Chapter 21 — Wind Village Robot Team

The morning started with the whole team watching the Kim Long team compete first. The order of the competition was randomly drawn and station 12 fell into the third round in the list of more than thirty teams. Trinh Anh Khoa's robot rolled smoothly on the track, handling all challenges at a speed nearly twice as fast as what the Gio Nui team had ever achieved in practice. The CNC metal handle operated so precisely that it did not drop a single block of wood, completing the entire challenge in just one minute and forty seconds, achieving a perfect score.

Applause echoed throughout the arena as the scoreboard appeared. Nam stood silently watching, unable to hide his shock. "Twice as fast as me." He muttered.

"They have CNC machines, and they have engineers instructing them twice a week throughout the year." Khanh Dan said, her voice calm. "I can't compare my speed with them. I can only compare myself with myself last week."

No one responded, but the whole group silently nodded, and when their team's name was announced immediately, they all put the image of the shiny robot out of their minds and focused entirely on their own competition.

"Mountain Wind Team, Long Phong Secondary School, please prepare to take position." The loudspeaker's voice echoed throughout the arena, the sound reverberating from the high dome made it feel like the call was many times louder than it actually was.

Khanh Dan's heart beat as fast as the four students standing next to him. Gia Han held the laptop controller close to her chest, her hands shaking slightly as she retyped the boot code one last time. Phong stood next to the robot, one hand placed on the chassis as if reassuring itself. Nam stood straight, both hands clenched, and Uyen Nhi held a small board ready to write down the main bullet points for the introduction, even though she had memorized most of it.

"Our team has three minutes of introduction first, then comes the competition." Khanh Dan repeated it one last time, even though the whole team had heard this sentence no less than ten times that morning. "Uyen Nhi presented the introduction and the idea of "Wind Eyes", Gia Han talked about the programming techniques. Remember, it doesn't need to be perfect, just real."

The group walked out to the main competition area amidst the gazes of dozens of onlookers standing around the safety fence, including other teams who took advantage of the break to watch their opponents. The jury sat in a row in front, five people, among whom Khanh Dan recognized the man wearing the "Technical Advisor" badge she had seen passing by the previous afternoon, now sitting in the center, holding a pen and tapping lightly on the table.

Uyen Nhi stepped up, took a deep breath, her voice rang out through the handheld microphone, shaking slightly at the first sentence but quickly stabilizing.

"Dear judges, we come from Long Phong Secondary School, a mountainous commune where the internet only reaches the top of the hill, and our laboratory is an old warehouse behind the boarding kitchen." She spoke, her voice still shaking but clear, pointing to the "Wind Eyes" illustration board hanging next to the table. "Our robot is called Gio Nui, and its most special part, we call Gio's Eye — a homemade color sensor from a broken LED light and a photoresist removed from an old sensor light, because we don't have money to buy a specialized color sensor."

A few judges looked at each other, seemingly surprised by the straightforward opening, which was different from the usual flashy introductions. The man wearing the technical advisor badge stopped tapping his pen and listened more attentively.

Gia Han continued, briefly explaining the control code and how the robot processes signals from three sensors at the same time. Her voice was confident and clear, without stumbling over a single word - the result of countless evenings of practice with Uyen Nhi in the warehouse.

Coming to the official competition, Phong placed the robot on the starting line, Nam stood next to check the connections one last time, and Gia Han sat in the remote control position via laptop, her finger placed on the Enter key.

"Three, two, one, start!" The referee shouted loudly and pressed the timer.

The Mountain Wind Robot rolls and passes the steep slope smoothly thanks to countless practice sessions on the inclined plank in the warehouse. Coming to the Z-turn, the robot slowed down exactly as programmed, neatly handling both corners in a row without derailing, causing a few sporadic applause to ring out from the audience.

Coming to the gravel section - where yesterday the robot slipped slightly - Gia Han held her breath and looked at the screen, but this time, thanks to the sensor parameters that were calibrated last night, the robot passed stably, only shaking slightly and then continuing straight to the object picking area.

