2 independent portable electronic devices that detects when they are separated.

I am looking for the design and implementation of technology to create 2 electronic devices. A master (primary) device that beeps/vibrates when the slave (secondary) device moves more than a few meters away from it.

## Deliverables

Requirements:

**Master device** to be battery powered with long life, as small and light as possible. Must have an alert mechanism like beeping and vibrating to alert a person with the master device when the slave device has moved away from it by more than a few meters.

**Slave device** is to be very small and very light and very cheap to make. (Slave devices may be disposable items). It must be able to be registered/detected by the master device without physical connection.

Considerations:

**1.** One master device needs to be able to have many slave devices connected to it.

**2.** One unit of master+slaves should not interfere with another unit of master+slaves. That is two master devices should not interfere with each other or the slave devices that belong to the other master device.

**3.** Need to mass produce these, so cost to manufacture must be cheap.

**4.** Devices must have a lifespan of at least a few years.

**5.** More important that the slave devices are cheaper and smaller and lighter than the master device. But master device still has to be small and light.

**6.** Need a way to register new slave devices (and remove old ones) to the master device at any stage.

**7.** the master device must react whenever a slave device moves out of its range of a few meters by beeping/vibrating. The user must then be able to switch this off.

**8.** when a slave device that is far away comes into range of the master device, it also needs to beep/vibrate.

Results

**1.** Need the electronic design of these devices.

**2.** I need to know the most economical way of doing this while keeping the devices as small as possible.

**3**. How much would it cost to mass manufacture these devices.

**4.** Where could I get these devices manufactured.

Maybe an implementation of RFID technology?

Elektronik

Projekt ID: #3500855

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