Closed loop identification of an industrial robot of the type ABB IRB 1400 is considered. Using data collected when the robot is subject to feedback control and moving around axis one linear black-box and physically parameterized models are identified. A main purpose is to model the mechanical flexibilities and it is found that the dynamics of the robot can be well approximated by a model consisting of three-masses connected by springs and dampers. It also found that the results of the identification depend on the properties of the input signal. Keywords: identification, robotics, flexible arms Closed Loop Identification of an Industrial Robot Containing FlexibilitiesMånsÖstring, Svante Gunnarsson * , Mikael Norrlöf Department of Electrical Engineering, Linköping University, SE-58183 Linköping, Sweden AbstractClosed loop identification of an industrial robot of the type ABB IRB 1400 is considered. Using data collected when the robot is subject to feedback control and moving around axis one linear black-box and physically parameterized models are identified. A main purpose is to model the mechanical flexibilities and it is found that the dynamics of the robot can be well approximated by a model consisting of three-masses connected by springs and dampers. It also found that the results of the identification depend on the properties of the input signal.

Recursive identification of physically parameterized models of continuous time systems is considered. As an example a model of a single link flexible robot arm is considered. The aim of the identification is to generate on-line estimates of physical parameters that can be used for, e.g., diagnosis purposes. For evaluation the algorithm is applied to data from an industrial robot, and three important parameters are identified using only measurements of the motor angle. Keywords: Robotics, Recursive identification, Physical parameters AbstractRecursive identification of physically parameterized models of continuous time systems is considered. As an example a model of a single link flexible robot arm is considered. The aim of the identification is to generate on-line estimates of physical parameters that can be used for, e.g., diagnosis purposes. For evaluation the algorithm is applied to data from an industrial robot, and three important parameters are identified using only measurements of the motor angle.

This paper covers modeling and identification of one joint of an industrial robot manipulator including flexibilities. It is shown how models can be built in the Modelica graphical environment and how these models can be transformed into a mathematical state space description which directly can be used for identification. A motivation to use linear models for modeling of the robot arm is given. This includes an analysis of the nonlinearities in the input/output data from the actual robot using a special kind of input signal. Identification and validation of the physically parameterized models are also covered.