Robot and method for controlling motor speed of the robot

• US 6,528,963 B1
• Filed: 05/30/2001
• Issued: 03/04/2003
• Est. Priority Date: 12/13/2000
• Status: Expired due to Fees

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Hong, Yong-joon
• Primary Examiner(s): Masih, Karen
• Application Number:
  US09/866,771
• Time in Patent Office: 643 Days
• Field of Search: 318/568.13, 318/569, 318/568.11, 318/568.18, 318/568.24, 901/14, 901/20, 901/9, 901/10
• US Class Current: 318/568.18
• CPC Class Codes: B25J 9/1664 characterised by motion, path, trajectory planning
• CPC Class Codes: G05B 2219/33263 Conversion, transformation of coordinates, cartesian or polar
• CPC Class Codes: G05B 2219/40454 Max velocity, acceleration limit for workpiece and arm jerk rate as constraints
• CPC Class Codes: G05B 2219/40549 Acceleration of end effector
• CPC Class Codes: G05B 2219/42175 Velocity, speed points, profile and corresponding acceleration, delta v

Abstract

Disclosed is a method of controlling a robot including a motor having a rotation shaft, an arm part having one end connected to the rotation shaft and interlocking with a rotation of the motor, a position controller controlling the motor, and a main controller generating a speed command profile for controlling the motor, based on the inputted motion command of the arm part and transmitting the profile to the position controller, comprising a step of generating the speed command profile controlling a speed of the motor so as to allow the arm part to have an acceleration profile in uniform speed. With this configuration, the slipping of a workpiece can be prevented and further increasing the motion speed while the arm part is traveling, by making the motion speed of the arm part constant.

Claims

1. A method of controlling a robot including a motor having a rotation shaft, an arm part having one end connected to the rotation shaft and interlocking with a rotation of the motor, a position controller controlling the motor, and a main controller, comprising:

generating a speed command profile to control a speed of the motor based on a motion command of the arm part inputted by a user, and transmitting the profile to the position controller, so as to allow the arm part to have an acceleration profile in uniform speed.

2. The method according to claim 1, wherein the arm part comprises a drive arm having one end connected to the rotation shaft of the motor and the other end provided with a drive shaft thereon, and an interlock arm interlocked with a motion of the drive arm, and

the generating the speed command profile further comprises preparing for a motion control which converts a change angle formed by the drive arm and the interlock arm into a value at rectangular coordinate system, using Equation (1),

3. The method according to claim 2, wherein the motion control preparation further comprises obtaining a traveling distance (Δ

P) of the arm part by a difference (P₁−

P₀) between the value at the initial rectangular coordinate system and the value at the rectangular coordinate system according to the target angle of the arm part.

4. The method according to claim 3, wherein the motion control preparation further comprises establishing a motion speed of the arm part by the user when the traveling distance of the arm part is obtained, and obtaining a motion time of the arm part based on the established motion speed and the traveling distance of the arm part.

5. The method according to claim 4, wherein the change angle of the arm part is obtained according to Equation (3), where P₀ is less than {square root over (2)}*L if the motion time is obtained,

6. A robot including a motor having a rotation shaft, an arm part having one end connected to the rotation shaft and interlocking with a rotation of the motor, and a position controller controlling the motor, comprising:

a main controller to generate a speed command profile to control a speed of the motor based on a motion command of the arm part inputted by a user, and transmitting the profile to the position controller, so as to allow the arm part to have an acceleration profile in uniform speed.

7. A robot comprising:

a motor having a rotation shaft;

an arm part having one end connected to the rotation shaft and interlocking with a rotation of the motor;

a position controller to control the motor; and

a main controller to generate a speed command profile to control a speed of the motor based on a motion command of the arm part inputted by a user, and transmitting the profile to the position controller, thereby allowing the arm part to have an acceleration