> For the complete documentation index, see [llms.txt](https://docs.revrobotics.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.revrobotics.com/classroom-activities/large-activities/rubble-robots-challenge.md).

# Rubble Robots Challenge

{% hint style="info" %}
This activity is designed to be a skill-building challenge that can be hosted within a single classroom or as a community event! 

A non-competitive version of this challenge is available in Unit 3 of the [Intro to Robotics V2 curriculum](https://www.revrobotics.com/curriculum/).
{% endhint %}

## Activity Description 

In this challenge, teams have been contracted to develop a robot that can help clear rubble from a construction site. This robot will be driven by an operator, but will need to move different kinds of debris to the appropriate area for collection.

Additionally, there are plants and existing structures on the construction site the robot and operator must be careful to not damage or remove.

## Materials

* Non-robotic craft materials for building such as cardboard, construction paper, tape, cups, pipe cleaner, popsicle sticks, straws, etc
* Floor safe tape (ex: painter’s tape) to mark the area
* 3 different “debris” materials for the robots to move 
  * Recommended: tennis ball/other small ball, toilet paper tubes, crumpled paper balls
  * Other options: balls of different color, math or small wooden blocks, cups, small empty boxes, pom-pom balls, old FTC game pieces, small/round fidget toys, empty bottles or cans
* Obstacles for the play area that the robot should avoid
  * Suggested: cones, small boxes, books, cups, potted plants, containers, etc

### Robot Materials

Recommended REV Robotics Kit Options:

* [EDU Kit V2](https://www.revrobotics.com/rev-45-2041/)
* [FTC Starter Kit V3.1](https://www.revrobotics.com/rev-45-3529/)
* [*FIRST* Global Competition Kit](https://docs.revrobotics.com/first-global)

Suggested Starting Robot Drivetrain:

* [Class Bot V2](https://docs.revrobotics.com/duo-build/ftc-starter-kit-class-bot)
* [C-Channel Drivetrain ](https://docs.revrobotics.com/duo-build/channel-drivetrain-build-guide)

## Field Set Up

<figure><img src="https://798570500-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FyVmijj3v4kilmwUNybDv%2Fuploads%2FqUqftGkUzzj6dM1JH2eV%2Fimage.png?alt=media&amp;token=08016169-c367-45e0-9763-4a2df51502b9" alt=""><figcaption><p>Construction Site layout for Rubble Robots</p></figcaption></figure>

Rubble Robots is played on a 2.5m x 2.5m field that can be adjusted to accommodate space limitations. The layout provided is one example for how the Plant or Structure Obstacles may be arranged. If the play space is reduced, the number of obstacles should also be reduced.&#x20;

The outside perimeter of the field should be marked with tape, or another material.&#x20;

<details>

<summary>Example Pictures</summary>

<img src="https://798570500-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FyVmijj3v4kilmwUNybDv%2Fuploads%2FVbhoIxCyGZtRbUNqvTmM%2Funknown.png?alt=media&amp;token=6616b8d1-c6fe-491e-9d2b-40895de66bac" alt="Rubble Robots with small plants as obstacles" height="353" width="567">

<img src="https://798570500-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FyVmijj3v4kilmwUNybDv%2Fuploads%2FTJp0y90KHw6XUidcxGZ8%2Funknown.png?alt=media&amp;token=cd9abc57-fea8-4da7-a1a4-7049dd4d5af7" alt="Rubble Robots with small plants as obstacles" height="395" width="559">

<img src="https://798570500-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FyVmijj3v4kilmwUNybDv%2Fuploads%2FK3zbptHi6ygFM6mVcAQp%2Funknown.png?alt=media&amp;token=91d9251f-5594-4eaa-a283-1201c7c887da" alt="Rubble Robots with TREV plushies as obstacles" height="402" width="624">

</details>

### Field Elements

**Plants or Structures** are obstacles on the field the operator must avoid while controlling the robot to pick up debris. The robot may not displace or damage these obstacles.&#x20;

**Collection Zones** (Trash, Structural, and Environmental) are the drop-off locations for the 3 different types of debris that will be scattered on the field.&#x20;

**Debris** are loose pieces placed randomly on the field before a match for the robot to gather and place into the correct Collection Zone.

* It’s encouraged to use recycled materials for the debris, such as having students bring in the toilet paper rolls or using scrap paper for the crumpled paper balls.
* It’s recommended to start with a set amount of each item then increase or decrease based on student performance.
* Suggested:
  * Trash (orange) = crumpled paper balls (x10)
  * Environmental (red) = toilet paper rolls (x10)
  * Structural (purple) = small ball game piece (x3-x5) such as the Artifact wiffle balls from FTC (2025-26) or Wildfire ball from FGC (2026)

#### Field Set Up Document

{% file src="/files/70icoC0ES5w16Nd1AGhg" %}

## Rubble Robots Rules

### Robot Rules

* [ ] The robot must be drivable using a gamepad
  * [ ] Teams may choose to use two gamepads for split controls.

* [ ] The robot must allow the operator to retrieve and move 3 different forms of debris to their appropriate collection location

* [ ] The robot must fit within a 460mm x 460mm square at start up. There is no max height limit.

* [ ] The robot must complete the clean up in 2 minutes

### Game Rules

#### Basics

* [ ] The robot must remain within the designated play area.
* [ ] The robot may not damage or move existing plants and structures within the construction site
* [ ] Only one robot is permitted in the play area at a time.
* [ ] Teams will have 5 minutes to prepare, run their robot, and attempt the challenge.
  * [ ] The clean up attempt is limited to 2 minutes.

