# US 2014/0156074 A1 · Robot and friction compensation method therefor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0156074 A1 - Document ID: US20140156074A1 - Status: Published application - Kind: A1 - Application number: 14/089,727 - Filed: 2013-11-25 - Published: 2014-06-05 - Earliest claimed: 2012-11-23 - Assignees: Samsung Electronics Co., Ltd. - Applicants: Samsung Electronics Co., Ltd. - Inventors: Kee Hong Seo; Young Do Kwon; Kyung Shik Roh - Web page: https://patentgrep.com/patent/US20140156074A1 ## CPC - B25J 9/1689: {Teleoperation} - B25J 3/04: involving servo mechanisms (servo-actuated heads B25J15/02) - G05B 2219/39181: Compensation of coulomb friction in joint - B25J: MANIPULATORS; CHAMBERS PROVIDED WITH MANIPULATION DEVICES ({manipulators specially adapted for use in surgery A61B34/70; manipulators used in cleaning hollow articles B08B9/04}; manipulators associated with rolling mills B21B39/20; manipulators associated with forging machines B21J13/10; {manipulators associated with picking-up and placing mechanisms B23P19/007}; means for holding wheels or parts thereof B60B30/00; {vehicles with ground-engaging propulsion means, e.g. walking members B62D57/02, B62D57/032; devices for picking-up and depositing articles or materials between conveyors B65G47/90, B65G47/91; manipulators with gripping or holding means for transferring packages B65H67/065}; cranes B66C; {manipulators used in the protection or supervision of pipe-line installations F17D5/00; walking equipment adapted for nuclear steam-generators F22B37/006}; manipulators specially adapted for, or associated with, nuclear reactors G21C; {apparatus used for handling wafers during manufacture or treatment of semiconductor H10P72/50}) - G05B: CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS (systems for controlling or regulating non-electric variables G05D; systems for regulating electric or magnetic variables G05F; control devices or systems insofar as characterised by mechanical features only G05G) ## Abstract A robot includes a master device including an input unit, the input unit including a first end effector and a first joint, a slave device configured to be controlled by the master device and including a robot arm, the robot arm including a second end effector, a second joint, and a motor configured to drive the second joint, and a controller configured to calculate a friction compensation value to compensate for friction of the second joint based on a speed of the input unit in response to the input unit being in motion, generate a control signal based on the friction compensation value, and transmit the control signal to the motor configured to drive the second joint. ## Claims ### Claim 1 A robot comprising: a master device comprising an input unit, the input unit comprising a first end effector and a first joint; a slave device configured to be controlled by the master device and comprising a robot arm, the robot arm comprising a second end effector, a second joint, and a motor configured to drive the second joint; and a controller configured to: calculate a friction compensation value to compensate for friction of the second joint based on a speed of the input unit in response to the input unit being in motion; generate a control signal based on the friction compensation value; and transmit the control signal to the motor configured to drive the second joint. ### Claim 2 (depends on 1) The robot of claim 1, wherein the controller is further configured to: calculate the friction compensation value based on a speed of the input unit and a kinetic friction of the second joint in response to the robot arm being in motion; and calculate the friction compensation value based on the speed of the input unit, a maximum stationary friction of the second joint, and a motion direction of the input unit in response to the robot arm being stationary, a sign of the friction compensation value being determined based on the motion direction of the input unit. ### Claim 3 (depends on 1) The robot of claim 1, wherein the master device further comprises a speed detector configured to detect the speed of the input unit. ### Claim 4 (depends on 1) The robot of claim 1, wherein the master device further comprises a position detector configured to detect a position of the input unit; and the controller is further configured to calculate the speed of the input unit based on the position of the input unit. ### Claim 5 (depends on 1) The robot of claim 1, wherein the controller is further configured to calculate the friction compensation value by: transforming the speed of the input unit into a speed of the second joint; and multiplying the speed of the second joint by a friction coefficient of the second joint to obtain the friction compensation value. ### Claim 6 A robot comprising: a master device comprising an input unit, the input unit comprising a first end effector, a first joint, and a motor configured to drive the first joint; a slave device configured to be controlled by the master device and comprising a robot arm, the robot arm comprising a second end effector and a second joint; and a controller configured to: calculate a friction compensation value to compensate for friction of the first joint based on a speed of the robot arm in response to the robot arm being in motion; generate a control signal based on the friction compensation value; and transmit the control signal to the motor configured to drive the first joint. ### Claim 7 (depends on 6) The robot of claim 6, wherein the controller is further configured to: calculate the friction compensation value based on a speed of the robot arm and a kinetic friction of the first joint in response to the input unit being in motion; and calculate the friction compensation value based on the speed of the robot arm, a maximum stationary friction of the first joint, and a motion direction of the robot arm in response to