Search and Rescue Unit Design Team


Team Members: (from left) Todd Taylor, Jen Bogard, John Chai, Aaron Richer, Daniel Grant


Sponsor: PSU Applied Research Laboratory - Thomas Gabrielson


Advisor: Tim Wheeler


Introduction

Rescue personnel have long had trouble finding survivors in collapsed or fire-damaged buildings. These situations are dangerous not only to those trapped, but also to the rescuers who must explore wreckage to find them. Rescuers have also reported difficulty in hearing survivors who are buried under rubble. The search and rescue detection module designed by Thomas Gabrielson attempted to solve these problems. Rescuers can toss Gabrielson's ball into rubble and find out if any movement or sound is present.

The module Gabrielson designed had three infrared sensors to detect motion and a microphone to pick up sound. If motion was detected, a signal was sent in Morse code to a handheld radio. Then a button on a handheld device was pressed to select "listen mode" on the ball. In "listen mode", the microphone's signal was sent to the handheld radio, so one could listen for signs of life where motion was detected. If the button on the handheld device was pressed again, the ball went back into motion detection mode.

Objectives

The Search and Rescue Unit Group has been assigned five basic tasks to improve the design of Gabrielson's module:

  1. Replace the current single-channel 433.9 MHz transmitter in the ball module with an 8-channel 900 MHz transmitter. The transmitter frequency should be switchable with a BCD switch. This way, 8 balls can be in the field at once without interfering with each other.
  2. Change the code transmitted by the ball from Morse Code to a digital ID. This digital ID will also be used to identify which ball is sending a signal.
  3. Design and build a 900 MHz receiver/decoder to receive this digital ID and display which ball is detecting motion using LEDs.
  4. Add a BCD switch to the command transmitter, so one command transmitter can control up to 8 balls separately.
  5. Improve the command string being sent from the command transmitter, using error checking.

Figure 1: Finished board to be included in ball module