Robotics
Backdrivability
ActivePublished
Key
innovation
A measure of actuator reversibility that governs compliance, contact safety and force sensing.
Category
Robotics
Abstraction level
Primitive
Operation level
Robot control
How it works
Backdrivability depends on gear ratio (lower = better), friction, rotor inertia and mechanism efficiency. Direct-drive and quasi-direct-drive (QDD) actuators are inherently backdrivable; for others, force feedback (torque sensors) or elastic elements (SEA) are used to achieve effective compliance.
Problem solved
Robots that contact humans and unpredictable environments need compliance and force sensing; stiff, non-backdrivable drives are unsafe and tolerate impacts poorly.