ES.293 | Spring 2007 | Undergraduate
Lego Robotics

The Fire-Fighting Robot


Home FireGuard™ is a U.S.-based company specializing in the supply of fire detection and fire fighting systems to homeowners. They already sell common fire detection and prevention systems such as smoke detectors, sprinkler systems, and alarm systems that contact the fire department when a fire is detected. However, they are only one of thirty-three major suppliers of such systems, and competition is fierce. They hope to take a stride ahead of their competitors by introducing the fire-fighting robot. They hope the fire-fighting robot will fill the deficiencies of smoke detectors, sprinkler systems, and fire department notification systems. These are:

  • Smoke detectors only warn of a fire, and do nothing to put it out.
  • Sprinkler systems often cause severe damage to the contents of the rooms they activate in, and are especially dangerous in rooms containing expensive electronics, art, etc.
  • Fire department notification systems take a substantial amount of time to summon help to the scene.

Home FireGuard™ visualizes a robot that is activated by a fire detector similar to those used to notify fire departments. The robot then traverses the house until it finds the fire and extinguishes it. Home FireGuard™ already stores the floor plans of all houses that have service contracts with it on computer. Because of this, they believe they can transmit the floor plan of the current house to the robot so it knows the layout ahead of time.

They have contracted you, the designer, to design and build a robot that, knowing the floorplan of a house ahead of time, can navigate the house, locate the fire, and extinguish the fire. For your first presentation to them, they want to see a small robot that can do this in a model house, to demonstrate your ideas have merit. After you pass this review, you can go on to building the full-size robot that will navigate a full-size house.


Unfortunately, you haven’t really been hired by a company to build robots. You don’t own your own robotic design company yet. And we don’t have the supplies to build huge robots that explore five-story Boston brownstones. So we’re scaling the above project down into the LEGO® robotics world and the size of robots we’re used to working with. In addition, because it is more difficult to build a multi-story model house capable of supporting a robot’s weight, and because stairs pose a huge challenge, we will be restricting the house to one story.

House Details

The house will either be laid out in the biology lab or a similar place with a smooth, white floor, or the house will have a built-in smooth white floor. The walls will be made of wood or thick cardboard, as yet undetermined, and may be painted some color. The ceiling will be open to allow easy placement of the robot and to let us watch the robot in action.

For the purposes of your design, assume you are designing the robot to fight fires in one specific house. See figure 1 for the floorplan of this house, accurate to 0.5 inches.

Figure 1:


Fire Details

For general safety reasons, and because components are both expensive and damaged by fire, we will not be using a real fire. The fire will be represented by some bright light source, possibly a full-size light bulb in some sort of mounting. In addition, the floor and walls of the room containing the fire will be painted or taped black. This represents the smoke that is filling the room.

There are several ways of ’extinguishing’ the fire. Currently, the suggested methods are dumping foam pellets on the fire or throwing foam blocks at the fire. These represent smothering the fire with some chemical extinguisher. You are free to propose other analogs for the fire extinguishing process (firing a squirtgun, releasing air from a balloon, whatever you can think of). Whatever method of extinguishing the fire is chosen, if the extinguishing material (foam, water, air) comes into contact with the light bulb or its base, the fire is considered successfully extinguished.


This project is mainly a competition between you and the free time you have/want to spend working on it. The main purpose of the project is to build a robot that accomplishes at least partly the firefighting goals. There may be a competition for those who wish to enter to see whose robot can extinguish the fire most reliably and quickly. More details will be forthcoming.

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