VibeAware

About

We have created a wearable vibrating device with a corresponding remote. The device vibrates when the remote is toggled. The device can be placed inside the pocket or worn around the neck. The device was developed for a person who is deaf and has low vision.

Our product name is vibeAware, which is pronounced “Vibe - Aware”. It is a trifecta word pun: Our device allows its user to be aware when someone wants to notify her. It notifies the user with vibrations. The user can wear the device.

Vibration

We used a small vibration motor from Sparkfun.

Wireless Signal

To send a wireless signal, we used the Adafruit Single Button RF Remote Control - 315 Mhz

To receive the wireless signal we used Adafruit Simple RF L4 Reciever-315 MhZ Latching Selector Type

The video shows how simple it is to send and receive wireless signals using the Adafruit reciever and corresponding keyfob.

All photos are from sparkfun.com

The following are common circuit materials you should be able to find at a small electronics store.

• 100 ohm resistor
• 1k ohm resistor
• 2LN3904 BJT NPN Transistor
• Always connected toggle switch
• Always connected push button

• LM 7805 linear 5V voltage regulator*
• .1 muF capacitor*
• 33 muF capacitor*

• 9 V battery*

* The last four items were used to create a power supply with 5V and 1A current. You can use any method for creating this. We chose a 9 volt battery with a 7805 voltage regulator since they are both common, cheap, and easy to use.

Given a 5V 1A power source it's really easy to make on/off and reset switches. The schematic shows how we connected the push button, toggle switch, and LED to make an indicator light for when the circuit was on or off.

This schematic shows how we hooked up the motor. To get enough current to drive the motor we used a BJT NPN Transistor 2N3904. You can find its datasheet here.

We tested different resistor values for the resistor in series with the motor. We found 100 ohm had the best vibration, however I recommend testing out different values to get the best "buzz" out of your motor.

The resistor coming from "D2 Signal" is not required in our design. However, if you wish to use this in a different device you might need to drop down the signal to the Transistor.

We needed a 5V 1A power supply. To do this we used a 9V battery with the trusty LM7805. We hooked it up as specified in the data sheet for a Fixed-Output regulator. The image shown is directly from the LM7805 data sheet.

We first tested our design using a breadboard. The photo shows a clearer picture of the breadboard and the video shows the assembled device in action.

Schematic developed using SchemeIt from digikey.

Figure Name and Part Description

• Power source
  • 9 V battery
• C1
  • .1 muF capacitor
• C2
  • 33 /muF capacitor
• D1
  • LED
• M1
  • small cell phone pager motor
• Q1
  • 2LN3904 BJT NPN Transistor
• R1
  • 1K ohms
• R2
  • 100 ohms
• S1
  • Always connected toggle switch
• S2
  • Always connected push button
• U1
  • LM 7805 linear 5V voltage regulator
• U2
  • ADA Fruit Latch receiver

Once we had the circuit created, we wanted to enclose it. In designing the enclosure, we kept a few details in mind:

• Keep the motor to be close to the skin
• Put switches on the right side since client is right-handed
• Keep attena visible for maximum distance with solution
• Try to keep the size as small as possible

Here are the steps we took for creating the enclosure:

1. We started with box maker to create a box.
2. We imported the design into corel draw. Then we removed the parts of the box we didn't need.
3. We cut our design on cardboard to test it out first. Once we verified the dimensions, we cut the device out of acryllic. The files vibeaware.pdf and vibeaware.cdr show final design for the laser cutter.
4. The last step was enclosing the box using some hot glue. The wiring of the circuit was slightly messy, so we ended up having to use tape.

In our design, there are two switches on the right side of the device. The toggle switch is used to turn the device on and off. The pushbutton is used to reset the device. Since we are using a latching receiver, once the button is pressed and the signal is received the device will continue notifying the user until is is turned off or reset.

The video shows an example of using the assembled vibeAware.