While it can be difficult to get enough sleep, at least you can try to make it as restful as possible when you are in bed. That’s the idea behind this project by Julia Currie and Nicholas Sarkis, who developed an Arduino Nano-based sleep monitor for their final ECE 4760 project at Cornell.

The bulk of the monitoring device takes the form of a glove which measures heart rate using an IR sensor, along with movement via an accelerometer. Breathing is recorded using a conductive band wrapped around the user’s chest, which changes resistance depending on how it is stretched.

The Nano mounted to the glove collects this information, and transmits it wirelessly using an nRF24L01 chip to a PIC32 microprocessor on a base station. Data is then graphed nicely on a TFT display for further analysis.

You can read more about the project here and see the video below!

There’s a lot more to learning how to play the guitar than just playing the right notes at the right time and in the right order. To produce any sound at all requires learning how to do completely different things with your hands simultaneously, unless maybe you’re a direct descendant of Eddie Van Halen and thus born to do hammer ons. There’s a bunch of other stuff that comes with the territory, like stringing the thing, tuning it, and storing it properly, all of which can be frustrating and discouraging to new players. Add in the calluses, and it’s no wonder people like Guitar Hero so much.

[Jake] and [Jonah] have found a way to bridge the gap between pushing candy colored buttons and developing fireproof calluses and enough grip strength to crush a tin can. For their final project in [Bruce Land]’s embedded microcontroller design class, they made a guitar video game and a controller that’s much closer to the experience of actually playing a guitar. Whether you’re learning to play for real or just want to have fun, the game is a good introduction to the coordination required to make more than just noise.

In an interesting departure from standard stringed instrument construction, plucking is isolated from fretting.  The player fingers notes on four strings but plucks a special, fifth string with a conductive pick that closes the plucking circuit. By contrast, the fretting strings are normally high. When pressed, they contact the foil-covered fingerboard and the circuit goes low. All five strings are made of carbon-impregnated elastic and wrapped with 30AWG copper wire.

All five strings connect to an Arduino UNO and then a laptop. The laptop sends the signal to a Bluefruit friend to change Bluetooth to UART in order to satisfy the PIC32. From there, it goes out via 2-channel DAC to a pair of PC speakers. One channel has the string tones, which are generated by Karplus-Strong. To fill out the sound, the other DAC channel carries undertones for each note, which are produced by sine tables and direct digital synthesis. There’s no cover charge; just click past the break to check it out.

If you’d like to get into playing, but don’t want to spend a lot of money to get started, don’t pass up those $30-$40 acoustics for kids, or even a $25 ukulele from a toy store. You could wind your own pickup and go electric, or add a percussive solenoid to keep the beat.

A while back I notice the simularity between the Ultrasound/IR sensors we use on robots for object avoidance to the concept of basic RADAR. (This is more like UDAR or IRDAR). Direction and range information are what the controller uses to detect objects (RADARs basically use the same information.)

So instead of building robots for a while I decided to see how good I could make my own IRDAR. Wow! One can adjust trigger point, gain and a bunch of other factors and have a way-cool little system!

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