By VNOVO Technical Support Team
In recent years, the approach of choosing planetary reducers for shoulder joints has been gaining mom
Humanoid robots are moving from factories into homes. On May 20, the ‘PickLight S1’ released by Jiajia Vision provided a signal—it can autonomously complete housework such as folding clothes, doing laundry, cooking, and organizing desktops, planning actions independently based on an embodied intelligence model, and began real-world testing at the Optics Valley Talent Apartment on May 31.
This timing is noteworthy: dexterous hands here face不再是 standardized industrial parts, but non-standardized household objects—sofas, fabrics, porcelain, and users’ zero-tolerance for ‘dirtiness.’
Prior to this, Figure Helix 02 demonstrated dual-robot cooperative bed-making, with the dexterous hand’s real-time perception and manipulation capability for non-rigid objects (fabrics) reaching gram-level accuracy and tactile perception as low as 3 grams. This means that when handling fabrics, the dexterous hand requires continuous, minute, and precise force control—and any grease anomaly will be completely exposed under this high-precision sensing system.
From factory to home: the invisible threshold for grease
Industrial grease formulations focus on service life, tooth fracture resistance, and load-bearing capacity. Oil-bleeding rate, evaporation loss, and noise level ‘meet the minimum standard’ in factory environments. But in home scenarios, the top three user complaints during the first month are often not ‘it’s broken,’ but rather ‘it’s leaking oil,’ ‘there’s a smell,’ and ‘it’s making a creaking noise.’
This is not a selection error—it is an invisible threshold created by the scenario shift.
During fine operations such as folding clothes and wiping tables, dexterous hands make frequent micro-movements—potentially thousands of times per hour. If the grease has a high oil-bleeding rate, base oil will seep out from between the fingers, leaving oil stains on clothes and tables; greases with high evaporation loss release chemical odors in enclosed living rooms, particularly sensitive in kitchen and bedroom environments; greases with poor shear stability rapidly lose consistency under high-frequency micro-movements, causing tooth surfaces to run dry and emit ‘squeaking’ sounds. Even more tricky is the temperature variation in home environments—
These issues are rarely deeply discussed in industrial scenarios but become critical in home scenario selection.
Five core indicators for dexterous hand grease in home scenarios
① Oil-bleeding rate (no oil)
Recommended <10% (100 °C/24 h). Greases with high oil-bleeding rates will exude base oil under high-frequency dexterous hand micro-movements, soiling home environments and causing user complaints about ‘oil stains on robot fingers.’ This indicator is almost never among the top selection criteria in industrial scenarios, but directly affects user trust in home scenarios.
② Evaporation loss (no odor)
Recommended <1.0% (99 °C/22 h, GB/T7325). Greases with high evaporation loss continuously volatilize organic components in enclosed living rooms and bedrooms, generating chemical odors. Not a core selection parameter in industrial scenarios, but directly affects users’ physical comfort in home scenarios.
③ Shear stability (no noise)
Greases containing PTFE thickening agents maintain consistency under high-frequency micro-movements, avoiding abnormal noise caused by tooth surface dry friction. Poor shear stability is the primary cause of high-frequency micro-movement noise in home scenarios.
④ Temperature range
Recommended -50 to 220 °C, covering extreme temperature differentials from winter cold storage to summer kitchens, ensuring grease performance does not degrade across a wide temperature range.
⑤ Starting torque (battery life)
Low starting torque reduces motor energy consumption and extends battery life. Home robots require long standby times and intermittent use—this indicator directly affects user experience.
An engineering reference
Few greases can satisfy all of the above combined indicators. Taking the VNOVO X500 dexterous hand joint grease as an example, its fluorinated oil + PTFE system achieves oil-bleeding rate <10%, evaporation loss <1.0% (99 °C/22 h), operating temperature -50 to 220 °C, and EP load 800 kg—balancing ‘no oil, no odor, no noise’ with long-life lubrication needs in home scenarios.
A final question
When testing home service robot dexterous hands, have you encountered user complaints about oil leaks, odors, or abnormal noise? Where do oil-bleeding rate and evaporation loss rank on your selection checklist? Feel free to share actual test data and work together to fill this ‘invisible threshold.’
