Emergency Child Guidance System

Emergency Child Guidance System

Final Report

Team: May 01-03

Team Members:

Abbey Arends

Chris Bloomquist

Lisa DeLashmutt

Karen James

Angela Nystrom

Client Names: Patterson & Lamont

Faculty Advisors: Patterson & Lamont

Date Submitted: April 16, 2001

TABLE OF CONTENTS

LIST OF FIGURES

LIST OF TABLES

Introductory Materials

Executive Summary

Acknowledgements

Definition of Terms

Introduction

General Background

Technical Problem

Operating Environment

Intended Users and Uses

Assumptions and Limitations

Design Requirements

Design Objectives

Functional Requirements

Design Constraints

Measurable Milestones

End Product Description

Approach and Design

Technical Approach

Technical Design

Testing Description

Risks and Risk Management

Recommendation for Follow-on Work

Financial Budget

Personnel Effort Budget

Project Schedule

Closure Material

Evaluation of Project Success

Commercialization

Recommendation for Additional Work

Lessons Learned

Project Team Information

Summary

References

Appendix A – User’s Manual...... A-

Appendix B – TRF4900...... B-

Appendix C – TRF6900...... C-

Appendix D - Microphone-to-Transmitter Schematic………………………………….D-1

LIST OF FIGURES

Figure 1 – ECGS Design...... 4

Figure 2 – Alarm sensor………………………………………………….………………12

Figure 3 – Central transmitter……………………………………………………………13

Figure 4 – Battery-powered light………………………………………………………...14

Figure 5 – Rechargeable light……………………………………………………………14

Figure 6 – Project schedule...... 18

LIST OF TABLES

Table 1 – Financial Budget...... 16

Table 2 – Personnel Effort Budget...... 17

Introductory Materials

Executive Summary

The goal of this project is to design, build, document, and test an emergency child guidance system (ECGS). The system triggers from the sound of a common smoke alarm and will guide children to safety during a household fire. The ECGS targets children between the ages of two and eight years. This system will help reduce the number of deaths during household fires.

There are many deaths every year because of household fires. The majority of casualties in fire-related deaths are children. One of the reasons for this is because children panic in emergency situations. For example, when a smoke alarm triggers, it produces a very loud sound, which often terrifies young children. Terrified children all react differently. Some simply pretend that the fire is not happening. Others hide in their closet to escape. The goal of the ECGS is to provide a consistent and safe route of exit for the child during the fire.

The ECGS was implemented using a smoke alarm, alarm sensor, central transmitter, voice recording, and a set of lights along an escape route. One of the smoke alarms detects the fire and emits the high-pitched sound. One or more of the alarm sensors pick up the sound and send a signal using the some frequency to the central transmitter. The central transmitter’s logic determines where the fire was sensed and outputs the signal to light up the correct set of lights. The lights receive the signal from the central transmitter and light up the route leading to the safest exit. As the child passes each light and presses it, a pre-recorded message to aide in the exit will be played. Refer to Figure 1 for a diagram.

The entire ECGS was not fully implemented, but an operating prototype was implemented. The ECGS prototype includes a microphone-to-transmitter combination. An amplifier was used to increase the frequency of the sound of the smoke detector. Then a diode and an integrator were added to make the signal produced stay large over an extended period of time. The reason for this is to differentiate the noise of the detector from other loud noises such as a screaming child or loud music. Lastly, the non-inverting comparator was added to make the on/off switching more assured. For the receiver-to-light combination, a simple relay was used to switch the lights. As a result of the prototype, a demonstration will be given to the industrial review panel.

Acknowledgements

The May 01-03 group would like to acknowledge Dr. Lamont and Dr. Patterson for the extensive amount of advice, research, and technical support provided throughout the ECGS project.

Definition of Terms

ECGS – Emergency Child Guidance System

Smoke alarm – The common, everyday smoke alarm in households.

Alarm sensor – It is activated by the sound of the smoke alarm and sends an analog signal to the central transmitter.

Central transmitter – Contains the logic, transmitter for lights, radio transmitter, recording device, and voice recording equipment.

Voice recording – The personalized message from the central transmitter.

System – The entire ECGS.

Devices – Refers to one of the following: alarm sensor, central transmitter, and lights.

