WO2019222785A1

WO2019222785A1 - Sleep safe alarm device

Info

Publication number: WO2019222785A1
Application number: PCT/AU2018/000077
Authority: WO
Inventors: Sash RISTOVSKI; Angela RISTOVSKI; Goce RISTOVSKI
Original assignee: Ristovski Sash; Ristovski Angela; Ristovski Goce
Priority date: 2018-05-21
Filing date: 2018-05-21
Publication date: 2019-11-28

Abstract

The technical development of the Sleep Safe product is intended to assist the hearing impaired to become aware of a smoke detector becoming active in their home. It will allow the person to wake safely and evacuate. It does this by detecting the smoke detector alert then providing auditory, visual and vibration alerts to wake the sleeping person. The Sleep Safe alarm system will be able to sense the house smoke detector siren wirelessly. The alarm detector listens to the smoke detector and communicates with the Base Unit. Once the smoke detector siren is sensed by the Sleep Safe unit, it will then switch on immediately and warn the sleeping person with a bright light, audible voice alarm announcing WARNING, FIRE, WAKE UP and also a vibrating pad directly wired from the Sleep Safe unit to the pillow or mattress pads. The Sleep Safe alarm system comprises of an Alarm Detector to this frequency band and has the advantage with longer wave-length and better wall penetration. The Alarm Detector includes an external microphone so that it can only detect the smoke alarm siren.

Description

Background Description

The technical development of the Sleep Safe product is intended to assist the hearing impaired (either severe or profound) to become aware of a smoke detector becoming active in their home. It will allow the person to wake safely and evacuate. It does this by detecting the smoke detector alert then providing auditory, visual and vibration alerts to wake the sleeping person.

The Sleep Safe alarm system, will be able to sense the house smoke detector siren wirelessly. The alarm detector listens to the smoke detector and communicates with the Base Unit using the radio frequencies 915MHz, 900MHz or 868Mhz band. Once the smoke detector siren is sensed by the Sleep Safe unit, it will then switch on immediately and warn the sleeping person with a bright light, audible voice alarm announcing WARNING, FIRE, WAKE UP and also a vibrating pad directly wired from the Sleep Safe unit to the pillow or mattress pads.

The Sleep Safe alarm system comprises of an Alarm Detector to this frequency band and has the advantage with longer wave-length and better wall penetration. The Alarm Detector includes an external microphone so that it can only detect the smoke alarm siren.

The Sleep Safe unit can also be classified as a primary safety unit as well as an assisting product for a smoke detector for the hearing impaired.

Claims

Claims - Deliverables

The available technologies suited to be implemented as a product are outlined and short listed for consideration. The primary deliverables are:

• Basic technical analysis of requirements

• List of considered implantation technologies

Technical Analysis of Requirements

This section will discuss the technology options and implications for each of these. It will also identify the requirements that are suggested as a project option.

^■ Radio Communications

Both radio technologies of WiFi and Bluetooth are not suitable for the primary communications between the smoke alarm detector and the unit that provides the visual, audible and vibration alerts. The reasons for this are outlined below; following this, some suitable options and the reasons for their consideration are outlined.

^■ Wifi

Wifi is both hungry and also difficult to set up. Many household appliances that use Wifi require a level of technical ability that is beyond many consumers. It is also one of the more expensive options. So it is not recommended for all 3 of these reasons:

• Power requirement

• Difficulty to configure

• Highest unit cost

^■ Bluetooth

Bluetooth was originally designed a short range wire replacement technology to allow things like wireless headsets for listening to music and hands free units for answering phone calls without having to touch the phone. In this application they work well.

This is the best option for connecting to a modern mobile phone (smart phone) and therefore, should be considered for that interface.

Bluetooth is low power and relatively inexpensive. The range is 50m maximum in ideal circumstances and is as little as 5m less in ideal circumstances. It can't be relied upon for communications beyond 10m and isn't suitable for penetrating walls and dense materials. As an example, in a radio communications environment, internal brick walls of a book case would be considered a dense material.

^■ Other 2.4GHz options

A wide range of other 2.4GHz options exists and has the advantage of a world standard. It can be shipped out anywhere in the world. The drawbacks are; they are expensive (such as Wifi) or have poor range (such as Bluetooth). There is also a band where congestion can be high and it's expected to get worse as more video streaming over Wifi and the like are used.

Low data rate industrial standards such as 802.15.4 and ZigBee are designed to give way to Wifi and other high bandwidth services. They can reach the point where they do not work at all in high congestion. This is unacceptable for a product that is augmenting a safety system like a smoke alarm.

Therefore, we are ruling out all the 2.4GHz option on the basis of cost, range and the possibility they do not work in critical circumstances.

