EV3 Robotics›Level 4 · WRO Prep›Lesson 46
Level 4 · Lesson 46 · EV3-L04-4660 minutes · Block 6 of 6 · Mat: WRO 2026 — Robot Rockstars
The complete set, twice — with no fixes in between.
Every mock round so far gave you two minutes and one change between rounds. Today gives you nothing. Both rounds run the same program, the same gains, the same robot.
That fix window has been carrying you. It lets a robot that is not quite finished look finished, because round two is always allowed to be the repaired version. Take it away and the question becomes the real one: is this robot done?
If round two collapses without the fix, that is worth knowing now. There are two lessons left to act on it, and neither of them is a good place to find out.
Everything is live: the concert stage at A, the tour trucks at B, the café at C, the park strip at D, and the main plaza at E, from HOME in the bottom-left corner and back to it.
Run the route you costed in lesson 41 — the one that fits — not the one you wish fitted. Improvising an extra station mid-round usually loses the ones you had.
Have your abandon points to hand from lesson 45: for each mission, where the robot can be left and still reach the next one. Today is the first time those matter under a clock.
This is the first run with all of it together, and that is the interesting part. Individually every piece works. Today finds out whether they work in the same program.
Expect the interactions to break, not the parts. A recovery that fires and leaves the gyro heading wrong. A log that fills differently when a mission is abandoned. A menu choice that runs a mission whose mechanism moved to the other Brick. Nothing on that list is a bug in one lesson’s work — they are all bugs between two.
Full competition standard, and this block adds two items to the list:
The observer’s job is specific: for every failure, record where on the mat and which kind — lost line, stall, frozen sensor, chain, or none of those. “It went wrong at the plaza” is not a diagnosis.
The program is finished and today it stays finished. Use this time to check rather than change.
Whatever you find now, fix now. Once round one starts, the program is sealed until the end of the lesson — including between the rounds. That is the whole point of today.
Between the rounds you will want to change something. Do not. Instead write it down.
What you would change, and why, decided while watching round one, before round two runs.
Then run round two, and afterwards compare that note against what actually mattered.
That comparison is the most useful thing in this lesson. Teams routinely want to change the most dramatic failure rather than the most expensive one. A note written before round two, checked against round two, tells you whether your instinct under pressure is any good — and that instinct is what you will be relying on in lesson 48.
After both rounds, make the change and run once more, unscored, to see whether it helped. That run is not part of the rehearsal; it is preparation for the scrimmage.
Round one is cold. No practice lap, no warm-up. Place by the ritual, power up the chain in the written order, calibrate, choose from the menu, read the selection back, start, hands off. Score it and time it.
Round two follows immediately. Nothing touched. Same program, same gains, same robot. Score it and time it.
Then read the robot’s own summary off the screen after each and compare against the scorer’s sheet before the mat is cleared.
Compare the two rounds against each other. Two similar scores means a robot you can rely on. A good round one and a bad round two means something is not repeatable — and finding out which, with two lessons left, is exactly what today was for.
Today’s entry, and lesson 48’s judge will read it:
Tomorrow somebody else judges you. The scrimmage scores the run and the documentation together, and a judge will ask why you built what you built. The answers are in the journal you have been keeping since lesson 41 — start reading it back tonight.
This model drives, so its challenges are run on a mat. Mats differ between branches — check you are looking at the one in your room.
WRO 2026 RoboMission Elementary — Robot Rockstars · official WRO game mat, 2362 × 1143 mm
The challenges name these places rather than distances, so the same challenge works on any mat:
Switch mats above and every route below is redrawn on the mat you chose.
Work through the challenges in order — each is harder than the last. The mission comes after all three, and it is meant to make you plan before you build.
Set the mat to competition standard — flat, taped, level table, lighting as on the day, ALL Bricks charged, modules and configuration cards on the table, setup ritual written out including the chain power-up order. Then run round one cold, scored and timed, with an observer recording where and which KIND for every failure: lost line, stall, frozen sensor, chain, or none of those.
Run round two immediately with NOTHING touched. No two minutes, no one change — same program, same gains, same robot. That fix window has been quietly carrying you since lesson 8, because round two was always allowed to be the repaired version. Without it the question becomes the real one: is this robot done?
Write down the change you WOULD have made, decided while watching round one and before round two runs, then compare it afterwards against what actually mattered. Teams reliably want to change the most dramatic failure rather than the most expensive one, and this tells you whether your instinct under pressure is any good.
Run the complete 2026 set twice under competition conditions with no fixes between, then compare the two rounds against each other. Two similar scores means a robot you can rely on; a good round one and a bad round two means something is not repeatable, and finding out which with two lessons left is exactly what today was for. Expect the INTERACTIONS between Blocks 4, 5 and 6 to break rather than any one part.