A screwing device including: a container for screws; a manipulator having an effector to pick up a screw; an isolating unit connected to the container to provide the screw from the container at an interface such that a head of the screw is accessible to the effector; and a control unit to control the manipulator in executing a control program to perform operations including: guiding the effector along a trajectory having an orientation to the screw head at the interface, wherein the orientation is defined for locations along the trajectory; and executing force-regulated, impedance-regulated, and/or admittance-regulated periodic and closed tilting movements of the effector in relation to its orientation until a condition for a torque, a force, or a time for carrying out the tilting movements is reached or exceeded, and/or a force/torque and/or a position/speed signature at the effector is reached or exceeded, indicating successful pick-up of the screw.

A nut runner, an attachment unit, and a sliding member are provided in a second arm that is a leading arm of the robot and has a leading end shaft movable along the direction of an elevation axis. The nut runner includes a screw fastening driver, a drive shaft rotationally driven by the screw fastening driver, and an extension bar that is so connected to rotate together with the drive shaft in the circumferential direction and to move in the axial direction. The attachment unit fixedly connects the screw fastening driver to the second arm so that a screw fastening axis parallel to the elevation axis serves as a rotation axis of the screw fastening driver. The sliding member is connected to the leading end shaft and supports the extension bar so as to move together in the axial direction and are rotatable relatively in the circumferential direction.

A method for measuring an axial-force of a bolt fastened to a component to be fastened, includes temporarily fastening the bolt to the component to be fastened with a temporarily-tightening torque, the temporarily-tightening torque being a torque which is determined in advance and by which a depression is formed on a head of the bolt, measuring a first axial force of the temporarily-fastened bolt, regularly fastening the bolt to the component to be fastened with a regularly-tightening torque, the regularly-tightening torque being torque which is determined in advance and larger than the temporarily-tightening torque, measuring a second axial force of the regularly-fastened bolt, and measuring an estimated axial force of the regularly-fastened bolt by using the torque with which the bolt is temporarily fastened, the torque with which the bolt is regularly fastened, and a difference between the first and second axial forces.

A method of controlling a robot that performs work using an end effector on an object transported by a handler includes calculating a target position of the end effector based on a position of the object, calculating a tracking correction amount for correction of the target position in correspondence with a transport amount of the object, controlling the end effector to follow the object based on the target position and the tracking correction amount, acquiring an acting force acting on the end effector from the object using a force sensor, calculating a force control correction amount for correction of the target position to set the acting force to a target force, and controlling the acting force to be the predetermined target force by driving the manipulator based on the force control correction amount.

A wheel nut engagement checking system for a vehicle delivered by a conveyor includes: a moving member disposed at one side of the conveyor; a wheel lifting apparatus disposed on the moving member, and lifting a wheel of the vehicle from the conveyor to a predetermined height; a wheel nut torque checking apparatus provided on an arm of a robot disposed on the moving member, engaging a nut runner to a wheel nut of the wheel, and checking an engage torque of the wheel nut by rotating the nut runner; and a controller controlling a speed of the moving member, lifting the wheel to the predetermined height using the wheel lifting apparatus, moving the wheel nut torque checking apparatus using the robot so as to engage the nut runner to the wheel nut, and detecting an engage torque of the wheel nut by rotating the nut runner.

A robot control system includes a robot that screw-fastens a sub-component placed in a main-component to the main-component, a robot control unit that controls the robot, and a display as an output unit through which the robot control unit outputs a message to an operator. The robot control unit determines whether or not the robot can screw-fasten the sub-component to the main-component by itself. Then, when the robot control unit determines that the robot cannot screw-fasten the sub-component to the main-component by itself, the robot control unit outputs a cooperation message to an operator through the display.

A screw tightening system includes an actuator including a driver bit that rotationally drives a screw and a motor coupled with driver bit, and a controller that controls actuator. Controller includes an acquirer that acquires torque values of a torque generated in a motor, a calculator that calculates a standard deviation of the torque values in a temporary tightening period, and a determiner that determines that there is an abnormality when a ratio of the standard deviation to a reference standard deviation exceeds a first threshold value.

A robot control system includes a robot that screw-fastens a sub-component placed in a main-component to the main-component, a robot control unit that controls the robot, and a display as an output unit through which the robot control unit outputs a message to an operator. The robot control unit determines whether or not the robot can screw-fasten the sub-component to the main-component by itself. Then, when the robot control unit determines that the robot cannot screw-fasten the sub-component to the main-component by itself, the robot control unit outputs a cooperation message to an operator through the display.

An automatic test device (10) for testing automatic screwdrivers (12) in a robotic station (10) for tightening elements (18) of an object (17) handled in the station comprises a frame (20) suitable for being inserted in a station in place of an object handled in the station; a plurality of screwdriver test heads (21) arranged on the frame (20); a control unit (24) connected to the test head (21) in order to control operation of the test heads (21) and detect tightening parameters of screwdrivers applied to the test heads (21) by the robotic station.

A plant with at least one robotic station (10), a transport line (15) and an automatic test device (10) is also described. Finally, a method for testing automatic screwdrivers in robotic stations is described.

A control device adapted to control a robot including a robot arm provided with a force detector includes a processor that is configured to execute computer-executable instructions so as to control the robot, wherein the processor is configured to: operate the robot arm to move a screw gauge which is disposed on a tip side of the force detector of the robot arm, used for an inspection of a screw hole, and provided with an external thread, to make the external thread have contact with the screw hole; then detect force applied to the screw gauge using the force detector to perform force control in a direction perpendicular to a direction of an axis of the screw hole based on detection information of the force detector; and operate the robot arm to move the screw gauge based on the force control.