Hi, this is Wayne again with a topic “Sylvia’s Super Awesome Mini Maker Show: Make a Heartbeat Pendant”.
Welcome to sylvia super awesome, mini maker show season three episode, one on this episode: we’re gon na look deep, deep into your body to find out what makes you tick it’s your heart, but we don’t need to cut you open to learn more about it all. We need is a little green light today, we’ll be making an arduino based pendant that flashes to your heartbeat with a super awesome, open source pull sensor. Let’S go for this bloodtastic build. We will need an arduino i’ll be using the protosnap lilypad development board available from the maker shed, but any kind will do 3 or 5 volt. The pull sensor kit, also from the maker shed small gauge wire, soldering iron solder and a hot glue gun, an old silver chain or cord necklace, some small, assorted, leds and finally, a makeshift pendant. It could be paper, leather or an old pendant. You want to upgrade.
I’M going to use this cool example pcb i got from seed studio first, let’s prep our pendant plan out what leds you want on it and how you’re going to wire them we’ll be tying into pin 11 and ground so in one led lights, they’ll all light Straight from the logic voltage provided, use an online led circuit calculator to make sure you have the right resistance for the voltage and your led types. If you’re doing this with the old or custom pendant, you can simply solder the leds to each other dead bug style shortly. It is ground, then hot glue them on or use a proto board for a nicer, looking circuit i’ll, be covering the whole back with some soft material. When i’m done to help protect the circuit and me once you’ve got your pendant soldered up measure out two equal pieces of your small gauge wire about three quarters of the length of your whole necklace solder them to each positive and ground of your pendant circuit. Then be sure to add lots of hot glue to your solder joints to keep them from breaking now. Attach your pendant to the necklace then carefully wind, the wire around the chain or cord loop it through or tie it at the top to make sure it doesn’t move around too much and you’ve got it now for the sensor.
First, we need to protect it. Squeeze a bit of hot glue onto the sensitive parts on the back, then squish it onto the sticky part backing of some masking tape or some paper. When it’s cooled simply peel. It off then add a bit more glue for wire strain relief.
Now take a little plastic circle guard and stick it to the front of your sensor. Now we can glue the metal ear clip to the sensor and then follow the guide on pullcensor.com to get their latest arduino code and upload it to the arduino. The default pull sensor sketch has everything we need built in, so you won’t need to change a thing to test plug in the red sensor: cable into five volts, the black one into ground, then the purple one to analog zero zero with power. The sensor should light up a bright, green wow, now put an led on ground and pin five, then press the sensor to your fingertip. If you get it positioned right, the led should flash to your heartbeat awesome, but how in the world can a little green light? See my heart beat and what is a heartbeat anyways now it’s time for smartbot’s thinking lab where we try to explain how things work. So what is a heartbeat in most creatures, there’s a heart wrong: heart, oops! Sorry, it’s this big pulsating lump of muscle that pumps this blood stuff everywhere in the body. Our blood helps carry stuff that our body needs. Oh here comes the inbound trunk.
Oh they’re, nice guys like nutrients oxygen and heat, go on you guys. You are great, it even helps move the bad stuff away cool. Then the nasty outbound like lactic acid, phosphates and carbon dioxide get out you get it bye, bye without our heart, moving everything around.
Oh, no, oh, no, i’m not feeling too well. We wouldn’t be alive, but your heart pumps faster when you’re scared or when you run around and play it’s really good to get exercise every day, because your heart has to work every single second every hour for the rest of your life. Even if you don’t it’s a good thing, we can measure how it’s doing. Try it out yourself just place two fingers on your radial artery on your wrist, in line with your thumb, apply a little pressure and you should feel it. What you’re feeling is a pressure wave as your heart pushes all the blood through thousands of little pipes throughout your body. It’S hard work count the pulses. You feel in 30 seconds double it, and you have your pulse rate.
A while ago. Some pretty smart guys figured out that if you shine a bright light at someone’s skin and watch how it reflects back, you can see that it gets brighter and darker depending on how the blood moves under the skin. If you look really closely at the front of the pool sensor, you can see a teeny weeny little light sensor. It’S sensitive enough to pick up tiny changes in reflected light when the blood flows through capillary tissue under the skin, though it doesn’t work so well on your wrist.
It works great on your fingers, earlobes and even the middle of your forehead work on working once you got your sensor tested it’s time, to put it all together for the lily pad. First, we change the analog input in the code to pin 5. next soldering ground and pin 11 from our led pendant leads, then cut off the jumper pins on our sensor tada and start around the power leads. Then the sensor lead to analog pad five.
But don’t forget the strength leaf hot glue to keep it up and out of the way i’m going to use an old hair clip and hot glue it to the back of the lily pad. Then we’ll use the little rechargeable battery that came with the lily pad. Tucked underneath to power, it all attach the sensor switch the power on the lily pad, and now i’m wearing my heart around my neck. That’S it, for this episode be sure to experiment with different uses for the sensor, take care of your heart and remember, get out there and make something you .