## Book Chapter: Chapter 11

Robot Control

#### Chapter 11 Autoplay

Autoplay of the YouTube playlist for all videos in this chapter.  This description box will not be updated with information about each video as the videos advance.

#### 11.1. Control System Overview

This video introduces different robot control objectives (motion control, force control, hybrid motion-force control, and impedance control) and typical block diagram models of controlled robots.

#### 11.2.1. Error Response

This video introduces the error response for a controlled system and characterizes the error response in terms of its steady-state error and its transient response (overshoot and settling time).

#### 11.2.2. Linear Error Dynamics

This video introduces linear error response, where the error dynamics are represented by a linear ordinary differential equation, which can also be represented as a set of coupled first-order differential equations, xdot = Ax. Stability of the error dynamics is achieved if the real components of the eigenvalues of A are all negative, or, equivalently,

#### 11.2.2.1. First-Order Error Dynamics

This video studies error dynamics modeled as a first-order linear ordinary differential equation.

#### 11.2.2.2. Second-Order Error Dynamics

This video studies error dynamics modeled as a second-order linear ordinary differential equation. Stable error dynamics are characterized as overdamped, critically damped, or underdamped.

#### 11.3. Motion Control with Velocity Inputs (Part 1 of 3)

This video introduces proportional (P) control of the position of a single-degree-of-freedom system where the control input is a velocity.

#### 11.3. Motion Control with Velocity Inputs (Part 2 of 3)

This video introduces proportional-integral (PI) control of the position of a single-degree-of-freedom system, and feedforward plus PI feedback control, for the case where the desired position is a ramp as a function of time (constant velocity) and the control input is the velocity. The approach generalizes easily to the control of a multi-degree-of-freedom robot.

#### 11.3. Motion Control with Velocity Inputs (Part 3 of 3)

This video addresses task-space motion control of a robot, where the control inputs are the joint velocities and the desired motion of the end-effector is expressed as its configuration X in SE(3) and the end-effector velocity is expressed as a twist. The proposed control method is a feedforward plus PI feedback controller.

#### 11.4. Motion Control with Torque or Force Inputs (Part 1 of 3)

This video introduces proportional-integral-derivative (PID) control for a single robot joint, as well as PD control to a desired constant position, for the case where the control input is a joint torque or force.

#### 11.4. Motion Control with Torque or Force Inputs (Part 2 of 3)

This video compares PD vs. PID control for setpoint control of a single robot joint moving in gravity, where the control input is a torque.

#### 11.4. Motion Control with Torque or Force Inputs (Part 3 of 3)

This video introduces the computed-torque motion control method for robots, where the control inputs are torques or forces. The controller is defined both in joint space as well as task space.

#### 11.5. Force Control

This video describes Jacobian-transpose-based force control for a robot, both with and without end-effector force-torque feedback.

#### 11.6. Hybrid Motion-Force Control

This video introduces hybrid motion-force control: controlling a robot to generate desired motions in unconstrained directions and desired forces in constrained directions.