Abstract: A robot controller for controlling a robot arm comprising: —a first space shaping module configured to provide a shaped first space target motion by convolving a first space target motion with an impulse train, where the first space target motion defines a target motion in a first reference space; —a second space shaping module configured to provide a shaped second space target motion by convolving a second target motion with the impulse train; where the second target motion defines the target motion in a second reference space; and —a motor controller module configured to generate motor control signals to the joint motors based on the shaped first space target motion and the shaped second space target motion. This makes it possible to dynamically adjust in which reference space the input shaping shall be performed whereby vibrations and deviation in one reference space caused by input shaping in another reference space can be reduced.

Abstract: A method is provided for vibration suppression, which is useful in systems with configuration dependent dynamic parameters. The method is a general and practical solution for obtaining a set of inputs to a dynamic system, which will result in reduced vibrational behavior. A novel discrete time buffer implementation is employed, which yields reduced vibration due to a constant unity sum of applied impulses. The method includes shaping a position input with a continuously updated filter and using numerical differentiation to obtain consistent feedforward derivatives without phase shift.

Abstract: A method and robot controller configured to obtain an inertia-vibration model of the robot arm. The inertia-vibration model defines a relationship between the inertia of the robot arm and the vibrational properties of said robot arm and have been by setting the robot arm in a plurality of different physical configurations and for each of said physical configurations of said robot arm obtaining the vibrational properties and the inertia the robot arm. The inertia-vibration model makes it possible to in a simple and efficient way to obtain the vibrational properties of different physical configurations of the robot arm whereby the robot arm can be controlled according to the vibrational properties of the robot arm. This makes it possible to reduce the vibrations of the robot arm during movement of the robot arm.

Abstract: A method and a robot controller for controlling a robot arm, where the robot arm comprises a plurality of robot joints connecting a robot base and a robot tool flange, where each of the robot joints comprises an output flange movable in relation to a robot joint body and a joint motor configured to move the output flange in relation to the robot joint body. The robot arm is controlled based on vibrational properties of at least one external object connected to the robot arm, where the vibrational properties are received via an external object installation interface by generating control signals for said robot arm based on a target motion and the received vibrational properties of the at least one external object, the control signal comprises control parameters for said joint motor.

Abstract: A method is provided for vibration suppression, which is useful in systems with configuration dependent dynamic parameters. The method is a general and practical solution for obtaining a set of inputs to a dynamic system, which will result in reduced vibrational behavior. A novel discrete time buffer implementation is employed, which yields reduced vibration due to a constant unity sum of applied impulses. The method includes shaping a position input with a continuously updated filter and using numerical differentiation to obtain consistent feedforward derivatives without phase shift.