3D Printing: The Core Driver Behind Humanoid Robots' Lifelike Movements

2025-11-20 14:06:47

Recently, the launch of Xpeng's humanoid robot IRON has sparked widespread discussion in China's embodied intelligence sector. Its highly human-like gait has not only won acclaim but also raised doubts. Due to its overly human-like gait, coupled with the discovery of human ear contours on it and protrusions on its back that resembled women's undergarments, many people questioned: "There is a real human model hidden inside IRON."

Subsequently, He Xiaopeng, the CEO of Xpeng, released a video to address the doubts. He used scissors to cut open the fabric on IRON's legs and had the robot walk around. Then he unzipped the zipper on its back, revealing the robot's body, which is milky white and features a dense grid structure.

Figure 1. He Xiaopeng unzipping IRON

Yet public curiosity still lingers: why, unlike most robots that move with stiffness and jitteriness, can Xpeng's robot walk with such smooth, human-like fluidity?

Behind this technological breakthrough lies the support of 3D printing technology, which has become a transformative force in the manufacturing of advanced materials for robots—especially elastomers that simulate human muscles. As one of the biggest suppliers in the elastomer material field, Juntai Textile & Polypollmer Technology is capable of producing various high-performance materials, including elastomers, through 3D printing technology. Its printing speed is 20 to 100 times faster than that of traditional processes. In the robotics sector, its clients include Zhiyuan Robotics, Ubtech, and others.

By leveraging 3D printing technology, Juntai Textile & Polypollmer Technology has developed a new type of elastomer that features flexible responsiveness and lightweight properties. If the coexistence of humans and robots becomes an inevitable reality in the future, then in addition to having an intelligent "brain," whether humanoid robots possess a body as coordinated, safe, and efficient as human muscles will equally determine whether they can truly integrate into daily life.

3D Printing: Revolutionizing Elastomer Production for Robots

Elastomers, a material between rigid substances and silicone, offer unique flexibility and durability. They can be twisted, squeezed, and dropped without damage, making them ideal for replicating human muscle functions in robots. Unlike traditional rigid materials like stainless steel and aluminum that result in stiff movements, elastomers enable smooth, coordinated motion by responding flexibly to mechanical demands.

3D printing addresses the key challenge of producing elastomers with precise lattice structures. Conventional manufacturing relies on molds, which fail to control internal structural details accurately. In contrast, 3D printing uses photosensitive resin that solidifies under light, weaving intricate elastomer components layer by layer—mirroring the natural formation of human muscles. This process not only achieves high precision but also boosts production speed by 20 to 100 times compared to traditional methods, as demonstrated by companies like Juntai Textile & Polypollmer Technology, a supplier for leading robot firms such as Zhiyuan Robotics and Ubtech.

Figure 2. Elastomeric materials with a lattice structure

Advantages of 3D-Printed Elastomers in Humanoid Robots

Lightweight Design: Elastomers printed via 3D technology are 60-70% lighter than traditional rigid materials of the same volume. This reduces the robot's overall weight, easing the burden on motors, cutting energy consumption, and minimizing safety risks when interacting with humans.

Enhanced Breathability: The lattice structure of 3D-printed elastomers improves heat dissipation, a critical feature for robots that operate continuously for long periods.

Biomimetic Performance: These elastomers act like muscle groups, enabling robots to replicate human-like stretching and traction. This biomimicry is essential for robots to enter daily scenarios such as households and elderly care.

GIF. Xpeng’s robot is walking on the stage

3D Printing's Role in Xpeng's Ecosystem and Industry Trends

Xpeng's focus on biomimicry in IRON highlights 3D printing's strategic value. The robot leverages 3D-printed elastomers for its lifelike gait, complementing other biomimetic technologies like bionic hands and vision systems. This biomimetic design is key to Xpeng's closed-loop ecosystem linking automobiles and robots.

3D-printed elastomers are already adopted by major players—Ubtech's Walker S2 uses them in elbows, Zhiyuan's Lingxi X2 in arms and chest plates, and Figure 02 in joint shock-absorbing muscles. As the robotics industry moves toward human-robot coexistence, 3D printing will continue to drive innovation in materials and manufacturing. It not only enables the production of complex, high-performance components but also supports the scalability of humanoid robots, paving the way for the $20 trillion market that Xpeng forecasts for the next 10-20 years.