By surface treatment technology and material development, the texture of rpsexdoll can approach the real touch of the human body. The use of super-soft silicone (Shore hardness 00-10) instead of traditional TPE (Shore hardness 20) increases the softness of the touch by 60%, but the tear resistance needs to be reduced from 25 MPa to 8 MPa, and it will have a 12% increase in the maintenance rate. A Japanese firm conducted an experiment in 2023, where by adding 30% of silicone plasticizer, the rebound rate of the skin of rpsexdoll at 40°C fell to 0.2 seconds from 0.5 seconds, close to human skin (0.15 seconds), but the cost of the material increased by 45% (the cost of one piece rose from 1,200 US dollars to 1,740 US dollars).
Replication technology for surface texture at a micron level is a significant advance. Nano-imprinting technology (with a precision of ±2 microns) was employed to create dermal patterns (at a density of 200-500 patterns per square centimeter) on the rpsexdoll skin, and the tactile simulation score achieved 4.6/5 points (3.2 points for the conventional process). Data from one particular German laboratory show that the geometry of a 0.1-millimeter-deep sweat pore structure reduces the surface friction coefficient from 0.35 to 0.18, which is near that of human forearm skin (0.15), but the mold development cycle is raised by 30% (from 6 weeks to 8 weeks), and the initial capital is over 50,000 US dollars.
Dynamic soft changes are made possible through the use of temperature-sensitive materials. rpsexdoll impregnated with shape memory alloy (transition temperature 32°C) can increase the local skin temperature by 5-8°C when in contact with the human body, reduce the hardness from Shore 15 to 8, and decrease the elastic modulus by 40%. In 2024, a real test on a North American brand showed that the satisfaction of the touch sense in the chest and abdomen area with this technology increased by 73%, power consumption increased by 25% (the capacity of the battery should be expanded from 6000 mAh to 7500 mAh), and battery life decreased by 20%.
Chemical coating technology achieves optimal long-term retention of touch. After the spraying of a 5% graphene (50 nanometers thick) protective coating of silicone oil, the friction coefficient fluctuation range of rpsexdoll skin was reduced from ±0.12 to ±0.03 in 1000 cleaning cycles test, and the touch consistency felt was enhanced by 80%. A sample of a specific Chinese maker shows that this technology reduces the complaint rate of the touch sense of the product during three years from 18% to 3%, but the price of one spray coating has increased by 28 US dollars (accounting for 9% of the entire material expense).
Bionic technology in biology provides new ways. One South Korean group has developed a cell-level bionic structure (20-50 micrometer pore diameters) which can maintain rpsexdoll skin moist to a level of 15%-18% (which is in the range of the 12%-20% of real human skin), reducing dryness and cracking by 90%. Experimental observations show that when mixed with moisturizing gel (500 cP viscosity) for weekly care, the rate of aging of the material is reduced by 60% (the lifespan is extended from 3 years to 5 years), but the cost of annual care by the users increases by 120 US dollars.
Improvements in environmental flexibility reduce tactile oscillations. The rpsexdoll, with which a humidity sensor (accuracy ± 3%RH) and an automated humidifying equipment (atomizing capacity 5 mL/h) are incorporated, can control the epidermal hardness change rate from ±8% to ±1.5% in a state of dry environment (humidity <30%), and the stability of touch is improved by 4 times. User trials carried out in Dubai in 2023 showed that this solution reduced the rate of negative touch reviews under poor weather from 34% to 6%, but overall weight of the kit increased by 2.3 kg (from 28 kg to 30.3 kg) and transport cost was up by 18%. Through the synergy of multi-disciplinary technologies, the life-like haptic sensation of rpsexdoll is crossing the boundaries between bioengineering and material science.