Saki: glasses version.
Jin instructed Reiko to finish boiling down the remaining sap until it all became maple syrup.
Now that Saki had regained her composure, they decided to start their discussion over.
"Hmm, I really can't let Saki continue like this..." Reinhard said with a grim expression. As her childhood friend, he was clearly concerned.
"By the way, why did your servants leave?" Jin asked.
Saki scratched her head and gave a wry smile as she explained the reason. "Well, I hadn't paid them for three months."
"That’s just asking for trouble..." Jin couldn't help but retort.
"For the time being, perhaps I should have meals delivered from my house," Reinhard suggested, deep in thought.
"Unpaid wages for three months? What on earth happened? You have quite a lot of expensive materials here... Don't tell me?"
"Kufufu, it’s probably exactly what you’re thinking. If my father sees a rare material, he buys it regardless of the cost. Well, I’m the same way."
In short, she was a research nut with zero sense of economics.
"You should hire a steward to manage things properly," Reinhard said, exasperated.
Saki remained unperturbed. "We aren’t nobles. We don’t need a steward or a butler."
"But still..."
While Saki treated the matter as if it were someone else's problem and Reinhard fretted, Jin came up with a plan.
"I know. Reinhard, why don't you build her an Automata?"
Reinhard jumped at the suggestion, his engineering-obsessed nature on full display. "Oh! There’s an idea! Of course, you’ll help me, won't you, Jin?"
"Of course."
At Jin's confirmation, Reinhard’s excitement soared. "Alright! In that case, let’s build the world's second-best Automata!"
Watching the high-spirited Reinhard, Saki voiced a question. "...Not that it matters, but what's with this 'world's second-best' business?"
"Hmm? That's simple. Because the world's best Automata is Reiko-chan right there."
Reminded of Reiko, Saki stared intently at her through her new glasses. "The more I look, the more magnificent her craftsmanship is... That reminds me. Reinhard, Jin. It’s truly a stroke of luck to have two of the world’s top magi engineers gathered here."
Saki leaned forward across the table.
"Hmm? Is there something you want to ask?" Reinhard said lightheartedly.
Alchemy and magi-engineering shared commonalities, and both fields had developed by influencing each other. Reinhard assumed she had a technical question, never dreaming he would find himself unable to answer what came out of Saki’s mouth next.
"Tell me, then: how can magi-dolls like Golems and Automata hold something as fragile as a cup without breaking it?"
"...Ugh." Reinhard froze.
The basic movement controls for Golems and Automata were usually passed down from a master to their apprentice. That master had received it from their own, and so on.
One could compare this control method to an operating system. Typical magi engineers inherited it as a "black box" from their teachers and used it without understanding the underlying mechanics. There was no progress to be found there.
If one traced the origins, most current control methods would likely lead back to Adriana Barbora Tsetse. Furthermore, the details of these control methods were recorded in the "library" of this magic-filled world, much like magic itself. The reality was that most magi engineers simply accessed the library and copied the code.
As for Jin:
"...Well, it’s quite complex, so I’ll give you a simplified explanation. First, the unit recognizes the object. It compares that object with its own knowledge, and if there’s a match, it grasps it with an amount of force appropriate for that object's strength."
Jin explained the flow in simple terms. Not only Saki, but Reinhard as well, listened with admiration.
While Reinhard sat there ruminating on the explanation, Saki posed a follow-up.
"Hmm, interesting... But what if it’s an object not found in its knowledge? If it’s something seen for the first time, the unit wouldn't know its strength, right?"
"You certainly don't hold back with the difficult questions... Up to the point of recognition, it’s the same. If the object isn't in its knowledge base, the unit performs an 'analogy.' It looks for something similar in shape or material."
"I see. That makes perfect sense."
Jin gave a knowing grin as Saki nodded. "It’s fine as long as there’s something similar. But you want to know what happens when there isn’t, right?"
"Kufufu, exactly."
"I thought so... It starts the action of grasping. The fingers touch the object. It begins to apply force... You follow me so far?"
"Yes, of course. The problem is what comes next. If it applies too much force, it breaks the object. If there isn't enough, it can't hold it. What does it do then?"
"It detects the deformation of the object and its own fingertips."
"Eh?...Is that true, Jin?" It was Reinhard who spoke up. He looked as if he was hearing this for the very first time.
