Actuator Requirements for Robot Hands: Torque Density, Precision, and Compliance

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The article explains that robot hands are among the most demanding actuator applications, since they must simultaneously meet requirements for precision, dexterity, force generation, compactness, safety, efficiency, and reliability. Unlike large industrial robot joints, robot hands must deliver human-like functions within very limited space, making actuator selection a central design decision. Key requirements include high torque density and power density, appropriate speed trade-offs, and precise positioning with low backlash and high-resolution feedback. The text also highlights repeatability, compliance for handling fragile objects and interacting with humans, precise force control, and backdrivability as critical considerations.

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