Chapter 228: Chapter 224: Creating a Shield Tunneling Machine Model
"The cutterhead can be improvised with existing materials, and both the steam engine and turbine can be used for the power system. That’s not a problem." Perfikot looked at the preliminary drawing and suddenly felt conflicted.
She bit into the second knuckle of her right index finger in deep thought because she had discovered a very fatal problem.
The issue was that the structure and working principle of the shield machine determined that it was a straight cylinder. Although structural adjustments could make it bend, making it dig out a spiral tunnel underground was still no easy task.
At least for Perfikot, there were just too many improvements needed on the blueprint.
The main part of the shield machine could be made into a curved pipe, and the drive shaft for transmitting power forward would need a universal joint installed. These were within the scope she could easily solve.
But how to make the shield machine advance in a spiral trajectory as planned was what made Perfikot feel troubled.
She needed to dig a spiral tunnel, and modifying the shield machine body into a curved tube was easy to understand and solve.
However, there was a critical part in the shield machine’s structure, which was the propulsion device used to push the shield machine forward.
This device is usually driven by hydraulic mechanisms, and pushing straight forward is simple; just all the hydraulic devices push together.
But spiral turning propulsion wasn’t a simple matter.
Even shield machines of later generations didn’t easily solve this problem, but they had computers and automated control systems, making it relatively less difficult to achieve.
Moreover, most tunnels using shield machines in later generations were straight, and even if there were turns, the degree of turn was not large. As long as the direction the cutterhead traveled was controlled, and the shield machine body turned accurately, it wasn’t a big issue.
After all, with computer control, more complex maneuvers could be done; let alone just having a shield machine turn.
However, Perfikot needed to construct a spiral-structured tunnel, which required her designed shield machine to advance in a spiral, meaning it constantly needed to turn.
This necessitated that the thrust direction applied by the propulsion mechanism when pushing forward was not in a straight line but a force causing the cutterhead in front to turn.
This required a quite complex propulsion structure and also needed special designs for the shield machine’s main body.
Since it was a spiral advance, the distance advanced on the outer edge was undoubtedly greater than the inner side, which Perfikot could solve with hydraulic cylinders of different lengths. Although the structure was more complicated, and control more cumbersome, it wasn’t impossible.
But advancing the main structure left Perfikot scratching her head since, besides controlling the cutterhead’s advancement and direction, the shield machine’s main body also needed to move forward.
In the original world, a shield machine turning is equivalent to a long and large bus turning on a highway, just directing the front wheels to steer along the road.
While Perfikot’s design of this shield machine was equivalent to a vehicle that itself was curved, constantly circling in place, clearly impossible for a traditional shield machine structure.
"Forget it, better to make a model and test it out than to scratch my head." Perfikot gave up on thinking and ultimately decided to make a model first, then identify problems requiring improvement.
She did the same when working on the Flying Airship, first creating a model and then making improvements based on the model, ultimately finalizing the design.
Moreover, from a certain perspective, if the design was only on paper and not verifiable through actual construction, it was meaningless.
After all, any design has to end up being practical; without being constructed, what significance does a perfect design have?
Therefore, after completing the preliminary design, Perfikot took the blueprints to her lab, laid the drawing out on the test bench, and began making parts.
Since it was just a verification model, the parts were naturally very fine, approximately at a 1:72 scale compared to the real size, a common model scale for Perfikot, with familiar parts dimensions.
"Let’s see, first the shield of the shield machine..." Perfikot had her maid doll fetch materials from the warehouse and then drew an Alchemy Array on the table, before shaping the materials as she wanted.
However, for ease of installing subsequent parts and continually adjusting them, Perfikot did not make the shield of the shield machine model into a complete cylinder, but rather into two separable sections, allowing easy adjustment of the internal structure at any time.
Next was the creation of the steam engine model, which was also a familiar task for Perfikot, having made steam cores for the maid doll, designed the power system for the Flying Airship model, and developed steam turbines. She was already very familiar with the steam engine structure and, with the aid of the Philosopher’s Stone-enhanced alchemy, skilfully produced a miniature steam engine to install into the main structure of the shield machine.
Following that was naturally the cutterhead, but due to its small size, Perfikot did not install blade heads on the cutterhead.
After all, they were so small that installed blade heads wouldn’t even be the size of a grain of rice, lacking practical significance. So, Perfikot just made some protrusions on the cutterhead, representing them as blade heads.
As long as the main structure of the cutterhead wasn’t in question, at this shield machine model’s size, those protrusions on the cutterhead could serve as blade heads.
After completing these major components, Perfikot took a deep breath, looked at the blueprint’s intricate transmission, propulsion, and drive mechanisms, and resignedly began crafting these finely detailed parts.
If it was just a matter of pure machining, these parts, though small, were still manageable for Perfikot.
Her proficiency in alchemy allowed for an extremely fine degree of precision, down to invisible levels. However, aside from construction, assembling these parts was very taxing, as some pieces were so small that some gears were no bigger than a grain of rice. Even an alchemy master like Perfikot needed special magnifying glasses to see these tiny precision parts clearly and then carefully piece them together with tweezers.
After an assembly process so long that it left her feeling stiff and sore, the tiny parts and mechanical structure on this shield machine model were finally complete, prompting Perfikot to stretch her back and beat her aching shoulders and neck.
But fortunately, the model of the shield machine was finally completed.
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