A 4 Degrees of Freedom Cartesian Robot for Automated Compaction Mold Handling and Measurement

To simulate actual field conditions in fabricating roller-compacted concrete (RCC) specimens, various compaction methods, such as the vibrating table, vibrating hammer, and modified Proctor, typically use a cylindrical mold. As no prior research has focused on automating the post-compaction processes, including mold manipulation, soil trimming, and mass measurement, this study presents a 4-DoF Cartesian robot with three linear joints and one rotary joint to automate these tasks. The robot performs four key operations: unscrewing the collar extension of a three-part compaction mold with a rotary tool, picking up the extension collar with a second arm, returning the mold to clean the excess soil, and measuring the mold and specimen’s mass using an integrated load cell. The mold is then positioned at the center of the robot’s X-axis, displaying the measured mass on an LCD. A force of 133.33 N was applied to the rotary tool, driven by a stepper motor with a torque of 2.4 N. A stress analysis revealed a maximum stress of 5 MPa on the rotary tool, well below the material’s yield strength of 280 MPa, ensuring the system’s structural integrity.