Equation 6 · Part 1 · How Embodied AI Actually Works

Symbol tau_ff

\tau_{ff}

\tau_{ff}

What this part means

a feedforward term — gravity compensation, or a reaction-force term handed down from a higher-level controller — added on top.

Its job in the formula

ta $u_f$ f is a part of this expression. Its role is fixed by the surrounding article and by the operations shown in the formula.

Full expressionSymbol tau_ffArticle meaning

Where the article explains it

Here $q_d$ and q are the desired and measured joint positions, $K_p$ and $K_d$ set how stiff and how damped that virtual spring-and-damper is, and $\tau_{ff}$ is a feedforward term — gravity compensation, or a reaction-force term handed down from a higher-level controller — added on top.

The passage around this formula

Here $q_d$ and q are the desired and measured joint positions, $K_p$ and $K_d$ set how stiff and how damped that virtual spring-and-damper is, and $\tau_{ff}$ is a feedforward term — gravity compensation, or a reaction-force term handed down from a higher-level controller — added on top. The learned policy’s contribution to this equation is $q_d$ : a target, updated at whatever rate the policy runs. Everything else in the equation runs at a much…

Read this part in the article →

Learn the underlying idea

A subscript is a label attached below a symbol. It often selects a time step, component, category, or member of a sequence.

Open the illustrated subscripts: which member of a family? guide →

See this notation across published equations →

Sources cited in the article section

[12] Safe Physical Human-Robot Interaction through Variable Impedance Control based on ISO/TS 15066 ↗

These citations provide research context; check each source for the exact claim it supports.