Topic 5: Embodied Action — Manipulation & Environment Interaction

Topic 5 connects high-level autonomy to precise physical interaction with the environment: grasping, placing, delivering objects, and interacting safely with humans.

5.1 Grasping and Precision Control

Effective manipulation requires:

• Inverse kinematics (IK):
  • Compute joint angles for a desired end-effector pose.
  • Respect joint limits and humanoid kinematics from earlier chapters.
• Grip-force regulation:
  • Apply enough force to hold objects securely.
  • Avoid crushing or slipping.
• Slippage detection & correction:
  • Use force/torque or tactile feedback.
  • Adjust grip or re-grasp when needed.

In the autonomy stack:

• High-level tasks specify what to grasp and where.
• Manipulation skills and controllers implement how to achieve a stable grasp.

5.2 Object Placement & Delivery

Placing and delivering objects involves:

• Approach vector alignment:
  • Choose a safe and stable approach direction.
  • Avoid collisions with surrounding surfaces or humans.
• Gentle release:
  • Lower object to surface.
  • Gradually reduce grip force.
  • Ensure object stability before fully releasing.
• Coordinate-based positioning:
  • Represent target positions in map or robot frames.
  • Account for calibration between perception, robot base, and manipulators.

These steps are encapsulated as skills in the library (Topic 3) and invoked by task graphs.

5.3 Human Interaction Tasks

Humanoid robots often interact directly with people. Example tasks:

• Item handover:
  • Approach human.
  • Present object at comfortable height and distance.
  • Wait for confirmation or contact before release.
• Escort person to target room:
  • Navigate while monitoring human position.
  • Maintain safe, comfortable following distance.
  • Communicate progress (e.g., voice or display).
• Cooperative carrying:
  • Share load with human.
  • Use compliant control to adapt to human motion.

Safety and comfort are paramount:

• Use conservative speed and force limits.
• Design behaviors that are predictable and legible to humans.

By the end of Topic 5, you should see how:

• High-level plans are realized through precise, feedback-driven physical interaction.
• Manipulation and human interaction complete the loop from language and goals → perception → planning → control → embodied action.