Core Viewpoint - The Jinan Metro Line 4 has officially started its empty test run, with plans to be completed and operational by the end of the year. The key to ensuring operational safety lies in the joint debugging and testing process, carried out by a dedicated team of engineers known as "metro doctors" [1]. Group 1: Joint Debugging and Testing Process - The debugging work is divided into two main sections: station debugging and train operation debugging, covering numerous systems such as ventilation, air conditioning, and signaling, all crucial for train safety and punctuality [4]. - The debugging team, led by Song Zengqing, has been involved since August of last year, overseeing the entire process from the first station's debugging to the empty test run [2]. - A thorough inspection process, referred to as "carpet-style" checks, was conducted to identify potential safety hazards, emphasizing the importance of attention to detail [4][6]. Group 2: Testing Scenarios and Requirements - The debugging process involves 45 major testing scenarios and over 1,200 testing points, with signal debugging accounting for 70%-80% of the total [7]. - Each command in the fully automated operation mode must be executed with precision, ensuring that trains stop accurately at stations and emergency protocols are triggered correctly [7]. - The most complex test involves "multi-train tracking," where up to seven trains are tested simultaneously in the tunnel, requiring precise calculations of speed and position to ensure safety [9]. Group 3: Commitment to Safety and Quality - The engineers liken their work to that of "neurology" in surgery, emphasizing the meticulous nature of debugging, which cannot be rushed or compromised [10]. - The successful execution of the joint debugging and testing process lays a solid foundation for the empty test run, ensuring that every aspect of train operation is reliable and safe for passengers [10].