Abstract: A robot, such an industrial robot, has an arm. The arm has a plurality of rotation members, a plurality of joints each rotatably and mutually connecting adjacent two rotation members, and a plurality of electric servo motors respectively driving the joints. In this robot, every operation cycle, an angular speed is calculated at which to drive each servo motor, and a speed of a monitoring portion set in each rotation member is calculated. It is then determined whether or not the speed at the monitoring portion is equal to or lower than a reference speed. When it is determined that the speed at the monitoring portion is over the reference speed, the angular speed of each servo motor is instructed to reduce such that the speed at each monitoring portion becomes the reference speed or lower. The servo motors are driven at the angular speed that has been reduced.

Abstract: A robot, such an industrial robot, has an arm. The arm has a plurality of rotation members, a plurality of joints each rotatably and mutually connecting adjacent two rotation members, and a plurality of electric servo motors respectively driving the joints. In this robot, every operation cycle, an angular speed is calculated at which to drive each servo motor, and a speed of a monitoring portion set in each rotation member is calculated. It is then determined whether or not the speed at the monitoring portion is equal to or lower than a reference speed. When it is determined that the speed at the monitoring portion is over the reference speed, the angular speed of each servo motor is instructed to reduce such that the speed at each monitoring portion becomes the reference speed or lower. The servo motors are driven at the angular speed that has been reduced.

Abstract: In an axis angle determination method, an angle or a position of each axis of a six-axis robot is determined. The robot is capable of taking an attitude of a singular point being a state in which rotation axes of fourth and sixth axes match. Based on teaching results of a position and attitude of a hand by point-to-point teaching, the method judges whether an attitude of the robot in which the angle or the position of each angle is to be determined next is a singular point. If judged that the attitude is the singular point, angles of the fourth and sixth axes required for the six-axis robot to move to the singular point are determined such that an angle of one of the fourth and sixth axes is fixed to a current value and an angle of the other axis is determined based on the fixed angle.

Abstract: In an axis angle determination method, an angle or a position of each axis of a six-axis robot is determined. The robot is capable of taking an attitude of a singular point being a state in which rotation axes of fourth and sixth axes match. Based on teaching results of a position and attitude of a hand by point-to-point teaching, the method judges whether an attitude of the robot in which the angle or the position of each angle is to be determined next is a singular point. If judged that the attitude is the singular point, angles of the fourth and sixth axes required for the six-axis robot to move to the singular point are determined such that an angle of one of the fourth and sixth axes is fixed to a current value and an angle of the other axis is determined based on the fixed angle.

Abstract: In a 6-axis robot, as an example, an inter-axis offset can be measured and calibrated. A light emitting diode is installed on an end effector, and the end effector is located on a plurality of target positions of movement on the axis X (Xb) of a robot coordinate. Then, the position of the light emitting diode is measured by a three-dimensional gauge, and an inter-axis offset F is detected based on an error between the target positions of movement and actually moved positions. For the inter-axis offset F, DH parameters are calibrated.

Abstract: A calibrating technique is provided for the position/attitude or only the position of an arm tip of a robot, such as an articulated type of robot. At plural positions, respective n pieces of errors (??n, wherein n is a positive integer larger than a value obtained by dividing the number of unknown parameters by 6 or 3) are calculated. Each error is a difference between a position of the arm tip measured and a position commanded by control. An inter-error difference (??y (1?y?n?1)) between a reference error (??m (1?m?n)) arbitrarily selected from the n-piece errors (??n) and other errors (??x (x?n, except for m)) other than the reference error (??m) is calculated. A parameter, which is a basis for calculating the inter-error differences (??y), is made to converge until a sum of absolute values of the inter-error differences (??y) becomes within a given threshold (?0 (?0>0)).

Abstract: In a 6-axis robot, as an example, an inter-axis offset can be measured and calibrated. A light emitting diode is installed on an end effector, and the end effector is located on a plurality of target positions of movement on the axis X (Xb) of a robot coordinate. Then, the position of the light emitting diode is measured by a three-dimensional gauge, and an inter-axis offset F is detected based on an error between the target positions of movement and actually moved positions. For the inter-axis offset F, DH parameters are calibrated.

Abstract: A calibrating technique is provided for the position/attitude or only the position of an arm tip of a robot, such as an articulated type of robot. At plural positions, respective n pieces of errors (??n, wherein n is a positive integer larger than a value obtained by dividing the number of unknown parameters by 6 or 3) are calculated. Each error is a difference between a position of the arm tip measured and a position commanded by control. An inter-error difference (??y (1?y?n?1)) between a reference error (??m (1?m?n)) arbitrarily selected from the n-piece errors (??n) and other errors (??x (x?n, except for m)) other than the reference error (??m) is calculated. A parameter, which is a basis for calculating the inter-error differences (??y), is made to converge until a sum of absolute values of the inter-error differences (??y) becomes within a given threshold (?0 (?0>0)).