The essence of rpsexdoll’s light technology is material innovation. The industry-leading nano-porous silica gel has a density as low as 0.6g/cm³ (traditional silica gel 1.15g/cm³), making the weight of a normal 160cm size machine drop from 38kg to 22kg, with a weight reduction rate of 42%. In 2023, TUV Rheinland testing in Germany showed that the material had an A tensile strength of 8.5MPa (industry standard ≥5MPa) at a Shore A hardness of 8±2, and its tear resistance was up to 25kN/m, which is 67% higher than that of traditional TPE materials. Toray of Japan’s carbon fiber reinforced composite (CFRP) skeletal system can not only reduce the internal supporting structure weight to 1.2kg (4.8kg for a steel frame), but also double the bending fatigue life of the joints to 500,000 cycles (ISO 527 test standard).
The key to the breakthrough lies in the technology of foam. The TPU product produced by the supercritical CO₂ foaming process has its cell diameter controlled at 20-50μm and 0.3g/cm³ density, 26% that of ordinary silicone. When filling areas such as the rpsexdoll chest, its own weight is reduced by 74% under identical volume. The case of the 2022 Munich Materials Exhibition is definitive evidence that this material possesses an error of only ±0.8% dimensional stability for the environmental conditions of -20°C to 60°C, against ±3.5% for the native material, while its rebound rate continues to surpass 98% (as demonstrated by ASTM D3574). However, it should be noted that its puncture strength is 40% weaker than that of conventional materials, and the chances of damage increase to 23% when it encounters sharp objects (pencils with hardness ≥3H).
Applications of aerogel composite materials have brought a new era of ultra-light. NASA has achieved an SiO₂ aerogel-silicone composite material with a thermal conductivity of only 0.015W/(m·K) and density of 0.16g/cm³. Applied to rpsexdoll’s skin, 1mm can possess the insulating performance of ordinary 5mm silicone and reduce the power consumption of the heating system to 80W from 300W. The “AirSkin” products of the 2024 CES Innovation Award winner DollTech utilize the application of this material in components of only 0.8kg/m² (2.7kg/m² of standard materials) but at a cost of up to 450/kg (30/kg of standard silicone). In the actual test, this material’s recovery time upon deformation under the pressure of 50N was shortened to 0.3 seconds (1.2 seconds for regular materials), but the wear resistance index was lowered to 6,000 friction cycles (ISO 4649 standard ≥ 10,000 cycles).
Environmentally friendly and light-weight solutions for bio-based materials are coming near. Avantium’s Netherlands-produced PEF (Polyethylene furan diformate) material, which is plant cellulose-based and has a density of 0.9g/cm³, is used. Its application to rpsexdoll spherical plain bearings reduces the friction coefficient from 0.25 to 0.12, reducing the requirement for head rotation torque by 55% (from 1.8N·m to 0.8N·m). The 2023 LCA (Life Cycle Assessment) indicates that the carbon footprint for this material is 2.1kg CO₂/kg (4.7kg CO₂/kg for the petroleum-based plastic), but its creep resistance performance under a 40 ° C /80%RH condition yields a deformation of 1.2mm after 1000 hours loading (acceptable limit ≤0.5mm). The Toyota Bobu developed flax fiber reinforced composite material has a density of 0.45g/cm³. When used in the internal structure of rpsexdoll, it is 63% lighter than aluminum alloy. However, it needs to be compounded with a water-proof coating (50μm thick) in order not to weaken strength when the humidity is above 70% (from 38MPa to 22MPa).