Fire Fighting Robotic System Design
Noam Hileli & Daniel Shotts.
The system design:
The project objective, as part of the development of the robot by "Roboteam" company, which includes control system and mobility system, we will focus on designing and planning of the firefighting unit parts and installation on the robots platform. The project offers an ideal technological solution for effective and fast extinguishment, while avoiding life risking situations for man by a robot, which is remote controlled or autonomic with high capabilities of detecting and identifying fires and carrying a sufficient amount of firefighting agent more than a single fireman can carry.
Figure 1: Firefighting robot without the isolated cover
The main designs problems which we will address are: choosing the suitable equipment, fitting and installation on the robots platform, protecting the robot from heat and fire.
For the firefighting agent/equipment we decided to use is a fire extinguisher type LWC-50, foam fire extinguisher which is suitable for extinguishing solids and fluids. It is a standard product produced and manufactured by "LVT". The reason for this choice is taking advantage of a product which is already in use and its extinguishing capabilities are known and gives a good base for the reliability of the system.
The compatibility of the system - The design is kept simple and strong based on the existing robot platform. As so we decided that the direction were the fire extinguishing agent will be discharged will be based on the robots movement, in order to keep it simple and power saving. That's why the tap and nozzle are permanently fixed to the chassis foundation.
Figure 2: Design of the chassis
In appendix A you can find more detailed technical drawings of the mechanical design. We decided to harness the extinguisher at an angle of 40° degrees in order to enable efficient discharge of the firefighting agent even while the whole platform is at an angle as explained in Section 6.1. We calculated the center of mass location and found that the robot can operate without rolling at an angle up to 37° degrees on the sides and up to 50° degrees on the front and back.
Protection of the system - We were required to find the insulation material which will be used for the outer shield. We found a ceramic blanket manufactured by IV&R (appendix C) with the suitable properties for our demands. A shield from this material provides the system sufficient time in a fire environment, so the temperature inside will not exceed 60°C which could damage the electronic system equipment who are the most sensitive to heat. In Section 6.3 we have shown a calculation of the heat transfer which demonstrates the insulation capabilities, and you can see a heat transfer analysis done on COMSOL program which confirms the calculations. We found that in the temperature of 500°C (the temperature felt 4-5 meters away from a fire) it will take more than 3 minutes to exceed 60°C at the inner surface of the cover.