## 4 Implementation and Validation DT in AS Ecosystem
* **Running scenarios for the pair: the robot and its DT--**the defined scenarios are run for both the robot and its DT, and the performance metrics are recorded. This step provides valuable data about the behaviour of the DT under different conditions, which can be compared with the real-world system performance. * **Comparative analysis between the real robot's behaviour and that of the DT--**by examining the differences in performance metrics, areas of discrepancy and improvement can be identified. The DT can be considered validated if the discrepancies are within acceptable tolerances. Otherwise, it is necessary to take the next step. * **Calibration and adjustments of the DT--**adjust the parameters and settings of the DT to match the real-world system. This may include tuning the pneumatic actuator's characteristics, control logic, and environmental conditions. By performing multiple iterations, the parameters are adjusted until the DT accurately represents the real system's behaviour. * **Resumption of tests from the third step--**once the DT has been recalibrated, the working scenarios are run again with the updated values. This step validates the changes made during recalibration and ensures that the DT more closely represents the real system. * **Iterate and improve--**in this last stage, the validation of the DT is understood, as is continuously updating the DT with new data from the real system and adjusting its parameters accordingly, ensuring that the DT remains a reliable and effective representation of the real system. This iterative process is vital for the DT to remain a valuable tool for the design, simulation, optimisation, and control strategy testing tasks. Employing this systematic approach streamlines the validation process for the DT pneumatic robot, ensuring its accurate representation of the real-world system and enhancing its efficacy in design, simulation, and optimisation tasks. Although the validation model has been specifically applied to a pneumatic robot, it can be generalised to accommodate other mechatronic systems with the DTs created in diverse software platforms that encompass physical properties while allowing access to the analytical and dynamic aspects. This versatility expands the scope of the validation process, making it applicable to a diverse array of mechatronic systems featuring DTs. The sequence corresponding to the graph depicted in Figure 9 was carried out at the macro level for both the robot and its DT. The robot returns to its homing point when the user presses the \"Start\" button. In the home pose configuration, the robot has the gripper closed, rotated to the left, completely backward, and has the cylinder responsible for lifting the robot chassis positioned at 10 mm. In the following state of the graph, the robot transitions from its home pose to a new state in which the cylinder responsible for lifting the robot chassis (U/D cylinder) raises it to its maximum height of 200 mm. This movement represents a change in the robot's position and a step towards executing the defined sequence. After reaching the maximum height, the next step in the sequence involves the bilateral F/B cylinder moving forwards. This action represents a further change in the robot's position and continues the execution of the defined sequence. Figure 10 captures snapshots at various moments during the execution of the working scenario, with the real robot in the background and its digital twin displayed on the monitor in the foreground. These snapshots provide a visual comparison of the robot's behaviour and the digital twin's performance throughout the scenario, further highlighting the accuracy and effectiveness of the digital twin in replicating the real system. A rough analysis can be conducted by observing the movements of the real robot and its digital twin in parallel. This qualitative comparison identifies any major discrepancies in motion and behaviour, providing an initial assessment of the DT's accuracy in replicating the real system.