RoboCupJunior Rescue Maze — Exploration, Mapping and Victim Rescue

Where Rescue Line asks for a robot that follows a known route well, Rescue Maze asks for a robot that does not know where it is. The arena is an unknown maze the robot must explore on its own, find victims in, and finally navigate back out of.

Technically it sits a step above Rescue Line, and it is usually the next league for students who have cleared that stage.

Field structure

A tile grid whose wall layout is unknown in advance.
Ramps or multiple levels — the maze can change height.
Black tiles — forbidden zones; entering costs points and the robot must back out.
Difficult surfaces such as raised or slippery areas that disrupt motion.
Checkpoints the robot restarts from after a failure.
Victims mounted on the walls.

How victims are identified

Visual victims — a marker or letter on the wall, detected with a camera and image processing. Each marker means something different and calls for a different rescue kit.
Thermal victims — a heated spot detectable only with an infrared/thermal sensor.

On detection the robot must stop on that tile, signal, and deploy rescue kits — the number depending on victim type. Misclassifying a victim wastes both kits and points.

The hidden points: getting home. A substantial bonus goes to robots that return to the start tile after exploring. That means the robot must have remembered where it went — which turns Rescue Maze from a driving exercise into a genuine algorithmic problem.

Algorithms are the heart of this league

Exploration

The simplest approach is right-hand-on-wall. It works, but it is not optimal and on some layouts it never sees part of the maze. Serious teams switch to graph-based exploration: each tile a node, each opening an edge, explored with DFS or BFS.

Mapping and localisation

The robot must build an internal map and know its place in it. Encoder drift and wheel slip become the main enemy; without constant correction from distance sensors, the map is worthless after a few tiles.

Path planning for the return

Getting home runs a shortest-path algorithm such as flood fill over the built map — the same technique used in Micromouse.

Suggested hardware

Distance sensors on four sides for wall detection
A gyroscope or IMU for accurate 90-degree turns
A camera for visual victims and a thermal sensor for heated ones
A kit-dropping mechanism
A processor beyond a simple microcontroller, because of the vision work

How long does it really take?

For a team with Rescue Line experience, roughly 6–9 months to competitive readiness. A brand-new team should spend a season on Rescue Line first. Novin Zehn maze teams follow exactly that stepped path.

Frequently asked questions

Is Maze harder than Rescue Line?

Noticeably, yes. Rescue Line is mostly motion control; Maze adds vision, thermal sensing, mapping and path planning.

Is a camera mandatory?

For visual victims, yes. Some teams start by targeting only thermal victims, but they give up part of the score.

What are the prerequisites?

Solid motor control, distance-sensor work and structured programming. Familiarity with Python or C++ helps a great deal for the mapping side.

Want to compete in Rescue Maze?

Novin Zehn competition teams train from zero to the world stage — in Tehran and live online.