This dataset contains all experimental data that is shown and referenced within the paper "Automatic Preload Adaptation for Rack-and-Pinion Drives to Maximize Performance and Energy Efficiency".
Electrically preloaded rack-and-pinion drives are typically utilized in machine tools to precisely move heavy loads over long travel distances. In the state of the art, the preload torque is commonly set to a constant value during commissioning. This poses a conflict of objectives between maximizing performance and minimizing energy consumption. To resolve this, this publication presents a novel approach to automatically adapt the preload torque during operation. For this purpose, the established preload control is extended by a simple control law that adapts the preload torque to the current operating state within the permissible limits. This way, higher preload torques are only applied, if the resulting higher system stiffness is beneficial for the drive performance. Otherwise, the preload torque is reduced to save energy.
The automatic preload adaptation is experimentally validated on a test system with industry standard components. This involves both system-theoretical analyses and practical test scenarios.
The data are structured to correspond to the figures in the publication:
Fig. 3 Measurement data: Motor and table velocities for the mechanical frequency response analysis of different preload levels.
Fig. 3 Mechanical frequency response: Mechanical frequency response of the system for different preload levels.
Fig. 5 and 6 Measurement data: Preload torque, motor and table position for the open loop position control frequency response analysis of the three examined configurations.
Fig. 5 Position control frequency response: Open loop position control frequency response of the three examined configurations.
Fig. 6 Preload frequency response: Preload torque of the three examined configurations for the open loop position control frequency response.
Fig. 7 Compliance frequency response: Compliance frequency response of the three examined configurations.
Fig. 7 Measurement data: Linear direct drive force, target and table position for the compliance frequency response analysis of the three examined configurations.
Fig. 7 Preload frequency response: Preload torque of the three examined configurations for the compliance frequency response.
Fig. 8 P2P Motion: Planned trajectory, measured table position and preload torque for the three examined configurations for a point-to-point motion with 2 m/s² acceleration.
Fig. 9 Acceleration comparison: Planned trajectory, measured table position and preload torque for the four examined accelerations with preload adaptation.
Fig. 10 Milling process: Process force applied by the direct drive, path
error and preload torque of the three examined configurations for a simulated milling process.
In addition to the data shown in the publication, this dataset contains supplementary data to Fig. 8 and Fig. 9. In the publication Fig. 8 shows the comparison of the path error and preload torque of the minimum, maximum and adaptive preload exemplarily for a motion with an acceleration of 2 m/s².
The folder Additional PTP Accelerations contains comparable measurement data and the corresponding plots for the other referenced accelerations of 1 m/s², 3 m/s² and 4 m/s². These provide the basis for the data presented in the publication in Table 3.