# Orbital-Based Automatic Multi-Layer Multi-Pass Welding Equipment for Small Assembly Plates
## 2 Design and Analysis of Rail-Mounted Automatic Welding Equipment
### Operational Logic and Workflow of the Equipment
#### 2.3.2 Workflow  
After the robotic arm is positioned at the origin, the upper computer controls the robotic arm to perform scanning and welding. During scanning, the robotic arm adopts a divide-and-conquer strategy: first obtaining the approximate outline of the entire fixture or target, then performing detailed scanning based on the type of plate to be processed. The upper computer conducts corresponding visual analysis of the entire fixture based on the scanning results; the visual analysis system employs algorithms such as extremum strategies, filtering, and cyclic verification. After processing, the upper computer statistically summarizes and generates the welding paths and, in coordination with the correspond  
Figure 15: Overall working logic diagram of equipment.  
ing welding processes, completes the actual welding of each path segment. The overall operational equipment diagram is shown in Figure 16.  
The detailed workflow of the equipment is as follows: Before operation, the robotic arm along with the external axis system can be set to manual, teach, or automatic modes. It can also perform demonstrations using welding simulation or trajectory simulation. During operation, the electric control cabinet remains powered on and is connected to the mobile control cabinet. The mobile control cabinet is equipped with a main control board, IO board, adapter board, laser module, switching power supply, network switch, power cables, and data cables. The main control board, adapter board, and IO board are responsible for receiving externally input discrete signals, analog signals, and digital signals. The network switch connects the upper computer (HMI) to the adapter board; signals are transmitted to the main control board via communication protocols, completing the overall information transmission process. The equipment's welding cables, communication cables, and sensors adopt protective designs using auxiliary fixtures and protective covers. After welding, the database can be updated and iterated according to different working condition types, and new scanning strategies and welding processes can be formulated. In terms of technical features, the working modes of the rail-mounted automatic welding equipment can be divided into three types: upright installation, inverted installation, and side installation. Due to the stability requirements of welding conditions and the need for specific welding postures, this design adopts the upright installation arrangement. The specific type analysis is shown in Table 5.  
Figure 16: Overall operating equipment summary diagram.  
\begin{table}
\begin{tabular}{c c c c} \hline
**Working Method** & **Applicable Scene** & **Vantage** & **Limitations** \\ \hline Installed above the track & Specified range welding & Stabilization & Localised movement restricted \\ Installed under the track & Automatic handling & Wide operating range & Load capacity limited \\ Installed on the side of the track & Automated assembly & High working accuracy & Complex installation and maintenance \\ \hline \end{tabular}
\end{table}
Table 5: Job type detail.