Embodiment

A robot's physical body: its specific combination of form, joints, sensors, and actuators.

“Embodiment” (本体) is the term China's embodied-AI industry uses for a robot's physical “body”: its specific hardware form — single-arm, dual-arm, quadruped, or humanoid — how many degrees of freedom it has (roughly, how many joints move independently), which cameras and force sensors it carries, and whether its end effector is a gripper or a dexterous hand. Embodiment determines what a policy can see (its observation space) and what it can output (its action space); the same model usually can't be dropped onto a different embodiment without changes, a mismatch called the embodiment gap. The Open X-Embodiment dataset pools data from 22 embodiments specifically to study cross-embodiment transfer. In industry usage, an “embodiment vendor” (本体厂商) is a company that builds robot hardware, as distinct from a “brain company” that builds only the software models.

ExampleA Franka arm and a Unitree G1 humanoid are two very different embodiments: the former is 7 joints plus a two-finger gripper, while the latter needs to coordinate more than twenty joints across its legs, waist, and both arms at once.

Also called

Robot Embodiment, Robot Body

Related

Cross-Embodiment · Embodiment Gap · Embodiment-agnostic · Degrees of Freedom (DoF) · Humanoid Robot · Robot Body Maker

Sources

Open X-Embodiment: Robotic Learning Datasets and RT-X Models（项目页） (Chinese)
Open X-Embodiment 论文（arXiv 2310.08864） (Chinese)