Collaborating with the Atlanta Fire Department, researchers at Georgia Tech have developed a virtual-reality (VR) based fire command training simulator to better prepare fire officers to react in emergencies.
The software itself simulates the progress of a fire in a single-family home and responds to the orders made by a fire commander on the scene. The virtual environment allows the user to navigate around the fire scene and view a house on fire from any angle, to direct firefighters and watch them execute commands. It also lets them see how fire and smoke reacts to changes in the environment, such as the opening of windows.
Dr. Chris Shaw, a senior research scientist in Georgia Tech’s College of Computing Shaw and his team of students, created the virtual environment with a furnished one-story house with a garage, a fire truck, firefighters, tools, and fire hydrant. The user, the fire company officer, sees the house on fire on a computer screen or a head-mounted display and gives verbal commands as he would in a real fire.
The system operator types the officer’s commands into the computer system via code. The project team decided to handle the command input in this fashion rather than incorporating a voice recognition system to translate the voice commands due to their unreliability for multiple users. Also, having an operator input the commands, rather than the user, allows the user to concentrate on evaluating the situation and making decisions. This arrangement also allows the operator to set up mistakes or traps for the user, again creating a more realistic experience.
The officer then sees animated firefighters reacting to his commands – such as laying hoses or climbing onto the roof to cut a hole over the fire. Also, every 15 seconds, the visuals of the smoke and fire change in reaction to the officer’s commands.
Due to the complexity of calculating the amount of smoke and fire produced, the team used the National Institute for Standards and Technology (NIST)’s Fire Dynamic Simulator to compute realistic physical fire and smoke behaviour.
Due to the length of time it takes to accurately compute the volume of fire and smoke, the team pre-computed the data for the entire house at one-second increments, and the system used the pre-computed data to visualise and animate the fire and smoke in the virtual environment. On a current PC, the Fire Dynamic Simulator would take about eight hours to compute one minute of data, making it impossible to calculate the smoke and fire in real time.
Other challenges the team faced in the development of the software included the need to develop compression techniques to make the huge data files manageable. The growth of choices and conditions – such as opening doors, spraying water – result in an exponential increase in data.
Also, the team had to create realistic-looking 3-D visuals of fire and smoke to accurately indicate to the officer the amount of soot, heat and smoke. At the scene of a real fire, officers look for these factors to determine the cause and type of fire to guide their decisions.