Control device and robot system
In teaching of a robot, a control device controls a movable unit in a first control mode in which the movable unit continuously moves according to a force detected by a force detector and a second control mode in which the movable unit moves by a predetermined movement amount according to the force detected by the force detector. A controller selects a first control mode or a second control mode according to a temporal change in the force detected by the force detector and a magnitude of the force.
1. A control device that controls a robot including a movable member and a force detector that detects a force applied to the movable member, the control device comprising:
a memory configured to store a program, a predetermined movement amount of the movable member, a force threshold, and a continuous time threshold; and
a processor configured to execute the program so as to perform a teaching mode, in the teaching mode, the processor being configured to:
cause the force detector to detect a force value of the force when the force is applied to the movable member along a force application direction, the force being generated due to one of moving, pushing, pulling, or twisting of the movable member by an operator;
obtain the force value from the force detector;
determine whether the force value is equal to or more than the force threshold while preventing a movement of the movable member even if the force is applied to the movable member;
detect a first period of time during which the processor determines that the force value is continuously equal to or more than the force threshold;
detect a second period of time that elapses from a time at which the processor determines that the force value is equal to or more than the force threshold;
determine whether the detected first period of time is equal to or more than the continuous time threshold;
continuously move the movable member along the force application direction from a first initial stop position as a continuous movement when the processor determines that the force value is equal to or more than the force threshold and the detected first period of time is equal to or more than the continuous time threshold and after the detected second period of time reaches the continuous time threshold;
end the continuous movement of the movable member when the processor determines that the force value is less than the force threshold; and
move the movable member along the force application direction by the predetermined movement amount from a second initial stop position as a fixed amount movement when the processor determines that the force value is equal to or more than the force threshold and the detected first period of time is less than the continuous time threshold and after the detected second period of time reaches the continuous time threshold.
2. The control device according to claim 1 , wherein
the force threshold includes a first value and a second value larger than the first value, and
in the fixed amount movement, the processor is configured to move the movable member by a first movement amount when the force value is equal to or more than the first value and is less than the second value, and the processor is configured to move the movable member by a second movement amount larger than the first movement amount when the force value is equal to or more than the second value.
3. The control device according to claim 1 , further comprising:
an input receiver configured to receive an input of the force threshold from the operator.
4. A robot system comprising:
a robot including a movable member and a force detector that detects a force applied to the movable member; and
a control device, the control device including:
a memory configured to store a program, a predetermined movement amount of the movable member, a force threshold, and a continuous time threshold; and
a processor configured to execute the program so as to perform a teaching mode, in the teaching mode, the processor being configured to:
cause the force detector to detect a force value of the force when the force is applied to the movable member along a force application direction, the force being generated due to one of moving, pushing, pulling, or twisting of the movable member by an operator;
obtain the force value from the force detector;
determine whether the force value is equal to or more than the force threshold while preventing a movement of the movable member even if the force is applied to the movable member;
detect a first period of time during which the processor determines that the force value is continuously equal to or more than the force threshold;
detect a second period of time that elapses from a time at which the processor determines that the force value is equal to or more than the force threshold;
determine whether the detected first period of time is equal to or more than the continuous time threshold;
continuously move the movable member along the force application direction from a first initial stop position as a continuous movement when the processor determines that the force value is equal to or more than the force threshold and the detected first period of time is equal to or more than the continuous time threshold and after the detected second period of time reaches the continuous time threshold;
end the continuous movement of the movable member when the processor determines that the force value is less than the force threshold; and
move the movable member along the force application direction by the predetermined movement amount from a second initial stop position as a fixed amount movement when the processor determines that the force value is equal to or more than the force threshold and the detected first period of time is less than the continuous time threshold and after the detected second period of time reaches the continuous time threshold.
5. A control device that controls a robot including a movable member and a force detector that detects a force applied to the movable member, the control device comprising:
a memory configured to store a program, a predetermined movement amount of the movable member, a force threshold, a minimum time threshold, and a continuous time threshold, the minimum time threshold having a smaller value than the continuous time threshold; and
a processor configured to execute the program so as to perform a teaching mode, in the teaching mode, the processor being configured to:
cause the force detector to detect a force value of the force when the force is applied to the movable member along a force application direction, the force being generated due to one of moving, pushing, pulling, or twisting of the movable member by an operator;
obtain the force value from the force detector;
determine whether the force value is equal to or more than the force threshold while preventing a movement of the movable member even if the force is applied to the movable member;
detect a first period of time during which the processor determines that the force value is continuously equal to or more than the force threshold;
detect a second period of time that elapses from a time at which the processor determines that the force value is equal to or more than the force threshold;
determine whether the detected first period of time is equal to or more than the minimum time threshold;
determine whether the detected first period of time is equal to or more than the continuous time threshold;
continuously move the movable member along the force application direction from a first initial stop position as a continuous movement when the processor determines that the force value is equal to or more than the force threshold and the detected first period of time is equal to or more than the continuous time threshold and after the detected second period of time reaches the continuous time threshold;
end the continuous movement of the movable member when the processor determines that the force value is less than the force threshold; and
move the movable member along the force application direction by the predetermined movement amount from a second initial stop position as a fixed amount movement when the processor determines the force value is equal to or more than the force threshold and the detected first period of time is equal to or more than the minimum time threshold and after the detected second period of time reaches the minimum time threshold.
6. The control device according to claim 5 ,
wherein the continuous time threshold is at least 25% more than the minimum time threshold.
7. The control device according to claim 5 ,
wherein the minimum time threshold is in a range of 50 ms to 500 ms.