1. Introduction to RoboticsKinematics CSCI 4830/7000 September 13, 2010 NikolausCorrell

2. Last week’s exercise Suspension stability

3. Last week’s exercise Statically vs. dynamically stable gaits

4. Last week’s exercise Dynamically stable motions

5. Last week’s exercise Sinuoidalmotions for gait generation

6. Today Forward kinematic Inverse kinematics Feedback position control Mobility Steerability

7. Kinematics Intro How does a robot move? Reference frames

8. Forward Kinematics Given Wheel speeds Wheel radius Axle length Required Speed in robot coords Speed in world coords

9. Inverse Kinematics Given Desired speed in world coordinates Required Set-speed in robot coordinates Wheel-speed

10. Wheel kinematic constraints Wheel HAS to roll Wheel cannot slide

11. Robot kinematic constraints Only standard wheels impose constraints Fixed Steerable Castor, Swedish and Spherical wheels do not

12. Maneuverability Robot moves along x, y and theta Degree of mobility: number of parameters the robot can change just with its wheels Degree of steerability: how many independently steered wheels? Maneuverability = mobility + steerability = Degrees of freedom a robot can manipulate

13. Maneuverability

14. Examples

15. Motion Control Open-Loop vs. Closed Loop

16. Motion Control Calculate forward and rotational speed from position error Easier: express error in polar coordinates

17. Example

18. Homework Reading Chapter 4: up to including 4.1.7 Exercise Program a way-point following robot