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US 11,305,431 B2Granted
System and method for instructing a robot
AssigneeCognibotics AB
InventorsM. Mahdi Ghazaei Ardakani, Klas Nilsson
Life of this patent
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Abstract
The disclosure relates to a system (1) and method for instructing a robot. The system (1) comprising an immersive haptic interface, such that operator interaction with a master robot arm (2) is reflected by a slave robot arm (3) arranged for interaction with a workpiece (4). The interaction of the slave robot arm (3) is reflected back to the master robot arm (2) as haptic feedback to the operator. The dynamic system is continually simulated forward and new commands are calculated for the master robot arm and the slave robot arm.
Claims25
A system, comprising:
- a robot having a master robot arm configured for being operably influenced by interaction with an operator;
- and a slave robot arm, configured for interaction with a workpiece;
- and
- a control unit configured to determine master external-force data indicating a force interplay between the operator and the master robot arm, and to determine slave external-force data indicating a force interplay between the slave robot arm and the workpiece;
- wherein the control unit further comprises a haptic interface module, comprising:
- a constraint submodule defining a plurality of motion constraints including a kinematic coupling in a task space between a designated master coupling frame of the master robot arm and a designated slave coupling frame of the slave robot arm, such that a velocity of the master coupling frame and a velocity of the slave coupling frame are interrelated in the task space;
- and
- a calculation submodule configured to calculate a joint movement command for the master robot arm and a joint movement command for the slave robot arm, based on the master external-force data, the slave external-force data, a non-linear dynamic model of the master robot arm, a non-linear dynamic model of the slave robot arm, a relationship between the non-linear dynamic model of the master robot arm and the non-linear dynamic model of the slave robot arm including virtual forces or torques at the designated master coupling frame and the designated slave coupling frame for the kinematic coupling in the task space, and based on at least one virtual force or virtual torque needed to enforce the plurality of motion constraint, while preserving constraints imposed by the non-linear dynamic models of the master robot arm and the slave robot arm;
- wherein the system is configured to:
- control the master robot arm and the slave robot arm according to the joint movement commands, wherein during instruction of the robot, haptic feedback from the force interplay between the operator and the master robot arm and the force interplay between the slave robot arm and workpiece reflecting dynamics of the system is provided to the operator.
7 more elements
A method for instructing a robot comprising:
- determining master external-force data indicating a force interplay between an operator and a master robot arm of a robot;
- determining slave external-force data indicating a force interplay between a slave robot arm of the robot and a workpiece;
- calculating a joint movement command for the master robot arm and a joint movement command for the slave robot arm based on (i) the master external-force data, the slave external-force data, a first non-linear dynamic model of the master robot arm, a second non-linear dynamic model of the slave robot arm, and a plurality of motion constraints including a defined kinematic coupling in a task space between a designated master coupling frame of the master robot arm and a designated slave coupling frame of the slave robot arm, by enforcing a relationship between the first and second non-linear dynamic models, including virtual forces or torques at the designated frames for accomplishing the kinematic coupling in the task space, while respecting constraints imposed by the first and second non-linear dynamic models, resulting in that a velocity of the master coupling frame and a velocity of the slave coupling frame are interrelated in the task space, and (ii) at least one virtual force or virtual torque needed for enforcing the plurality of motion constraints;
- and
- controlling the master robot arm and the slave robot arm according to the joint movement commands, wherein during instruction of the robot, the operator receives haptic feedback from the force interplay between the operator and the master robot arm and the force interplay between the slave robot arm and workpiece reflecting dynamics of at least one of the master robot arm and the slave robot arm.
2 more elements
A non-transitory, computer-readable medium comprising instructions which, when executed by a control unit or a computer operatively connected to the control unit, cause the control unit to instruct a robot in accordance with a method comprising:
- determining master external-force data indicating a force interplay between an operator and a master robot arm of a robot;
- determining slave external-force data indicating a force interplay between a slave robot arm of the robot and a workpiece;
- calculating a joint movement command for the master robot arm and a joint movement command for the slave robot arm based on (i) the master external-force data, the slave external-force data, a first non-linear dynamic model of the master robot arm, a second non-linear dynamic model of the slave robot arm, and a plurality of motion constraints including a defined kinematic coupling in a task space between a designated master coupling frame of the master robot arm and a designated slave coupling frame of the slave robot arm, by enforcing a relationship between the first and second non-linear dynamic models, including virtual forces or torques at the designated frames for accomplishing the kinematic coupling in the task space, while respecting constraints imposed by the first and second non-linear dynamic models, resulting in that a velocity of the master coupling frame and a velocity of the slave coupling frame are interrelated in the task space, and (ii) at least one virtual force or virtual torque needed for enforcing the plurality of motion constraint;
- and
- controlling the master robot arm and the slave robot arm according to the joint movement commands, wherein during instruction of the robot, the operator receives haptic feedback from the force interplay between the operator and the master robot arm and the force interplay between the slave robot arm and workpiece reflecting dynamics of at least one of the master robot arm and the slave robot arm.
2 more elements
Dependencies are inferred from the claim text.