What the Draft Standard Proposes
The source describes a draft standard for humanoid-robot dexterous-hand component reliability, issued for comment by a national quality-inspection center. As reported in the source, the draft would cap oil leakage from the housing: no more than 3 mm of oil-stain diameter per instance on the exterior, and a cumulative oil-stain area of no more than 15 square millimeters after 500 hours of operation. These numbers are draft values from a document referenced by the source; they should be treated as an indication of regulatory direction rather than confirmed requirements.
Why Leakage Is Being Regulated
The rationale is practical. Grease that bleeds out of a joint stains the housing, and once it reaches fabric surfaces it is expensive to clean because fabrics adsorb lubricating oils readily. In a home or office setting, oil leakage is not a functional failure, but it is a visible, hard-to-repair quality defect that drives complaints and returns. Regulating the visible symptom forces manufacturers to control the underlying cause: excessive free oil in the grease.
The Technical Red Line: Oil Separation
For home use, the source states that an oil separation rate above 10% at 100°C for 24 hours essentially disqualifies a grease. Evaporation loss is also tightly controlled, because in enclosed living spaces the volatile components of the grease contribute to indoor air quality concerns. A grease that bleeds or evaporates cannot meet the draft’s stain limits, no matter how well it performs on load capacity. Oil separation and evaporation are therefore the two parameters a grease developer should control first.
Cold Start and Noise Clauses
Two more draft-related requirements matter for grease selection. First, a -20°C cold-storage test: if the grease hardens at low temperature, the joint stalls on cold mornings, so low-temperature flow must be verified. Second, a noise limit of 45 dB or below during high-precision manipulation: noise is treated as part of component reliability, which ties back to film stability and damping in the meshing contact. Cold-start performance is also a user-experience issue: a joint that stalls at -20°C will be reported as a defect even if the grease meets every bench specification at room temperature, so low-temperature flow testing belongs in the same qualification batch as the stain checks.
Validation / Selection Conclusion
Select grease for home-oriented dexterous hands by testing oil separation, evaporation loss, low-temperature flow at -20°C, and noise under high-precision manipulation. Treat the draft limits (3 mm stain diameter, 15 mm2 cumulative area after 500 hours, 45 dB) as design targets. The qualification path is simple: a grease whose oil separation stays below 10% and whose evaporation loss is minimal will almost automatically satisfy the stain and odor expectations, leaving cold-start and noise as the remaining validation gates.
