This wearable LED heart simulator pendant was inspired by my work as a cardiovascular surgical nurse as well as my love of electronics. It simulates the electrical activity of 17 different rhythms and when paired with the heart backplane, it becomes an audio and pulse simulator as well.

It is not so much a kit as it is highly over-engineered LEDs, but I hope you enjoy them anyway! The program will be loaded onto the eeprom for you, but you are more than welcome to use a propplug, provided by Parallax, Inc., to reprogram the Propeller chip with whatever program you would like!



Who would want these?!

Nurses, doctors, any healthcare providers, or even folks who think the heart is a pretty cool organ!

What do I need to know to get this working?

Due to restrictions on shipping lithium batteries, the 2 CR2032 3v lithium batteries will not be provided (so you’ll need to get those yourself).

The program will be already programmed onto the EEPROM.

If I want to do something else with this board, what do I need to know?

The MCU on the board is a Parallax Propeller and the EEPROM is a 24LC512 from Microchip. It is programmable using a PropPlug (found at http://goo.gl/0TuPR)

Note that VSS (GND) is on the left. A header is provided should you choose to solder it in - but is unnecessary for programming, you can just stick the header in the propplug, temporarily place it in the header holes and program it that way.

The switch is on pin 5. SA Node is on pin 6. AV node is on pin 7. Left Bundle Branch is on pins 19-23. Right Bundle Branch is on pins 8-13.

Accessible pins are: 0-3, 7, 14-18, and 24-27.

There is also a hole on the top right of the board - that is not connected to any part of the circuit and is useful for putting any chain or pin through it for wearability!

Rhythms Simulated:

The SA, AV, and Bundle Branches are simulated in this wearable heart. The timing is accurate to the actual rhythms as well.

• Normal Sinus Rhythm
• Sinus Bradycardia
• Sinus Tachycardia
• Atrial Fibrillation
• Atrial Flutter
• Supraventricular Tachycardia
• Ventricular Fibrillation
• Ventricular Tachycardia
• Sinus Rhythm with a 1st degree atrioventricular block
• Sinus Rhythm with a 2nd degree atrioventricular block Type 1
• Sinus Rhythm with a 2nd degree atrioventricular block Type 2
• Third degree atrioventricular block
• Sinus Rhythm with a Bundle Branch Block
• Junctional Rhythm
• Idioventricular Rhythm
• Normal Sinus Rhythm with Pre Atrial Contractions
• Normal Sinus Rhythm with Pre Ventricular Contractions
• Off (Propeller still on)

Video showing it working:



Note that because we wanted to keep the video bright, the LEDs are slightly washed out in the video. When you’re looking at them normally, they’re really quite bright. Example:



Example of what’s been done with it: http://www.youtube.com/watch?v=pZOHqvAeGIo