Introduction

General Background

Many children die during household fires because of the lack of guidance during an emergency situation. This system, which triggers off of the sound emitted from a smoke alarm, will use a pre-recorded voice and a path of lights to direct the child to safety. The devices included in the system are alarm sensors, a central transmitter, battery powered lights, and rechargeable lights. The alarm sensors will be mounted near the smoke alarms already in the household. The central transmitter will be placed away from the smoke alarms, and the lights will be strategically placed in a path routing a safe exit. The system is outlined in the Figure 1 and described thoroughly in the technical design.

R Route

Figure 1 – ECGS Design

Technical Problem

As seen in Figure 1, one of the smoke alarms detects the fire and emits the high-pitched sound. One or more of the alarm sensors pick up the sound and send a signal using a particular frequency to the central transmitter. The central transmitter’s logic determines where using the frequency of the signal received from the alarm sensor sensed the fire. It then outputs the correct of lights to turn on using the appropriate frequency. The route of lights receive the signal from the central transmitter and light up accordingly. If pressed, each light plays a pre-recorded message explaining how to exit the house safely.

Operating Environment

The central transmitter will be located where fires are less likely to reach and will be in a fire-retardant case. The casing for all of the devices will be waterproof for customers owning a fire-activated sprinkler system. Also, the casing must be somewhat durable in the event of explosion or destructive conditions. During the loss of power, the system will continue normal operation.

Intended Users and Uses

USERS - The product targets the general public with 2-8 year old children living in the home. The ECGS may also be modified for use in daycares, nursing homes, etc.

USES - The system will calmly communicate with the child during a household fire, directing the child to safety.

The ECGS should not be used as a replacement for other fire-safety measures, and the system must be rehearsed with the intended user.

Assumptions and Limitations

Assumptions:

The customer will need to have at least one smoke alarm installed

When children are not under adult supervision, they are assumed to be located in their bedroom or playroom. This must be assumed to ensure that the path of lights will lead them from this room to a safe exit.

Limitations:

The success of the system depends on the reliability of the smoke alarm.

The smoke alarm and the system components must all be checked regularly to see if the batteries are charged, and they must be checked regularly for the low-battery light.

The customer must understand that at some point during the fire, it will be impossible to prevent the system from succumbing to the fire.

The child may not respond to the voice or light guidance.

The system does not guarantee to save the child’s life.

The lights must be visible in the smoke.

There might not always be a safe route.

If there is a false alarm, the ECGS will react as though there were a real fire. This will provide the children a chance to practice exiting safely.

Design Requirements

Design Objectives

(Please refer to the figures in the technical design.)

Functional Requirements

Smoke alarm

Batteries: It is assumed that most smoke alarms require batteries for adequate power.

Alarm sensor

Batteries: It is assumed that the alarm sensor will require batteries for adequate power.

Sound receiver (microphone): The alarm sensor’s receiver picks up any audible sound within range.

Transmitter: A transmitter will send an analog signal to the central transmitter to activate the rest of the system.

Central transmitter

Batteries: It is assumed that the central transmitter will require batteries for adequate power or an AC power supply with a battery back-up.

Signal receiver: The central transmitter’s receiver will pick up the analog signal sent by an alarm sensor.

Signal transmitter: The central transmitter will transmit an analog signal to the touch lights, turning on the appropriate path.

Logic: The logic will control the internal logic for selecting the correct route of exit.

Touch lights

Batteries: Batteries are needed to power each light.

Signal receiver: A signal receiver will be needed in every light to pick up the signal generated by the central transmitter.

Recording device: Each light will have a recording device. This device will encompass the functions of a common recorder such as play, record, and stop. Users will be able to customize their own message in order to fit their needs.

Light bulb: A small but bright bulb will light the casing of each touch light.

Logic: Simple logic will control the recording device, light bulbs, and receivers.

Design Constraints

Temperature: The ECGS must operate during a fire.

Water: The system must be waterproof.

Lightweight: The system must be able to stay mounted on the ceiling or wall.

Durability: To withstand volatile fire conditions, the system must be durable.

Power Loss: The system must be battery powered so that it will still operate under power outages.

Location: The alarm sensor will need to be within a few inches of the smoke alarm. The touch lights should be mounted as close to the floor as possible, and less than ten feet apart from each other. They are placed near the floor to keep the child low to avoid smoke inhalation.

** IT IS ASSUMED THAT UNDER EXTREME FIRE CONDITIONS, ALL OF THE DEVICES WILL EVENTUALLY FAIL.

Measurable Milestones

(GREATLY EXCEEDED, EXCEEDED, MET, ALMOST MET, TO BE MET, FAILED TO MEET)

Learn the functions, operations, and features of the household smoke detector. EXCEEDED

Research fire departments, smoke detector companies, child psychologists, and other knowledgeable sources.