the input unit being stationary, a sign of the friction compensation value being determined based on the motion direction of the robot arm. ### Claim 8 (depends on 6) The robot of claim 6, wherein the controller is further configured to calculate the friction compensation value by: transforming the speed of the robot arm into a speed of the first joint; and multiplying the speed of the first joint by a friction coefficient of the first joint. ### Claim 9 (depends on 6) The robot of claim 6, wherein the slave device further comprises a speed detector configured to detect the speed of the robot arm. ### Claim 10 (depends on 6) The robot of claim 6, wherein the slave device further comprises a position detector configured to detect a position of the robot arm; and the controller is further configured to calculate the speed of the robot arm based on the position of the robot arm. ### Claim 11 A robot comprising: a master device comprising an input unit, the input unit comprising a first end effector, a first joint, and a first motor configured to drive the first joint; a slave device configured to be controlled by the master device and comprising a robot arm, the robot arm comprising a second end effector, a second joint, and a second motor configured to drive the second joint; a first controller configured to: calculate a first friction compensation value to compensate for friction of the second joint based on a speed of the input unit in response to the input unit being in motion; generate a first control signal based on the first friction compensation value; and transmit the first control signal to the second motor configured to drive the second joint; and a second controller configured to: calculate a second friction compensation value to compensate for friction of the first joint based on a speed of the robot arm in response to the robot arm being in motion; generate a second control signal based on the second friction compensation value; and transmit the second control signal to the first motor configured to drive the first joint. ### Claim 12 (depends on 11) The robot of claim 11, wherein the first controller is further configured to: calculate the first friction compensation value based on a speed of the input unit and a kinetic friction of the second joint in response to the robot arm being in motion; and calculate the first friction compensation value based on the speed of the input unit, a maximum stationary friction of the second joint, and a motion direction of the input unit in response to the robot arm being stationary, a sign of the first friction compensation value being determined based on the motion direction of the input unit. ### Claim 13 (depends on 11) The robot of claim 11, wherein the first controller is further configured to calculate the first friction compensation value by: transforming the speed of the input unit into a speed of the second joint; and multiplying the speed of the second joint by a friction coefficient of the second joint to obtain the first friction compensation value. ### Claim 14 (depends on 11) The robot of claim 11, wherein the second controller is further configured to: calculate the second friction compensation value based on a speed of the robot arm and a kinetic friction of the first joint in response to the input unit being in motion; and calculate the second friction compensation value based on the speed of the robot arm, a maximum stationary friction of the first joint, and a motion direction of the robot arm in response to the input unit being stationary, a sign of the second friction compensation value being determined based on the motion direction of the robot arm. ### Claim 15 (depends on 11) The robot of claim 11, wherein the second controller is further configured to calculate the second friction compensation value by: transforming the speed of the robot arm into a speed of the first joint; and multiplying the speed of the second joint by a friction coefficient of the first joint to obtain the second friction compensation value. ### Claim 16 (depends on 11) The robot of claim 11, wherein the first controller is provided at the master device or the slave device; and the second controller is provided at the master device or the slave device. ### Claim 17 A robot comprising: a first device comprising an input unit; a second device configured to be controlled by the first device in response to manipulation of the input unit by a user and comprising a robot arm; and a controller configured to: generate a control signal to control movement of the robot arm and compensate for friction of the robot arm based on a speed of the input unit; and transmit the control signal to the robot arm. ### Claim 18 (depends on 17) The robot of claim 17, wherein the controller is further configured to: generate a friction compensation value to compensate for the friction of the robot arm based on the speed of the input unit in response to the robot arm being in motion, and based on a maximum stationary friction of the robot arm in response to the robot arm being stationary; and generate the control signal based on the friction compensation value. ### Claim 19 (depends on 17) The robot of claim 17, further comprising another controller configured to: generate another control signal to control movement of the input unit and compensate for friction of the input unit based on a speed of the robot arm; and transmit the other control signal to the input unit. ### Claim 20 (depends on 19) The robot of claim 19, wherein the other controller is further configured to: generate a friction compensation value to compensate for the friction of the input unit based on the speed of the robot arm in response to the input unit being in motion, and based on a maximum stationary friction of the input unit in response to the input unit being stationary; and generate the other control signal based on the friction compensation value.