Chapter 9 — Wind Village Robot Team

The TV repairman at the end of the market lifted a heavy CRT TV case out of the pile of liquidation goods at the back of the store, and slammed it down in front of Gia Han, causing a cloud of dust to fly, causing her to step back and avoid it. "You can take whatever you can get in here, I'm planning on selling it for scrap metal this weekend."

Gia Han knelt down and removed each screw holding the back cover with a screwdriver borrowed from Phong, carefully as if dissecting a strange creature. Inside, in addition to the broken and unusable circuitry, she found exactly what Khanh Dan told her to look for: two long aluminum bars running along the screen frame, used to hold the electron beam tube in place - straight, strong, light, exactly the kind of thing that could be cut out to make a pick-up arm.

"Is this okay?" She excitedly called Khanh Dan over to watch, her hands were still covered in black coal dust from inside the TV case.

"Very well." Khanh Dan nodded, picked up the aluminum bar to test its hardness by gently bending both ends. "Exactly what you were looking for to make a gripper frame."

Before that, at the commune health station, they encountered a small obstacle that forced Khanh Dan to learn another lesson about how to ask for things in an unfamiliar place. The nurse on duty initially refused outright, saying that the broken blood pressure measuring device had to be kept until liquidation according to the station's procedures, and could not be taken away arbitrarily, even if it was just scrap. Khanh Dan was about to give up and turn around to find another place, but Gia Han pulled her sleeve back and whispered in her ear, "Let me try."

Gia Han walked to the duty desk, did not immediately ask for things, but asked the nurse about the use of the old blood pressure monitor, asked why it was broken, and asked about technical details that surprised the nurse that a middle school student was so interested. After ten minutes of chatting, when the nurse was completely comfortable, she was the one who proactively suggested: "Let me ask the station chief, it should be okay, you're so eager to learn." Khanh Dan stood looking at that scene, silently remembering one thing: sometimes the most effective way to persuade is not to present your reasons, but to show genuine concern for the person who holds what you need.

On Saturday morning, the whole team divided into two groups and spread out throughout the commune as planned. Gia Han and Khanh Dan walked towards the market, stopping by a TV repair shop, a grocery store with an old backup charger that customers had forgotten and couldn't get back, and a commune health station where there were several broken electronic blood pressure measuring devices that had long since been liquidated. Phong and Nam headed towards the farther hamlets along the foot of Gio Long Pass, while Uyen Nhi followed them, holding a notebook to record each item they found with small drawings so that it would be easier to remember its uses later.

At noon, the whole team met again at the school yard to summarize the results. Nam and Phong returned with a heavy bag, inside were all sorts of things: three power banks burned out but the 18650 battery inside was still usable after checking with a meter, an old monolithic printer obtained from the commune's cultural house that was cleaning out the warehouse, two intact gear reduction motors removed from there, and a handful of screws of all sizes picked up from all sorts of places.

"This is the best one." Nam said, his voice full of pride, pulling out from the bottom of the sack a square plastic box, inside were four tiny servo motors with the original label still intact. "It's a broken wing of a toy model airplane. Uncle Tam's house in the upper neighborhood has left it in the corner of the yard since last year's Tet. I asked for it again, but he gave it to me for free, and even told me to clean up the vacant land."

Khanh Dan picked up the servo box and couldn't hide her surprise. "Four SG90 servos still intact like this, if bought new it would cost more than a hundred thousand each. I found all four at the same time, very lucky."

"It's not luck, miss." Phong said, his voice serious. "We went from house to house since morning, asking if anyone had broken children's toys, if anyone had old unused machinery. No one just gave it to us, we had to ask the right person, at the right place."

Uyen Nhi opened the notebook, pointed to a page full of tiny letters and illustrations of each item, clearly stating whose house she got it from and on what date, so it's easy to come back to thank her or ask for more if needed. "I've written it all down, in case you need to know more later, you can ask."