GREATLY EXCEEDED

Finalize the design specifications.

MET

Explore all microcontroller options to select the most suitable for the system.

MET

Choose the most accommodating power source.

MET

Assure compatibility of the interface of the microcontroller with the smoke detector.

MET

Complete the design of the speakers and recordable device.

MET

Implement system components.

MET

Integrate system

MET

Test and re-evaluate the system.

MET

Debug and finalize the operation of the product.

ALMOST MET

Document.

ALMOST MET

End Product Description

The end product for this project contains a system designed to guide 2-8 year old children to safety during a household fire. The alarm sensor will be activated by the sound of the smoke alarm, and send a signal to the central transmitter. The central transmitter will send out signals to the appropriate lights. The lights, along with the recorded message, will then guide the children to safety. The standard package is designed for one route and one smoke alarm. It includes one alarm sensor, one central transmitter, and eight lights. Additional components will be available to modify the system for more escape routes and smoke alarms.

Approach and Design

Technical Approach

Before implementation, substantial information was gathered from professional sources such as Mr. Fred Malven, Nevada’s Fire Chief; Mr. George Oster, Ames fire-training center; a child psychologist; detector/alarm companies; and a potential customer to aid in the development. These sources provided input on the location, sound, and installation of the device. The questions asked and most common answers are as follows:

1. What color should the lights be?

Bright and easy to see in smoke – (white)

2. How far apart from each other should the light be?

About 5 feet

3. What distance can each device be from the smoke alarm?

Alarm sensors about 6 inches

4. Should the alarm sensors detect a signal or the sound from the smoke alarm?

Detect the sound b/c of liability issues

5. How much heat can the devices take before they fail?

Won’t really matter since at that point of operation, the child will not take that path anyway.

6. How much time for escape is there in a fire?

Depends on the smoke and carbon monoxide

7. What should be said in the message and how loudly should it be played?

Soothing message to ease the child out of the house

8. What age children should this target?

2-8 years old

9. Is the overall concept a good one?

Wonderful!!

10. Improvements?

Maybe some add-ons: a smart system, ropes or ladders, etc.

The information gathered from these sources was applied to the design and implementation of the child guidance system. Ideally, multiple smoke alarms and sensors can be implemented to choose the safe exit of a child. This involves the sensors triggering the central transmitter to activate different routes and voice recordings for the appropriate situation.

Before deciding which components to use on the prototype for the ECGS, car transmitters/receivers were researched, as well as many other commercial parts. In the end, remote control car transmitters/receivers were used in the implementation of the prototype. The schematic started with a microphone-to-transmitter combination. An amplifier was used to increase the frequency of the sound of the smoke detector. Then a diode and an integrator were added to make the signal large over an extended period of time. The reason for this is to differentiate the noise of the detector from other loud noises such as a screaming child or loud music. Lastly, the non-inverting comparator was added to make the on/off switching cleaner. For the receiver-to-light combination, a simple relay was used to get to the light. Refer to Appendix D for the schematic design.

Technical Design

(Please refer to Figure 1 for a picture of the technical design of the ECGS.)

Smoke alarms – The system would consist of the generic smoke alarms that most people have in their houses and apartments. The smoke alarms would be used in order to activate the ECGS. The alarm sensors would pick up the sounds from the smoke alarms and activate the system.

Alarm sensors – For every smoke alarm, there would be an alarm sensor. The purpose of the alarm sensor is to detect the noise from the smoke alarm. Then, the alarm sensor would send a signal to the central transmitter. If more than one smoke alarm is sounding, then all alarm sensors detecting smoke alarm sound would send signals to the central transmitter. The signals sent by each alarm sensor would all be of the different frequencies so that the central transmitter could interpret the location of the fire. The alarm sensors are further explained in Figure 2 below.

Figure 2 – Alarm sensor

Central transmitter –The central transmitter would receive the signals from the alarm sensors. Through the logic programmed in C, the central transmitter would be able to detect which smoke alarm was activated. Thus, it would be able to determine whether the child should follow the route that leads to the front door, the back door, or the window of the child’s bedroom. Also, the central transmitter would send the proper signals to activate the lights and the personalized voice recordings. Each light would have a receiver located within. The signal sent out by the central transmitter would have a different frequency for each light route. Thus, the correct route of lights would light up. Figure 3 below outlines the central transmitter.