^■ 433MHz

Australia allows for radio communications in the 433MHz band. This has the advantage of longer range because the power levels allowed on the radio communications are much higher and, the longer wavelength makes wall penetration better.

The drawbacks are that every remote control car and garage door opener is using this frequency and the antennas need to be longer meaning, the unit that detects the alarm has to be physically larger.

This frequency band is not available everywhere so this would be considered for an Australian only version of this product.

^■ 915MHz

This frequency band has the advantage of 433MHz with the longer wavelength and better wall penetration however, the power levels must be lower. It has a big advantage in that, it is for Industrial, Scientific, Medical and short range communication devices hence, they do not have the interface from remote controls and the like.

Internationally, either 915Mhz, 900MHz or 868MHz bands are used and so, a simple variant on the primary product would be able to be sold anywhere in the world.

These are cost effective chipsets that are available from Atmel, Texas Instruments and Nordic Semiconductor that can be used to implement communications in this band.

For example; the antenna sizing suits a compact product. Radio Communications Recommendation

On the bases of range, cost, size and the power consumption the best option is radio communication in the 915MHz band.

In general terms, the development expenses associated with each of the radio types are similar and are not distinguishing elements.

Most radio communications systems can be developed so that multiple alarm detectors would be able to communicate with a single base unit. This would be desirable as most homes have multiple smoke detectors.

^■ Smart Phone Features

A number of smart phone features are proposed. These include;

• Setting alarms for vibration only

• Sending alerts for the fire brigade and to other family members

The best method for communicating between the smart phone and the Sleep Safe base unit (bedside) is Bluetooth. The primary challenge is to pair the devices to the smart phone so that only the owner of the Sleep Safe device can make adjustments and not anyone visiting the house that has the same smart phone. This is best handled by using a pin code for the Sleep Safe device.

Adding Bluetooth will add to the unit cost. Typically you can expect this to cost $6 per unit in the modest quantities of 1000 units manufactured.

The extra development cost for the base unit and smart phone app will lead to enough extra unit sales. This is a commercial rather technical consideration. Technically it is achievable.

Each pillow vibration unit will need to be driven separately for an extra pillow unit driver.

The App will require the largest development budget for this feature to cover for both iPhone and Android smart phones.

The MBF or CFA already provide TTY interfaces on fire alerts for the hearing impaired.

SMS alerts to other family members is definitely possible as is an alert message that triggers the phone to do more than just acknowledge the SMS. This would most likely be an extension of the App Development.

^■ Standards Compliance

The Sleep Safe is compliance with AS3786 and AS1603.17. The mandatory standards for EMC compliance and safety still apply. Vibration Alerts

Wired vibration units for use under pillows is a standard technology and available off the shelf from the number of vendors. No specific technical risks exist with this technology.

Wireless vibration alert units also exist. They are more expensive and they also introduce extra issues such as battery management, RF present close to the head can have some health concerns.

Overall, cost and risk are lower with wired units.

^■ Battery Back Up

Given the recent changes in legislation for Lithium Polymer batteries and long life expected of a unit like this, we recommend NiMH batteries for battery backup of both the smoke alarm detection device and he base unit.

In general, devices like this have a 10 hour battery backup period however extending this to 24 hours of operation without mains present is readily achievable. The actual operating time during a fire is quite short and should not require more than 5 minutes of vibration.

^■ Smoke Alarm Detection

This is best done in the audible domain however, there are no guarantees the smoke detector will have an externally accessible trigger point available for when it is in alert. These are not mandatory for the household smoke detectors and not intended for remote alarm activation.

The smoke detector output has a distinctive pulse as well as a narrow frequency pitch. In order to keep power consumption low in the detecting device (so it does not require huge standby battery) it is best done in an analogue circuitry.

After reviewing the options the following scheme is recommended:

• A sensitivity adjustment might be required. This can be explored in the prototype phase.

• A narrow band filter for looking at just the frequency range used by smoke detectors. This includes the lower frequency allowed for in the hearing impaired smoke detectors.

• To add a pulse discriminator to determine if the sound is being heard or, not being heard at the right rate to be an adequate smoke detector

• Allow for a minimum number of activations before sending the alert. This is at least 2 but could be as much as 5. The reason for the minimum number of activations is that many sounds can approximate a smoke detector briefly. This includes young children squealing and certain types of toys. The likelihood of this is that they can consistently meet the sound level, frequency and the pulse repetition rate of the smoke detector. A short time reduces certainty, a long time increases it. And of course, too long a time leads to reduces safety in the event of a real alert situation. The best case scenario would be a minimum of 5 pulses would mean around 5 seconds of confirmation before the alert was passed on.