Doomsday Mechanic: My Train Can Be Modified Infinitely

Wang Zhengyang moved his left shoulder; the bandage stretched slightly with the contraction of his deltoid muscle, but remained firmly in place, without any loosening or pressure. "Very well done," he commented, his voice still devoid of emotion. "Now, back to your workstation. By four o'clock this afternoon, I want to see the preliminary technical framework and component selection list for the simplified design of the shield system."

"Yes!" Lin Luo'er sat back down at the workbench and opened the circuit design software, but the blush on her cheeks had not completely faded, and the tips of her ears were still pink.

Wang Zhengyang began organizing the newly imported technical files, categorizing and archiving them according to implementation difficulty, resource requirements, and time priority. The only sounds in the carriage were the tapping of keyboards, the low hum of computer cooling fans, and the rhythmic breathing of the two men.

About thirty minutes later, Lin Luo'er suddenly spoke softly, her eyes still fixed on the simulated waveform on the screen: "Engineer Wang..."

"explain."

"Um... if you get injured while on a mission in the future... you can come back to me for treatment." Her voice grew softer and softer, as if afraid of disturbing the air. "My battlefield first aid skills... although I haven't used them on real wounded people, my simulation test scores are all excellent... so they should be reliable."

Wang Zhengyang's fingers paused in mid-air for about 0.5 seconds as he typed on the keyboard.

Rational analysis: Having a member with professional-level first aid skills who is willing to proactively take on this responsibility is an optimal allocation of human resources, significantly improving the overall survival rate and mission endurance. On an emotional level… the care and commitment implied in this statement, as well as the subtle psychology of “wanting to be needed,” clearly transcends the realm of a purely working relationship.

Without turning around, his gaze remained fixed on the scrolling technical parameters and bill of materials on the screen, and he calmly replied, "Understood. Now, focus on the resonant design on your screen. The damping coefficient of the second-stage filter needs adjustment; the model you're using may experience self-excited oscillations under high-power transients."

"...Oh." Lin Luo'er responded, a hint of disappointment in her voice, but she was immediately drawn back to the technical problem and returned to her work. "Self-excited oscillation...I'll run the transient simulation again..."

Wang Zhengyang continued working, but out of the corner of his eye, he noticed that Lin Luoer had secretly glanced at him five times in the next hour.

The first time, she worried about whether the wound had been properly treated, her gaze lingering on the bandage for three seconds. The second time, to confirm if he was focused on his work, she quickly scanned his profile. The third time, her gaze lingered a little longer, tracing the lines of his fingers typing on the keyboard and the focused contours of his face. The fourth time… she seemed to want to say something, her lips moved, but she ultimately lowered her head. The fifth time, she “accidentally” poured an extra glass of water, gently pushing it towards him before quickly returning to her seat, her earlobes flushing again.

Outside the window, the eastern sky began to lighten with the first hint of dawn, the edge of the deep blue night sky tinged with a pale blue, which then gradually melted into orange-red. The morning light was about to pierce the mist over Berlin.

Wang Zhengyang closed a running file analysis program and mentally updated today's work list and personnel status assessment. Lin Luoer's performance met expectations—solid professional skills, quick learning speed, and a tendency to proactively take responsibility and care about the team. As for those subtle emotional fluctuations… as long as they don't affect core work efficiency and decision-making objectivity, they can be included in the observation scope for now, without needing to actively intervene or reinforce them.

He stood up and walked to the carriage window. Morning mist was slowly rising above the marshalling yard, like the breath of the earth. The massive "Longyuan" train was faintly visible in the mist, its black steel outline resembling a slumbering ancient creature. In twenty days, this train would need to complete basic body reinforcement, upgrade its running gear, and reconstruct its internal functional zones, acquiring preliminary off-road mobility and basic protection.

But what he needs to do goes far beyond that.

The morning light pierced the thin mist outside Berlin, illuminating the rusty rails and the silent train frames at the marshalling yard. Wang Zhengyang stood at the very front of the Longyuan locomotive, his dark gray overalls sleeves rolled up to his elbows, revealing the muscular lines of his forearms. Behind him, Lin Luoer, Chen Yishang, Li Zhenhua, Zhang Haitao, Liu Qiming, and Wang Jianguo were all present, a dozen pairs of eyes focused on the exposed steel viscera of the massive MTU diesel engine.

"From today onwards, the core task for the next seven days is to complete the basic structural modification of the Longyuan." Wang Zhengyang's voice wasn't loud, but it carried a metallic penetrating force, echoing clearly across the empty platform. He didn't turn around, his gaze sweeping over every inch of the front of the vehicle like a measuring instrument. "The focus is on three aspects: reinforcing the armor of key areas of the hull, comprehensively upgrading the running gear, and reconstructing the functional zoning of the interior space. This isn't ordinary maintenance; it's a structural transformation."

He raised his arm, his fingertips pointing towards the locomotive's cab area. "First section, the locomotive. We'll retain the original MTU 12V 4000 R43 diesel engine as the main propulsion system—this machine has proven its stable output, fuel efficiency, and reliability over decades, and it's the cornerstone of our power system. However, the original engine's electronic and hydraulic systems are too fragile, a fatal weakness."

Chen Yishang had already opened his waterproof notebook, pen nib hovering over the paper. The former railway engineer's sharp eyes caught every technical detail in Wang Zhengyang's words.

"So the first item," Wang Zhengyang turned to him, "is to add a second, completely independent set of electrical and hydraulic control circuits without altering the core mechanical structure. Requirements: the circuits must be physically isolated from the original system, the wiring conduits must be laid independently, and the control terminals must be set up independently. The ultimate goal is to achieve redundancy and mutual backup between the locomotive's head and the third rear car's power units."

He pulled up a 3D diagram on his tablet, projecting the image onto a temporary display screen next to him. The complex circuit diagram resembled a neural network, with red representing the original system and blue representing newly added redundant lines. They clearly intersected yet remained strictly separated in the equipment compartment behind the driver's cab.

"When the vehicle's power system malfunctions, the redundant system must be able to automatically detect and switch to the rear vehicle's power unit for control within 2 seconds; and vice versa." Wang Zhengyang zoomed in on the details of the switching mechanism, "This means you need to design a triple-verified switching logic: main system status monitoring, backup system readiness confirmation, and switching command execution and feedback. The response time must be controlled within 2 seconds—this is the lifeline."

Chen Yishang's pen began to move rapidly, and notes, a mix of German and Chinese technical terms, quickly took shape. "The isolation standard adopts the DIN EN 50122 standard for high-voltage electrical isolation in rail transit, and opto-isolation modules are installed on the control signal lines. For the switching logic, I suggest using a redundant PLC controller with hard-wired backup, which should be reliable within 2 seconds."

"Okay." Wang Zhengyang nodded, then switched the screen to display a diagram of the driver's cab. "Next is the reinforcement of protection. This is the key point."