Khanh Dan looked at the notebook and thought to herself that it was exactly the kind of document that a professional technical team would call a "supply diary" — except that she had never seen anyone do it as devotedly and meticulously as a thirteen-year-old girl biting her lip trying to spell each name correctly.

In the afternoon, when everyone was focused on sorting the pile of items collected outside the school yard, an old man rode by on a bicycle and stopped to look at the pile of components scattered on a tarpaulin on the ground. That is Mr. Sau, who has the largest windmill in the commune, built right at the top of the slope leading to the terraced fields.

"What are you guys doing, selling junk?" He asked, his voice joking but his eyes full of curiosity.

"No, we make robots." Phong replied, not hiding his pride. "I'm looking for a motor with a belt to use as a gripper. If you have something old you can't use, please give it to me."

Mr. Sau nodded, got out of the car, leaned against the tree, sat down next to the tarp and looked closely at the pile of things. "My windmill also uses belts, cut from old bicycle inner tubes. You know, the windmill my grandfather made was from the generation he left behind the recipe, but each generation has modified it a little bit to make it better. Now you guys are making this machine, isn't it the same, just a machine that can listen to commands?"

"You're right." Khanh Dan interjected, smiling. "We're trying to do the same thing he did when he built the windmill — using things we have on hand, gradually modifying them until they run well."

"Then let me go and look in the warehouse to see if there is an old sewing machine motor. In the past, my grandmother used to sew, but now the machine is broken and the motor is still good, maybe it can be used." Mr. Sau said, stood up, brushed off his pants, drove the car forward, and looked back to tell him to follow. "If you can do it, let me see it. I'm very curious."

By the end of the day, when the sun had disappeared behind the western mountains, the tarp spread on the schoolyard was filled with a mixed but valuable pile: more than a dozen motors of all kinds, three coils of wire, two old circuit boards removed from broken TVs that could be used for separate parts, a bunch of screws sorted by size thanks to Uyen Nhi's hard work all afternoon, and four 18650 batteries whose voltage was checked by Gia Han for good condition using a multimeter borrowed from teacher Toan.

"With this, can we start designing real robots?" Gia Han asked, her eyes lit up when looking at the pile of components.

Khanh Dan looked around, calculating in her head what was missing — no ultrasonic sensors, no Arduino boards in sufficient quantity, no off-road wheels suitable for the trail challenge she envisioned in her mind. But looking at the four children squatting around the tarpaulin, their faces smeared with road dust after a day of walking around the commune, their eyes still shining with tireless excitement, she understood that the most important thing they had just collected was not in that pile of scrap metal.

"Almost there." she said. "There are still a few things missing, so I guess I'll have to go to the district to find more. But today, you guys were able to contribute all those things yourself without spending a penny, which is the most important first step."

Nam sat down next to the pile of motors, picked one up and rotated it in his hand, his eyes thoughtful as if imagining what part of the future robot it would become. "So we can really do it? We're not just saying it for fun, are we?"

"Don't say it for fun." Khanh Dan replied, looking straight at him. "From now on, every screw on this canvas will have its place in our first robot."

It was getting dark, the whole team packed the components into cardboard boxes, carried them to the warehouse behind the kitchen for temporary storage, and locked the door carefully. On the way home, Khanh Dan passed Mr. Sau's windmill and saw the blades still spinning steadily in the pale sunset, the creaking sound of the wooden shaft mixed with the sound of the wind whistling through the ravine. She stopped for a moment, looked at the long shadow of the mill on the field, then took out her phone, took a photo and sent it to Hanh with a short text: "Today the whole team went begging for things all over the commune, and came back with a bunch of treasures without spending any money. I think I just understood why the people here are so good at making windmills - not because they have a lot of things, but because they never throw anything away before they are sure it is truly useless."

She put her phone in her pocket and continued walking on the red dirt road that was gradually sinking into darkness, in her mind she had begun to sketch the first robot frame diagram - not on paper, but right while taking each step, amidst the sound of the wind and the creaking sound of the mill still spinning behind her.