Xiaohu Sun

This study presents an optimized design and vision-guided control strategy for a multi-functional robotic gripper integrated into an automatic loading system for warehouse environments. The system adopts a modular architecture, including standardized platforms, transport containers, four collaborative 6-DOF robotic arms, and a multi-sensor vision module. Methodologically, we first developed three gripper prototypes, selecting the optimal design (30° angle between the gripper and container side) through workspace and interference analysis. A deep vision-based recognition system, enhanced by an improved YOLOv5 algorithm and multi-feature fusion, was employed for real-time object detection and pose estimation. Kinematic modeling and seventh-order polynomial trajectory planning ensured smooth and precise robotic arm movements. Key results from simulations and experiments demonstrated a 95.72% success rate in twist lock operations, with a positioning accuracy of 1.2 mm. The system achieved a control cycle of 35 ms, ensuring efficiency compared with non-vision-based methods. Practical implications include enabling fully autonomous container handling in logistics, reducing labor costs, and enhancing operational safety. Limitations include dependency on fixed camera setups and sensitivity to extreme lighting conditions.

In this paper, a brake cylinder coating comprising a composite material of an Fe₃Al and Cr₃C₂ mixed powder was prepared by adding laser cladding onto carbon structural steel. We studied the influence of process parameters on the microstructure and tribological properties of the cladding materials using scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and 3D white light interferometer and wear tests. The influence of different processes on the morphology of the carbide strengthening phase was found to be relatively small with a Cr₃C₂ content of 15 wt.%. The carbides mainly exhibited a network structure in each group of cladding layers. The area of the network strengthening phase varied under different processes. Of the cladding layers formed with different processes, the scanning speed of the 0.003 m/s cladding layer had the lowest wear rate. When the laser power was too low or the powder feed rate was too high, unmelted Cr₃C₂ particles could be found in the cladding layer. During the wear process, the particles peeled off, causing severe abrasive wear. When the powder feeding rate was too low, more materials in the base material entered the cladding layer. This made the composition of the cladding layer similar to that of the grinding material, resulting in severe adhesive wear.