Every other exploration was about landing hits. This one is about surviving them. Damage in the arena is not one number against one health bar, it is a hit that lands somewhere, and where it lands changes everything.
First, how much you can take. A bot's health is simply two HP for every kilogram it weighs (floored at 60, capped at 300). A heavyweight is not just harder to push and harder to flip, it has a bigger health bar too:
To keep fights from ending in two seconds, the arena scales all damage down to 45% before anything else. A "20" hit is really a 9. (You saw the same 0.45 in the ram and weapon explorations.)
This is the heart of it. A hit strikes whatever part is closest, and that part soaks a share before the rest leaks to your chassis health:
So the same hit can cost you a sliver or the whole thing, depending only on what it touches. An exposed chassis panel is a death sentence; a slab of armor over it is the difference between a long fight and a short one.
Armor does not just deflect, it also has the most health of any part, 10 HP per kilogram (a wheel is 5, an actuator 8). It is built to be chewed on. And because armor is weight, bolting it on also raises your own health bar. It pays twice.
The catch, of course, is weight. Armor makes you slower to accelerate and easier to out-maneuver (that is the drivetrain side, over in Gear Ratios). Defense is never free.
| Real physics | In BotForge / RumbleBots |
|---|---|
| bigger things take more to destroy | max health = clamp(weight × 2, 60, 300) |
| fights are tuned to last | all damage × 0.45 before it is applied |
| armor absorbs a blow | a hit on armor: chassis takes 15%, the plate eats 85% |
| a hit on a moving part can break it | a hit on a wheel: chassis takes 30%, the wheel eats 70% and can be destroyed |
| armor is heavy but tough | armor HP = weight × 10 (wheel 5, actuator 8) |
Six quick questions. Pick an answer to see why.
For teachers Physics, science and engineering, middle school through high school
Your health scales with weight, and a hit only counts for what reaches the chassis. Armor soaks most of it, a wheel eats some but can break, and a bare panel takes the full blow. Bolt on plate and watch your bot survive twice as long.
In class: Where a hit lands decides how much gets through: armor, a wheel or a bare panel. Students add plate and compare how long the bot survives.
Students need no account and nothing to install, so it works on Chromebooks and as a sub plan.
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