Robot and control method of optimizing robot motion performance thereof

• US 20110106303A1
• Filed: 10/25/2010
• Published: 05/05/2011
• Est. Priority Date: 10/30/2009
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Myung Hee, Roh, Kyung Shik, Lim, Bok Man, Lim, San
• Granted Patent: US 9,037,292 B2
• Time in Patent Office: Days
• US Class Current: 700/245
• CPC Class Codes: B62D 57/032 with alternately or sequentially lifted supporting base and legs; with alternately or sequentially lifted feet or skid B62D57/024 takes precedence

Abstract

A robot and a method of controlling the same are disclosed. The robot derives a maximum dynamic performance capability using a specification of an actuator of the robot. The control method includes forming a first bell-shaped velocity profile in response to a start time and an end time of a motion of the robot, calculating a value of an objective function having a limited condition according to the bell-shaped velocity profile, and driving a joint in response to a second bell-shaped velocity profile that minimizes the objective function having the limited condition.

Claims

1. A method of controlling a robot, the method comprising:

forming a first bell-shaped velocity profile in response to a start time and an end time of a motion of the robot;

calculating a value of an objective function having a limited condition according to the first bell-shaped velocity profile; and

driving a joint of the robot in response to a second bell-shaped velocity profile that minimizes the objective function having the limited condition.

2. The method according to claim 1, wherein the forming of the first bell-shaped velocity profile in response to the start time and the end time of the motion includes:

forming a trajectory of either a joint needed for motion of the robot or a center of gravity of the robot.

3. The method according to claim 2, wherein the trajectory includes information of a joint angle, a joint velocity, and a joint acceleration needed to perform the motion.

4. The method according to claim 1, wherein the objective function having the limited condition recognizes a value (J_min) using the following Equation:

5. The method according to claim 1, wherein the bell-shaped velocity profiles represent a variation of velocity with time of a robot profile.

6. The method according to claim 1, wherein the forming of the first bell-shaped velocity profile in response to the start time and the end time of the motion includes:

forming a plurality of initial bell-shaped velocity profiles in response to a certain start time and a certain end time of the motion.

7. The method according to claim 6, wherein the calculating of the value of the objective function having the limited condition according to the first bell-shaped velocity profile includes:

repeatedly calculating the value of the objective function having the limited condition in response to the initial bell-shaped velocity profiles.

8. The method according to claim 1, wherein the second bell-shaped velocity profile is determined by determining a start time and an end time at which the objective function having the limited condition is minimized.

9. The method according to claim 8, wherein a trajectory is formed by the start time and the end time at which the objective function having the limited condition is minimized, and the trajectory is determined to be the second bell-shaped velocity profile.

10. A robot, comprising:

an input unit to receive a motion command of a robot; and

a controller to form a first bell-shaped velocity profile in response to a start time and an end time of a motion of the robot and to calculate a value of an objective function having a limited condition according to the first bell-shaped velocity profile; and

a driver to drive a joint of the robot in response to a specific second bell-shaped velocity profile that minimizes the objective function having the limited condition.

11. The robot according to claim 10, wherein the controller forms a trajectory of either a joint needed for motion of the robot or a center of gravity of the robot.

12. The robot according to claim 10, wherein the controller recognizes a value (J_min) of the objective function having the limited condition using the following Equation:

13. The robot according to claim 10, wherein the controller forms a plurality of initial bell-shaped velocity profiles in response to a certain start time and a certain end time of the motion.

14. The robot according to claim 13, wherein the controller calculates the value of the objective function having the limited condition according to the initial bell-shaped velocity profiles, and drives a joint in response to a specific second bell-shaped velocity profile that minimizes the value of the objective function.

15. The robot according to claim 13, wherein the controller drives each joint or the center of gravity needed for the motion in response to the second bell-shaped velocity profile that minimizes the value of the objective function.

16. The robot according to claim 10, wherein the controller arbitrarily determines the start time and the end time of the motion, and forms an initial bell-shaped profile of either a joint needed for the motion or a center of gravity of the robot.

17. The robot according to claim 10, wherein controller determines the second bell-shaped velocity profile by determining a start time and an end time at which the objective function having the limited condition is minimized.

18. The robot according to claim 17, wherein a trajectory is formed by the start time and the end time at which the objective function having the limited condition is minimized, and the trajectory is determined to be the second bell-shaped velocity profile.

19. The robot according to claim 10, wherein the controller includes a command interpreter to interpret the received motion command, and a command generator connected to the command interpreter to generate a motion command.