This is the hardest part. The pick-up arm reaches out, "Wind Eye" scans the first wooden block - red - accurately identifies it, picks it up gently thanks to the force feedback mechanism that Nam and Phong have painstakingly edited, and drops it correctly into the red basket. The applause grew louder.

The second block, green, is handled equally smoothly.

When it came to the third, yellow block - the most difficult part to identify because it required comparing two nearly equal values - the grabber reached out, "Wind Eyes" took a little longer to process than usual, making the whole team hold their breath. Finally, the correct identification light turns yellow, the gripper closes, lifting the wooden block.

But as soon as the picker moved to the gold basket, a slight vibration from the robot's own movement caused the wooden block to slip out of the picker's hand, fall to the floor just a few centimeters away from the basket, and roll outside the designated area.

A small "oh" rang out from the audience. Gia Han pursed her lips, but there was nothing to do now but let the robot continue rolling to the finish line, completing the rest of the challenge within the allotted time.

"Time's up!" The referee shouted, the clock stopped at two minutes and forty seconds, there were twenty seconds remaining that the team did not need to use.

The electronic scoreboard appeared: two correct blocks, twenty points each, forty points total, plus points for completing the terrain. Not the highest score of the day, but enough to enter the top twelve teams with the best qualifying scores, the teams that will qualify for the final round tomorrow.

The whole team hugged each other as soon as they knew the results, cheers mixed with the applause of the surrounding audience. Uyen Nhi jumped up and down, there was no trace of the trembling girl standing in front of the microphone just a few minutes ago. Nam punched his fist in the air and shouted loudly without words.

"I'm in the finals!" Phong shouted, hugging the robot tightly as if it had just saved his whole family.

Khanh Dan stood watching all four students celebrate, feeling an indescribable joy rising in her chest, but at the same time, she also glanced at the yellow block of wood still lying outside the sorting basket area, reminding herself that tomorrow, in the final round, they would not have much room for a similar mistake.

"I'm happy, but tonight I have to review the code to pick up the gold block." She said, her voice still filled with excitement but not forgetting her mission. "Tomorrow the pressure will be much greater."

Gia Han nodded, although the smile had not yet disappeared from her lips. "I know, miss. But let us celebrate for five more minutes, okay?"

Khanh Dan laughed, nodded, and let the team's joy last a little longer before returning to their unfinished business — a job that none of them knew would turn out to be much more serious than a block of wood falling from the handle.

That night, returning to the room, Gia Han and Nam sat with the robot until nearly eleven o'clock at night, removing the gripper and carefully checking each joint. Nam discovered that a screw at the wrist joint was slightly loose, perhaps due to vibrations while being transported from Long Phong down here, causing the accuracy when holding the object to decrease at the most critical moment.

"Tighten it and it'll be fine." Nam said, tightened the screw with the same screwdriver set that Mr. Tu gave Phong, tried opening and closing the handle a few times, feeling the solidity had returned. "Tomorrow I'm sure we won't make this mistake again."

Gia Han nodded, but still carefully wrote another note in the technical notebook she brought along: "Recheck all screws before each test, especially after transportation." She closed the notebook, looked at the robot lying quietly on the table under the light of the break room, and softly sighed in relief.

"Tomorrow is the final." She said, half reminding Nam, half reminding herself.

"Tomorrow is the final." Nam repeated, put the gripper back in the right position, tightened it one last time, his eyes looked at the robot with a trust that was completely different from the first evening when he tremblingly plugged in the battery wire and burned the first chip not long ago.

They put the robot back in the cardboard box, this time lining it with a spare layer of dry rice husks, carefully closing the lid, then turning off the lights and going to sleep. No one in the room knew that, at that moment, below the hotel floor, a sudden storm was forming offshore, and that come the next morning, it would bring a challenge far greater than anything they had ever prepared for.