#### Launch Zone

* [ ] The robot must start in the marked “Robot Launch Zone”.
* [ ] The robot is considered “inside” the launch zone so long as some part of the robot is extended into the area
* [ ] Robots may only be handled within the launch zone. Touching a robot outside of this area will result in a penalty.
  * [ ] Students may change out parts or make changes to the robot if it returns to the Robot Launch Zone

#### Debris

* [ ] Robots may not damage (ex: rip, misshape, crack) debris.
* [ ] Debris that leaves the play area will be returned in a random location.
* [ ] Debris that is scored in the incorrect Collection Zone will be removed and cause a penalty.
* [ ] There is no limit to the number of debris robots may handle at a time.
* [ ] Only robots may handle debris in the play area. Teams may request a piece be moved after initial distribution in the play area.&#x20;
  * [ ] Moving debris is up to the Judge's discretion, but may be considered if the debris is damaged, stuck, stacked, on an obstacle, etc.&#x20;

## Playing Rubble Robots

#### Debris Randomization

Debris should be placed before a team is preparing to play. It's recommended to encourage students spectating to aid with placement so long as placement is fair (ex: debris not half outside the play area or stuck against an obstacle).&#x20;

#### Completing a Round

1. After debris has been distributed on the field, the team may begin their match time by notifying the judge. During their 5 minutes, teams may discuss and strategize or make small changes to their robot before beginning the 2 minute run period.&#x20;
   1. Only one robot and team should be allowed in the play area at a time.
2. Robots must be placed in the Robot Launch Zone before teams begin their run. The judge will give a brief countdown before the 2 minute run period begins.
3. Teams operate their robot to clean up the Construction Site. They may switch robot operators during their time frame.
4. The judge will record points and penalties during the run.
   1. Debris that enters a Collection Zone may be removed.
   2. Debris that exists the play area should be returned to a random location.&#x20;
5. When either the team has declared a run over, all debris has been cleared (correct or incorrectly), or time has expired, the judge will record the time and begin score calculations.
6. Teams should check in about scoring before leaving the field.

## Scoring

{% hint style="info" %}
This activity is intended to be for fun and skill building. Scoring is not intended to reflect that seen in competitions, but should be considered adjustable to suit the needs to participating students.
{% endhint %}

While a team is attempting the challenge a judge will record the following:

* Total number of debris collected in each of their correct Collection Zones
* Debris accidentally placed in the incorrect zone
* Final time for the run attempt
* Other penalties that occur

#### Score Breakdown

<details>

<summary>Debris Scoring</summary>

<table><thead><tr><th width="228.60003662109375">Debris</th><th>Collected (C)</th><th width="148.7999267578125">Point Value (PV)</th><th>Total Points = PV x C</th></tr></thead><tbody><tr><td>Trash Debris</td><td></td><td>5</td><td></td></tr><tr><td>Environmental Debris</td><td></td><td>5</td><td></td></tr><tr><td>Structural Debris</td><td></td><td>15</td><td></td></tr></tbody></table>

**Note:** Debris placed in the incorrect Collection Zone, including robots passing through the Zone with debris or temporary placements, should be removed and will no longer be eligible for scoring.&#x20;

**Total Debris Score** (Trash Debris + Environmental + Structural):  \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

<br>

</details>

<details>

<summary>Time Scoring</summary>

If the attempt ends before all debris is removed from the field: Final Time = 120 seconds

| Description                  | Recorded (R) | Time Points = 120 - R |
| ---------------------------- | ------------ | --------------------- |
| Final Time (Max 120 seconds) |              |                       |

**Time Score**: \_\_\_\_\_\_\_\_\_\_\_\_\_\_\_

</details>

<details>

<summary>Penalties</summary>

**Descriptions:** Violations to game rules. Light taps/brushes/interactions to an obstacle should not be considered a penalty. The penalty applies when there is noticeable or large movements, displacement from the original location, or damage.

<table><thead><tr><th width="289.4000244140625">Description</th><th>Recorded (R)</th><th>Penalty Points (P)</th><th>Total Points (= R x P)</th></tr></thead><tbody><tr><td>Debris placed in the incorrect Collection Zone</td><td></td><td>15 per debris piece</td><td></td></tr><tr><td>Robot left the play area</td><td></td><td>10 per leave</td><td></td></tr><tr><td>Robot was handled outside the Launch Zone</td><td></td><td>10 per handling</td><td></td></tr><tr><td>Robot entered, pushed, moved or otherwise displaced an obstacle</td><td></td><td>10 per incident</td><td></td></tr></tbody></table>

**Total Penalty Points:** \_\_\_\_\_\_\_\_\_\_\_\_\_

</details>

#### Final Point Calculation:

(Target Score + Time Score) - Penalty Points = \_\_\_\_\_\_\_\_\_\_\_\_\_

#### Printable Score Sheet

{% file src="/files/4JOgx6fPB3nfvyR8kmGk" %}

## Activity Expansion Ideas

#### Changing Obstacles&#x20;

Obstacles may be added, removed, or their locations may be randomized between attempts from teams to complete the challenge. Changing obstacles creates new opportunities for teams to strategize their approach or consider making changes to their robot!&#x20;

Similarly, debris may be added or changed to create additional challenges.&#x20;

#### Construction Robots

Consider adding an additional challenge for robots to place or move objects after the debris within the construction area is cleared. This may include placing something on top of an obstacle, placing a new obstacle, or rearranging the obstacles to appropriate locations.&#x20;

It's recommended to start simple with placing a single object in a randomized location as a sort of "end game" before expanding too much on this concept.&#x20;