Shopfloor digital twin and its application in HRC scenarios
Digital twin, as the name suggests, is the representation of a given cell, robot or even, operator, in the digital world. With the use of multiple sensors, enough data can be collected so this digital representation as close to the real world as possible.
In SHERLOK, such concept is wrapped around the Shopfloor Digital Representation (SDR). SDR is a novel, multiple purpose, digital twin architecture, enabling precise representation and quick adaption to new cells. During the development of the module, a framework has been developed to precisely set up the environment on the digital world. A set of libraries and functions has been developed and used, so any end user will be able to create the digital representation of his application, with the minimum effort.
The resulting digital replica of the real world uses a distributed sensor network and ROS (Robotics Operating System) to collect data from the environment and inform the digital twin about any changes (e.g. an operator is in the cell). SDR, using these data, can control the cell processes, enable safety functionalities under pre-programmed conditions and adapt the robot behavior according to the operator needs, contributing to the seamless Human Robot Collaboration (HRC).
Even though the online functionality of the SDR is useful for the adaption of the cell need to the dynamic environment, the same module can be used in offline mode. In this mode, there is no need of a real-world cell. Every environment parameter is simulated into the digital twin and the end user can see how the configured setup will respond to various conditions. This is a powerful tool during the cell layout design and validation. During the design process, the cell is designed in the digital world only, simulating the robot kinematics and operator action. After each simulation, KPIs regarding the operator and the cobot are collected and used to validate the efficiency of a certain design, in a time and cost-effective manner.
The internal architecture of the SDR is designed to be fully modular, providing the ability to any user to add and remove functionalities (gripper controls, planning scene, operator ergonomics evaluation) with the minimum development effort. The modular architecture also enables us to quickly integrate the SDR with any other software module (robot driver, safety monitoring modules, etc.).
All the above were developed and validated within the SHERLOCK Project. The module was used in four use case scenarios, with High and Low Payload Collaborative Manipulators as wel as mobile robots, while and tested in industrial environments. Even though the SDR was a research outcome, it proved to be quite robust and easily configurable on the field. As for the future, the module will be enhanced with more functionalities, such as predictive maintenance, logistics functionalities and cost calculations, that will further integrate the module in a factory level.