What's the Secret to Lighter, More Durable Robots?

As Tesla's Optimus, Figure 01, Walker s1, and other products accelerate their commercial deployment, the global humanoid robotics industry is poised to seize historic new opportunities. The next decade will witness explosive growth in the robotics sector, drawing fierce competition among global tech giants vying for market dominance.

Amid the pursuit of lightweight design, “replacing steel with plastics” has emerged as a hot topic in humanoid robot manufacturing. Next, we will briefly introduce the lightweight materials used in humanoid robots.

vHow to Achieve Light-weighting in Humanoid Robots?

To achieve human-like motion capabilities, humanoid robots must minimize their weight. Excessive weight significantly increases motor load, compromising motion agility, payload capacity, and endurance performance. Currently, common lightweight materials used in humanoid robots include aluminum alloys, magnesium alloys, engineering plastics, and carbon fiber composites.

Ø Aluminum alloy has a density of 2.63–2.85 g/cm³, only 1/3 that of steel, yet possesses high strength. Its specific strength approaches that of high-alloy steel, while its specific stiffness exceeds steel. It offers excellent casting properties, plastic working properties, electrical/thermal conductivity, corrosion resistance, and weldability, making it the preferred lightweight material for humanoid robots.

Ø Magnesium alloy is the lightest metallic structural material, with a density around 1.8 g/cm³, approximately 2/3 that of aluminum and 1/4 that of iron. It boasts a high specific strength of 133, a large elastic modulus, and excellent vibration damping, noise reduction, electromagnetic shielding, and heat dissipation properties. In humanoid robots, magnesium alloys can be used in core components such as skeletal structures, joint modules, and shell assemblies. Compared to traditional materials, they help reduce component weight, enhance drive response efficiency, and improve thermal management and electromagnetic shielding performance. Magnesium alloys are also the key material for weight reduction in Tesla's Optimus Gen2 humanoid robot!

Ø Engineering plastics offer outstanding comprehensive properties: high rigidity, low creep, superior mechanical strength, excellent heat resistance, good electrical insulation, and strong chemical resistance. They can replace metals as structural materials in engineering applications. Common engineering plastics used in humanoid robots include PEEK, PA, PPS, PC/ABS alloys, LCP, and UHMW-PE, etc..

>>PEEK

PEEK offers comprehensive performance characteristics, with rigidity surpassing most specialty engineering plastics. It demonstrates outstanding resilience, heat resistance, wear resistance, and corrosion resistance, while its specific strength far exceeds that of conventional metals. In humanoid robots, PEEK is primarily used for components such as skeletal structures and joint transmission mechanisms. This application reduces component wear, lowers energy consumption and noise levels, enhances the torque-to-weight ratio of robotic joints, enables more efficient and precise movement, and extends the operational lifespan of the robot.

>>PA

Nylon is the most widely used variety among the five major engineering plastics. It features low density, high mechanical strength, rigidity, hardness, and toughness, along with excellent aging resistance and mechanical vibration damping capabilities. It also offers good sliding properties, outstanding wear resistance, machinability, and dimensional stability. PA is utilized in robotics for gears, bearings, and structural components.

>>PC/ABS alloys

PC/ABS alloys combine the excellent heat resistance, weather resistance, dimensional stability, and impact resistance of PC resin with the superior processing flow properties of ABS resin. They are suitable for thin-walled and complex-shaped products, maintaining outstanding performance and formability, and can be used to manufacture humanoid robot shells.

>>PPS

PPS can replace traditional metal components through injection molding and 3D printing technologies, significantly enhancing the lightweight and high-temperature resistance of core components such as joint modules. This provides technical assurance for robots operating under long-cycle, high-load conditions. It can also be used in robot skeletons and connectors to achieve overall body weight reduction.

vHow does OMNISTAB additive enhance the durability and service life of key polymer materials in robots?

In addition to requiring lightweight materials with high strength and durability, humanoid robots impose stricter demands on high-temperature resistance and VOC control. OMNISTAB Antioxidants and HALS can significantly enhance thermal stability during material processing and long-term weather resistance, preventing yellowing and fading of interior components while maintaining aesthetic appeal and mechanical performance stability.

OMNISTAB SOLUTIONS FOR ROBOTS

OMNISTAB AO-80

OMNISTAB AN1790

OMNISTAB HP-136

OMNOSTAB AN3052

OMNISTAB AN9228

OMNISTAB LS119

OMNISTAB LS2020