"The control core issues commands while predicting what the body's shape should be. The physical body moves with a tiny delay—a few hundredths of a second—behind those commands."
"............"
Saki and Reinhard listened in silence as Jin continued.
"When the fingers touch an object, the speed of the fingers' movement slows down relative to the object's hardness. If it's soft, the movement doesn't slow down as much; if it's hard, it slows down immediately. By quickly detecting this difference, the core determines the necessary force."
Jin added a further supplement.
"By the way, it does make mistakes sometimes. Even humans drop things that are heavier than they look. But since a core's reaction speed is dozens of times faster than a human's, it can usually compensate in time."
Having finished his explanation, Jin looked between the two.
Reinhard, ever the magi engineer, was trying to digest the information as technical knowledge. Saki, on the other hand, seemed satisfied just knowing the conceptual "why."
"Wow, Jin, thank you! One of my long-standing mysteries has been solved!" she exclaimed with great joy. "And I'm correct in assuming this is only possible because the control core can think dozens of times faster than a human, right?"
"Yeah, that's right." Jin nodded at Saki's clarifying question.
"Then that means the control core is performing an incredibly difficult task—constantly predicting what the body's shape should be."
"Exactly... Wait."
Jin paused to reconsider Saki's point. In engineering, the principle of "simple is best" usually held true, especially for systems.
"Jin? Is something wrong?"
Saki called out, confused by his sudden silence, but her voice didn't reach him.
(The act of adjusting force consumes a massive amount of the control core's processing power. In other words, the entire burden is placed on the software...)
Jin wasn't an expert in electronics or IT, but as an engineer who had lived on modern Earth, he was familiar with the concepts.
(Software is versatile, certainly. But if hardware could shoulder that burden, it would reduce the load on the control core and free it up for other processes...)
"Hello? Jin? Earth to Jin!"
Jin was more focused on his thoughts than he had been in a long time.
(Then, what is the hardware equivalent? Automata and Golems were built to mimic the human body. What do humans have that Automata don't?...A sense of touch!)
Sight used the eyes. Hearing, the ears. Smell, the nose. Taste, the mouth. Each of these had dedicated magi-devices that functioned as pseudo-sensory organs.
But touch was dreadfully neglected.
For heat and cold, a magi-device serving as a temperature sensor was located in the chest to monitor the temperature of the metal skeleton. It was merely a secondary feature of the device that regulated body heat. If used skillfully, it could detect the temperature of something touched by the fingertips.
Pain was never even considered from the start.
(A while back, I speculated that Reiko doesn't use the sword techniques she learns because delicate force adjustment is too difficult for her.)
Complex movements required subtle control. No matter how much faster a core’s processing power was compared to a human's, adjusting force while moving at dozens or hundreds of times a human's speed was an extreme challenge.
Furthermore, Reiko's power was immense. The difficulty of adjusting a force of 10 down to 1 compared to adjusting 10,000 down to 1 was, quite literally, orders of magnitude higher.
Which was harder to control: simple actions like punching and kicking, or complex actions like joint locks? The answer was obvious upon reflection. He and Laojun had reached that very conclusion during their previous consultation.
(Ah... I see...)
He now saw a path to letting Reiko recognize force adjustments more accurately.
(I hadn't analyzed it deeply enough...)
To adjust her strength, Reiko had to finely control the output of her ether converter and mana driver, and then manipulate her magical muscle with micron-level precision—all while moving at speeds far beyond human capability.
Reiko herself likely hadn't been able to explain to Jin why it was so difficult.
"...What's the matter with Jin?"
"He’s probably realized something important."
Several minutes had passed since Jin had retreated into his thoughts. Saki and Reinhard were whispering to each other.
"Kufufu, Reinhard used to get like that sometimes too. I suppose you'd call him a technical nerd."
"I don't want to hear that from you, Saki."
Jin finally returned to reality.
"Saki, thank you! Because of what you said, I think I can make a major breakthrough!"
As Jin shouted his thanks, Saki replied with a look of bewilderment.
"Kufufu, I don't quite understand, but I'm honored to have been of help. If you don't mind, could you explain it so we can understand too?"
"Yeah, of course! Reinhard, I want to hear your opinion on this as well."
With that, Jin began to explain the control theory he had just conceptualized.