Lihan Lian

Lihan Lian

Robotics enthusiast. Passionate about optimal control and deep learning.

Taxonomy of Robotic Manipulation: Inverse Kinematics (IK), Operational Space Control (OSC), Impedance Control, Riemannian Motion Policy (RMP) and Geometric Fabrics

less than 1 minute read

Published:

Inverse Kinematics (IK) converts a desired end-effector pose into joint angles and is fundamental for basic motion planning. Operational Space Control (OSC) layers dynamics on top of IK, commanding Cartesian forces/velocities so the robot can track trajectories while rejecting disturbances. Impedance Control then shapes the robot’s apparent mass-spring-damper behavior, enabling compliant contact and human-robot interaction. Riemannian Motion Policy (RMP) generalizes impedance ideas across multiple task maps, blending goal-reaching, joint limits, and obstacle avoidance on curved manifolds. Finally, Geometric Fabrics build on RMP to sculpt global energy landscapes, yielding provably safe navigation around complex environments. This post aims to provide brief explanation for each concepts.

Diifusion Models

DDPM

  • Results

DDIM

  • Results

References

  1. Operational Space Control & Impedance Control
  2. Riemannian Motion Policies & Geometric Fabrics
  3. mjctrl & RMP2

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