The robotics field is changing the way people think, build, interact, and most importantly perceive robots. Robots have long been perceived as machines made of metals that their sole purpose is to perform repetitive tasks in isolated environments. However, with advancements in hardware, software, and manufacturing technologies robots are becoming smarter, interactive, and safer. This enables them to safely operate alongside us during our daily activities.

Robots are versatile machines that can take on multiple forms and perform numerous tasks on demand. This is why robotics can be defined as the science and engineering of systems that use sensing for intelligent action.

Examples of robots include humanoid robots such as Tesla Optimus, Boston Dynamics Atlas, pib robot (an intelligent open-source 3D printable robot), and Sophia. These robots can perform complex dynamic behaviors like walking, jumping, and handling objects while recognizing and synthesizing speech, making them artificially intelligent and interactive. Additional examples of robots include bioinspired robots that take inspiration from natural organisms and animals to mimic their functions and behavior, assistive and biomedical robots that can aid in the rehabilitation process of patients or augment the performance of a user, self-driving and mobile robots that can navigate different environments autonomously, and robotic arms with different end-effectors that perform various tasks such pick and place, sorting, welding, drilling, and many other useful tasks.

The manufacturing of robots has always depended on assembling metal and plastic components, along with power, actuation, and sensing units. The robot’s frame or structure is typically composed of metal or plastic parts that were created using traditional manufacturing processes like computer numerical control (CNC) machining. This process, also known as subtractive manufacturing, involves multiple operations being performed on a raw piece of metallic or plastic material to produce the final product. One of the primary drawbacks of this particular manufacturing process is its limited capacity to produce complex shapes and structures. Additionally, the weight of the manufactured components cannot always be significantly reduced without compromising their strength, which is another disadvantage. Manufacturing robots and their components with lightweight structures and complex geometries is highly desired.

Fortunately, it is possible to create complex soft, rigid, and hybrid robotic structures, actuators, and sensors with various mechanical properties using additive manufacturing. Additive manufacturing, also known as 3D printing, is the process of creating a component by stacking thin layers of material on top of each other. The thickness of each layer can vary from 1 to 300 micrometers based on the 3D printing technology.

There are several 3D printing technologies that are advancing robotics, including fused deposition modeling (FDM), stereolithography (SLA), digital light processing (DLP), selective laser sintering (SLS), and material jetting.

Fused Deposition Modeling (FDM) is the most commonly used technology among 3D printing technologies for printing soft, rigid, and hybrid plastic components. This is because FDM 3D printers are affordable for hobbyists, scientists, and engineers, and are open-source, which makes them easily modifiable to meet specific requirements. In addition, the plastic materials that can be 3D printed using such technologies can have different properties when it comes to their stiffness in terms of stretchability and softness. In addition, FDM 3D printers can 3D print reinforced materials with the ability to print multiple materials simultaneously. FDM 3D printers are a cost-effective option for 3D printing; however, they do have certain limitations. They cannot print metal components and highly complex plastic structures and lack the extremely high printing resolution of SLA and DLP technologies.

Through metal 3D printing complex low-weight shapes with high strength can be achieved which is impossible with conventional manufacturing techniques. Similarly, when it comes to 3D printing extremely soft materials, silicone 3D printing outperforms the softest plastics that can be 3D printed with other technologies.

The use of various 3D printing technologies has enabled the rapid fabrication of soft, rigid, and hybrid sensors, actuators, and robotic structures for diverse applications with desired performance specifications. Moreover, in some cases, it is currently possible to fully 3D print robotic structures that do not require any assembling processes.

The adoption of 3D printing technology has not only facilitated rapid progress in the field of robotics, but it has also opened up the field to the community through various open-source robotics projects. These projects can be leveraged for learning about robotics, contributing to the research field of robotics, and developing impactful robotic systems that can have a transformative impact on our communities.

Examples of impactful open-source robotic projects include the pip humanoid robot, InMoov humanoid robot, Poppy humanoid robot, Open Bionics robotic prosthetic hand, and Open Dynamic Robot Initiative (ODRI) robot dog.

The future of 3D printing is bright and it will have a significant impact on all fields, particularly those that use robotics. It is difficult to imagine robots not being integrated into many fields in the near future, as they are becoming increasingly intelligent, safer, more adaptable, and capable of holding meaningful conversations and responding to our requests.