The new batch of Cornell University ECE 4760 Final Project are in! There are tons of cool projects as usual, everything from Human Tetris to this MIDI Glove Controller project by Anson Dorsey, Eric Gunther and Jonathon Smythe. The project is based around an Atmel Mega644 microcontroller which has lots of processing capability and all of the projects are developed in WINAVR/GCC. Since the system is outputting MIDI you are able to play any instrument sound you want, I was looking forward to barking dogs or meowing cats but the piano and drum demonstration was great too.

Thanks to Bruce Land for all of the behind the scenes inspiration for these cool projects!

“We attached a piezoelectric vibration sensor to each of 8 fingers on a pair of leather driving gloves. The gloves are attached to a microcontroller which processes the taps and outputs MIDI signals via a standard MIDI output port. Additionally, the user can select a variety of note mapping schemes and presets for the gloves via a user interface in MATLAB. Our budgetary limitations forced us to choose a sensor that was sub-optimal for our needs. The inexpensive flex sensors we chose are designed to sense vibrations, not pressure touch; they sense differential flex, so the output voltage level is directly proportional to how fast the sensor tab flexes. As a result, we had to compensate for the sensor output by performing a kind of integration in software. Memory was not a huge concern for us, so we were able to initialize several arrays to track the prior states of the sensors. However, state-tracking introduces an inherent latency to our project; for every prior state we tracked, 1ms of latency was added to the time it took for an action to turn into a MIDI message.”

If you need to do some temperature monitoring over a long period of time this is the device for you. It can store 32 thousand measurements and has a current draw of only 50uA. The top picture is version 1 and below is a shot of the surface mount version 2.

Via: Electronics Lab

“The PIC software is written in assembler and based on earlier projects using I2C interfaces. The EEPROM, PIC and external connector all share the same I2C bus and the PIC will not use it unless the thermistor is fitted. The EEPROM address keeps incrementing in this case so that breaks in the data can be seen.

When the temperature measurement is not being made the PIC goes to sleep. It is woken once a second (using an external crystal oscillator and internal counter) to check if it is time to make a measurement. The sampling interval is stored in a fixed location in the external EEPROM and is read at power up.

The thermistor and a resistor form a potential divider that is measured by one of the ADC channels on the PIC. This is measured four times and the four results are added together. This gives a slightly better measurement since the average of four readings is likely to be closer to the true value than a single measurement alone due to the noise present in the circuit.“

So you think your meter is tough do you? Dave Jones of the EEVblog took a few cheap and a few high quality meters and subjected them to some high energy discharges. If may have seen a component let out its magic smoke but it is something else to see a meter literally blow apart. This destruction is all thanks to a machine that Doug Ford built.

Laser harps seem to be catching on. This one is a work in progress and believe it or not there is no microcontroller or computer controlling the system. For more information have a look at the project page (translated version).

“This is my first video showing the sensor-circuit working, that contains 4 opamps (LM358) and only has a +5V supply (no negative supply). You can understand it’s a challenge to get it working! But it does work!“

Our friend Csaba Bleuer sent in this crazy project he completed. It is a Rotating LED Globe which is being driven by a ATMega Microcontroller. The globe image was created using a program called BmpToAscii, with this program an image can be converted into Ascii. In this case the Ascii is used to display the globe! We have seen some other spinning LED globes in the past but this one by Csaba seems very smooth in operation. There is a hand drawn schematic below and if you are interested in digging deeper into the detail have a look at the code that Csaba was kind enough to share with us.

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DIY medical equipment is not a big hobby area but this DIY Pulse Oximeter is one cool device. I have no idea what a commercial Pulse Oximeter but like anything medical the real stuff that is used in hospitals usually costs big bucks. In this case your finger is slipped between two pieces of medical grade oak to take the reading.  The project is based around the powerful 68HC908AB32 microcontroller.

Thanks Maciek

“A pulse oximeter is a medical device that indirectly measures the oxygen saturation of a patient’s blood (as opposed to measuring oxygen saturation directly through a blood sample) and changes in blood volume in the skin, producing a photoplethysmograph. It is often attached to a medical monitor so staff can see a patient’s oxygenation at all times.”

We often keep important data or personal information on devices that we feel is secure. Well think again. Even though these phones that Will O’Brien picked up had their personal messages locked by PIN simple plugging in a serial cable allowed the messages to be pulled right out.

“Hooking up the serial port is just a matter of connecting a 3/32″ audio connector up to a TTL USB serial cable. I was pretty amused by the two hundred SMS messages that were left inside the phones memory. I used a fake – phone number in these samples. Here’s an interesting bit: the phone actually had a pin on the messaging screen! Even without the pin I was able to pull the text messages off the phone.”