A control method of a robot, the robot including a first member, a second member connected to the first member, a drive device configured to rotate or slide the second member with respect to the first member, and an end effector connected to the second member, wherein posture of the end effector is changed by drive of the drive device, the robot control method includes detecting, based on an output signal from an inertial sensor disposed on the end effector, a gravity influence amount indicating a degree of influence of gravity received by the end effector, determining, based on the detected gravity influence amount, a drive algorithm for the drive device from among a plurality of drive modes, and driving the drive device by the determined drive algorithm.

A robot safety weight compensation system and method calculate a difference between an estimated torque calculated by a dynamics model and a detected torque to form a weight tolerance. When the weight tolerance exceeds a predetermined trigger condition, an error notification is output, and the robot is brought to a safe state. When the weight tolerance is within a predetermined trigger condition, a weight compensation information is sent to correctly compensate the weight held by a robot.

An instrument drive unit includes a housing defining a central longitudinal axis; an inertial measurement unit disposed within the housing and configured to determine a pose of the instrument drive unit; and a controller disposed within the housing, the controller configured to receive the pose of the instrument drive unit from the inertial measurement unit and to generate a corrected output signal which compensates for the pose of the instrument drive unit.

The present process of controlling an industrial robot includes steps consisting of calculating, in the modules implemented by the central unit, a time-dependent composite setpoint defining articular forces and velocities, according to a target trajectory and to an operating mode; calculating, in modules implemented by the central unit, a behavior matrix which describes a desired behavior of the robot arm, defining directions along which the calculated composite setpoint is to be applied; calculating, in a module implemented by the in auxiliary unit, an articular force setpoint for controlling the axis controller module; and calculating, in the axis controller module implemented by the auxiliary unit, the control setpoints for the power units according to the articular force setpoint.

A process of controlling an industrial robot includes the steps of calculating, in a calculation module, a control articular force setpoint of the axis controller module; calculating, in an articular converter, the articular conversion matrix from articular positions; providing the axis controller module with the multi-dimensional external forces exerted on the effector; calculating, in the axis controller module, the vector of the articular forces; calculating, in the axis controller module, the current loop control setpoints, taking into account the articular force vector and the articular force setpoint; and calculating, in the axis controller module, the control setpoints for the power units according to the control setpoints for the current loops.

An angular transmission error identification system that identifies an angular transmission error of a speed reducer of a robot arm including a joint that is rotationally driven by a motor via the speed reducer, including an identification unit that calculates amplitude and phase parameters of an angular transmission error identification function, which is a periodic function that models an angular transmission error of the speed reducer and has the parameters, and identifies the error using the function, wherein the unit calculates an amplitude parameter corresponding to a gravitational torque current value which is a value acting on a joint when the error is identified using a first or second amplitude function according to a value of the gravitational torque current value, and calculates a phase parameter corresponding to the gravitational torque current value using a first or second phase function according to a value of the gravitational torque current value.

A method, system, and non-transitory, computer-readable medium are provided for estimating a direction of gravity with respect to a robot. The method includes rotating a first joint. A first torque information of the first joint is recorded during rotation of the first joint. A second joint is then rotated. A second torque information of the second joint is recorded during rotation of the second joint. The direction of gravity is then estimated with respect to the robot based on the first torque information and the second torque information. The method provides an efficient way for determining the direction of gravity with respect to the robot.

A method of determining a weight and a center of gravity of a load for a robot manipulator, the method including: gripping the load using an end effector; moving the load into a number n of distinct static poses; determining an external wrench wrench F.sub.ext for each of the n static poses; determining, in a base coordinate system, at least components of each external wrench F.sub.ext that indicate the external forces; determining a particular estimation of the weight of the load from a particular component pointing in a direction of a gravity vector from among the components of each external wrench F.sub.ext that indicate the external forces in the base coordinate system, and from a magnitude of the gravity vector; determining the weight of the load by averaging respective estimations of the weight of the load; determining estimations of coordinates of the center of gravity of the load for each of the n static poses based on the weight of the load or the particular estimation of the weight of the load determined for a particular static pose and based on the components of the external wrench F.sub.ext that indicate externally acting torques; and determining the center of gravity of the load by averaging respective estimations of coordinates of the center of gravity.

A picking apparatus in an embodiment includes: a gripper, an arm, a detector, and a control unit. The gripper picks and grips an object to be conveyed. The arm moves the gripper and causes the gripper to convey the object to be conveyed. The detector is attached to the arm and senses a force applied to the gripper. The control unit controls an operation of the gripper and the arm. The control unit includes a calculator and a subtractor. The calculator calculates a gravitational force and an inertial force applied to the gripper when the gripper grips and moves the object to be conveyed using an arithmetic expression including a coefficient determined in accordance with a mass of the object to be conveyed. The subtractor subtracts the gravitational force and the inertial force calculated by the calculator from a force applied to the gripper sensed by the detector.

A method, system, and non-transitory, computer-readable medium are provided for estimating a direction of gravity with respect to a robot. The method includes rotating a first joint. A first torque information of the first joint is recorded during rotation of the first joint. A second joint is then rotated. A second torque information of the second joint is recorded during rotation of the second joint. The direction of gravity is then estimated with respect to the robot based on the first torque information and the second torque information. The method provides an efficient way for determining the direction of gravity with respect to the robot.