacturing Centennial Lab (AMCL), and Sherif Abdelmohsen, professor and chair of AUC's Department of Architecture and the director of the Robotic Fabrication lab (RFL), have teamed up to develop a sustainable construction system using robotically controlled AM, which uses metal and clay-based materials as the prime material for construction. AM is a state-of-the-art technology that uses metallic wires operable on the construction site using movable robotic arms. The sustainable system developed at AUC's AMCL—the first of its kind locally and in the Middle East—adopts the cutting-edge technology of robotic deposition of construction materials for building complex structures, using reduced energy consumption and almost zero CO2 emissions compared to conventional processes. Salem explained that AM could produce high-value products at minimum waste, high production rates, and reduced cost while adopting customized, innovative structural designs at a lower lead time. "Thus combining both the clay and metal robotic controlled AM in construction engineering reduces carbon emissions coupled with very low energy consumption making it a clean technology suitable for sustaining a cleaner environment." As Salem stated, metal AM reduces energy consumption by 45% and carbon emissions by 95%. Robotic-controlled metal AM technology will have a major contribution to construction and architecture. Towers, bridges, tunnels, complex architectural structures and building facades are currently focused on the AM technology, especially for onsite construction. While clay has always been an important material in construction throughout history, the Red fire clay used at AUC's RFL is harder and more durable. It can withstand higher-temperature and pressure, making it ideal for use in high-performance applications. "The red fire clay is a high-temperature resistant material composed of kaolin, feldspar, and quartz, while normal clay bricks used for mainstream construction in Egypt are made from moulded and baked soil or mud," said Abdelmohsen. The uniquely designed clay bricks produced at AUC's RFL offer new possibilities for the construction industry. Abdelmohsen explained that with robotic 3D printing, custom bricks could be created with unique shapes, sizes, and designs that can be tailored to specific building requirements. "It is much more efficient in producing bricks compared to traditional methods, as it eliminates the need for manual moulding and firing. It also generates less waste, as any unused or scrap material can be easily recycled and reused. It allows for greater control over the production process, resulting in bricks with consistent quality, strength, and durability." Using locally available resources, like clay-based materials instead of traditional bricks that are abundant in Egypt, will help achieve precision and accuracy when adopting the latest technology. Looking at the bigger picture, Abdelmohsen added that using robotically-controlled additive manufacturing in the Egyptian construction industry could potentially make housing and infrastructure more accessible for a broader segment of the population. "Not to mention that it could have various positive impacts, including job creation, improved efficiency, and innovation." Salem also emphasised that aside from the positive impact of AM on the environment, such revolutionary technological advances present opportunities that push the boundaries of societal progress based on small and medium enterprises. "AM, in fact, will integrate with traditional manufacturing to complement it rather than replace it. With AM, there is the freedom to design, inspire innovation and positively impact society in an eco-friendly manner as well as reduce the drain of foreign currency. It will also provide companies with the means to limit outsourcing to third parties by developing concepts in-house and creating an advantage over competitors by shortening the product development cycle." Salem and Abdelmohsen's work was displayed at AUC's pavilion at COP27's Green Zone last November reflecting the University's extensive work in different areas of focus within the climate change and sustainability priorities.
