Robot gearboxes are usually replaced after fixed maintenance intervals, either after a certain period of operation or a fixed period of time, regardless of actual wear. Gearbox specialist Nabtesco wants to counteract this approach and is launching a predictive maintenance project. This is because robot gearboxes are exposed to different levels of stress depending on the application requirements, duration of use and task area; moreover, the individual axes are not subjected to the same level of stress.

This is where the cycloidal gearbox specialist comes in: with a Nabtesco add-on for the robot controller, it provides robot manufacturers with gearbox-specific data and characteristics, i.e. a digital image of the gearbox with its relevant properties. The real serial number-related digital gearbox characteristics are of central importance for real-time monitoring of robots, as they enable an individual snapshot of the robot utilization and thus a view of the remaining service life of the individual gearboxes.

Work is carried out with values that are already available: For example, the speed and torque curve allows detailed conclusions to be drawn about the condition of the gearbox and therefore its remaining service life. With permanent monitoring of the cycloidal gears, maintenance could be carried out as required. Impending failures could be detected early, service calls could be planned and unplanned machine downtimes could be avoided.

Software-based maintenance concept and digital services

According to the company, the software-based solution offers advantages over external sensors, including cost reduction, reduced system complexity and better data quality. Another point: not all data can be recorded using external sensors. This applies, for example, to stiffness as well as to empirical values from development.

The project is currently in the development phase. Two stages are planned: a Nabtesco add-on with generalized data of a specific gearbox model and an additional upgrade for even greater accuracy with the specific data of the gearboxes that are ultimately installed.