Using Virtual Sensors in Industrial Manipulators for Service Algorithms Like Payload Checking

Industrial manipulators are usually equipped with a set of basic sensors (encoders and current sensors) that could not be sufficient to implement more advanced service and control algorithms, like the Payload Check, the Impedance Control or the Cartesian Soft Servo. A software layer between the real sensors and the algorithms is developed in order to provide a new set of “measures”. Such a layer, called Virtual Sensor, exploits the information provided by the real sensors to compute new virtual measures, to be used in the algorithms layer to implement new services. The Virtual Sensor is introduced in a standard COMAU controller and its effectiveness is tested in a service algorithm, called Payload Check, able to detect a wrong declaration of the robot payload. Good performances have been obtained for a wide range of COMAU manipulators.