Robot system with stored position information of sensor

1 . A robot system comprising:

a first link that is a part of a robotic arm;

a first motor that moves according to a rotation of the first link;

a first sensor having a fixed location with respect to the first motor;

a memory configured to store first position information indicating a relative position of the first sensor with respect to the first motor; and

circuitry configured to:

correct first sensor information acquired from the first sensor based on the first position information and status information of the first link; and

control the robotic arm based on the corrected first sensor information.

2 . The robot system according to claim 1 , further comprising a second link that is a part of the robotic arm,

wherein the first link is connected to the second link and rotatable with the second link,

wherein the circuitry is configured to correct the first sensor information acquired from the first sensor based on the first position information, the status information of the first link, and status information of the second link.

3 . The robot system according to claim 1 , further comprising:

a second motor configured to rotate a part of the robotic arm including the first link; and

a second sensor having a fixed location with respect to the second motor,

wherein the memory further stores second position information indicating a relative position of the second sensor with respect to the second motor, and

wherein the circuitry is configured to correct second sensor information acquired from the second sensor based on the second position information.

4 . The robot system according to claim 3 , wherein each of the first sensor and the second sensor is an acceleration sensor, and

wherein the circuitry is further configured to:

calculate a component that is included in the corrected first sensor information and that is related to the corrected second sensor information, based on the corrected second sensor information, motion of the part of the robotic arm caused by the second motor, and the first position information; and

calculate relative sensor information by excluding the calculated component from the corrected first sensor information.

5 . The robot system according to claim 3 ,

wherein the circuitry is further configured to:

detect a vibration of the first sensor based on the corrected first sensor information;

detect a vibration of the second sensor based on the corrected second sensor information;

calculate relative vibration by excluding a vibration component related to the detected vibration of the second sensor from the detected vibration of the first sensor; and

control the robotic arm to reduce the relative vibration.

6 . The robot system according to claim 5 , wherein the first sensor moves in a movement direction together with the first motor when the first link is rotated by the second motor,

wherein the circuitry is configured to calculate the relative vibration including a main relative vibration that occurs in the movement direction, and

wherein the circuitry is configured to control the second motor to reduce the main relative vibration.

7 . The robot system according to claim 6 , wherein the first sensor moves in a direction intersecting the movement direction when the first link is rotated by another motor,

wherein the circuitry is configured to calculate the relative vibration including a sub relative vibration that occurs in the direction intersecting the movement direction, and

wherein the circuitry is further configured to control the other motor to reduce the sub relative vibration.

8 . The robot system according to claim 3 , wherein the circuitry is further configured to detect torsion of the first link based on the corrected first sensor information and the corrected second sensor information.

9 . The robot system according to claim 1 , wherein the circuitry is configured to correct the first sensor information into a coordinate system that is independent of a posture of the first sensor based on the first position information and a rotational angle of the first link.

10 . The robot system according to claim 1 , wherein the circuitry is configured to correct the first sensor information to be independent of a rotational acceleration of the first link based on the first position information and the rotational acceleration of the first link.

11 . The robot system according to claim 1 , wherein the circuitry is configured to correct the first sensor information to be independent of a rotational speed of the first link based on the first position information and the rotational speed of the first link.

12 . The robot system according to claim 1 , further comprising a first encoder fixed to the first motor and configured to detect rotation of the first motor,

wherein the first sensor is built into the first encoder.

13 . The robot system according to claim 12 , wherein the first encoder comprises an integrated circuit configured to calculate a rotational angle of the first motor, and

wherein the first sensor is included in the integrated circuit.

14 . The robot system according to claim 13 , wherein the first sensor comprises:

a sensor head configured to convert a sensing target into an analog signal; and

an AD conversion circuit configured to convert the analog signal into a digital signal.

15 . The robot system according to claim 1 , further comprising one or more other motors each configured to drive the robotic arm including the first link,

wherein the first sensor is an acceleration sensor, and

wherein the circuitry is further configured to:

calculate a component that is included in the first sensor information and that is related to a motion of the first link generated by the one or more other motors based on a status of the one or more other motors and the first position information; and

calculate the corrected first sensor information by excluding at least part of the calculated component from the first sensor information.

16 . A robot system comprising:

a robotic arm link;

a motor that moves according to a rotation of the robotic arm link;

an acceleration sensor having a fixed location with respect to the motor;

a memory configured to store position information indicating a relative position of the acceleration sensor with respect to the motor; and

circuitry configured to correct sensor information acquired from the acceleration sensor based on the position information and status information of the robotic arm link.

17 . The robot system according to claim 16 , further comprising a torque sensor,

wherein the circuitry is configured to interpolate torque information acquired by the torque sensor based on the corrected first sensor information.

18 . The robot system according to claim 16 , further comprising a contact sensor configured to detect contact with a peripheral object,

wherein the circuitry is configured to add an acting direction of a reaction force from the peripheral object to contact information acquired by the contact sensor, based on the corrected sensor information.

19 . A robot system comprising:

a first link that is a part of a robotic arm;

a first motor that moves according to a rotation of the first link;

a first sensor having a fixed location with respect to the first motor;

a second motor configured to rotate a part of the robotic arm including the first link;

a second sensor having a fixed location with respect to the second motor;

a memory configured to store first position information indicating a relative position of the first sensor with respect to the first motor and second position information indicating a relative position of the second sensor with respect to the second motor; and

circuitry configured to:

calculate a relative vibration of the first sensor relative to the second sensor based on first sensor information acquired from the first sensor, second sensor information acquired from the second sensor, the stored first position information, and the stored second position information; and

control the robotic arm to reduce the relative vibration.

20 . The robot system according to claim 19 , wherein the circuitry is further configured to:

detect a vibration of the first sensor based on the first sensor information; and

detect a vibration of the second sensor based on the second sensor information, and

wherein the relative vibration is calculated by excluding a vibration component related to the detected vibration of the second sensor from the detected vibration of the first sensor.