Hypoglycaemia is a condition characterized by an abnormally low level of glucose in blood. It is associated with diabetes, and is likely to occur if someone with diabetes takes too much insulin, eats less than usual, or exercises too hard. Novirium‘s Nighttime Hypoglycaemia monitor is a bluetooth-enabled device that acts as a safety net for type 1 diabetics, while they’re sleeping. The nighttime hypoglycemia results in excessive sweating. This monitor measures the skin temperature and humidity to detect severe nocturnal hypoglycaemic events. Measurements are taken periodically and are sent to a nearby Android phone via Bluetooth. If such an event is detected, a list of emergency contacts are called for assistance.
Nighttime hypoglycemia monitor
A mobile sensor device contains an ATmega328p, an HIH6131 humidity and temperature sensor, a LIS3LV accelerometer and a SPBT2632C2A Bluetooth module, all powered by a 2.7V LTC4081 switchmode power supply/charger and a 400mAh LiPo battery. The sensor is designed to be worn close to the skin of the diabetic, and detect the heavy sweating that often occurs with very low blood glucose levels.
Every 15 minutes, the sensor module powers up the Buetooth module and connects to the nearby Android phone, uploading all the sensor data for that period before switching the Bluetooth back off to save power. The Android application then sorts through this data, and determines if an alarm is required. If an alarm is triggered, it then works through a list of preset contacts, calling them for assistance until one texts back.
Electro-Labs has posted a new project about making a DIY USB power meter based on Atmega328 processor. It sits between the USB port of the computer and the USB device to be connected to monitor the USB output supply voltage and the current drawn by the USB load device. The computed power consumption is displayed on a small OLED on the board. The USB meter stick itself gets powered from the USB port.
DIY USB power meter stick
The board is built around an Atmel ATMEGA328 microcontroller. To make the circuit as small as possible, the MCU is used in minimal configuration. Internal 8MHz oscillator is used. The voltage and the current are measured by the internal 10 bit ADC. To make the measurements more accurate, an external 2.5V voltage reference IC, Microchip MCP1525 is included. The current is converted to voltage on a 0.01R sense resistor and precisely amplified by LT6106 before read. The stick can measure up to 2.5A. Since the OLED display requires 3.3V supply voltage, L78L33ACUTR linear voltage regulator is used for 5V to 3.3V conversion.
This garage door opener built around the parts mostly available from Sparkfun uses the fingerprint scanning mechanism to open the door.
Garage door opener with fingerprint scanner
As a person without a car, I don’t need to carry keys around everywhere I go. Because of this, I’ve been locked out of my own house several times. It’s a pain to wait for someone with a key, so I thought I would do something about it.
This project is my way of solving this problem, while getting the chance to interface with an awesome fingerprint scanner (aka: FPS).
Also, this module isn’t restricted to just garage doors, for you can create different kinds of simple motorized locks to suit your needs.
Designed by Nick, a BSEE student at Oakland University, ChronosMega is an Atmega328-based wrist watch that is battery-powered (3.7V rechargeable Li-Ion) and displays time (hours and minutes) in binary format using 10 LEDs. The LEDs are arranged in a special circular pattern, where the four LEDs in upper half circle displays hours and the remaining six LEDs in the lower half circle display minute. The watch also contains an USB charger onboard, which uses Microchip’s MCP73831 charge management controller IC. There are four tact switches for user interface that controls the time setting, display, and sleep mode operation. Time keeping is performed using the 8-bit Timer2 module of Atmega328, which is programmed to count 10th of a second asynchronously from the system. For precise Timer2 operation, a 32.768 kHz crystal is used for the XTAL pins of Atmega328.
ChronosMega: A DIY LED wrist watch
The Serial Monitor application embedded into the Arduino IDE is a very useful tool in developing Arduino applications. In addition to its normal use for sending/receiving data bytes over the Arduino serial link, the Serial Monitor tool is extensively used for diagnostic or debugging purpose by serially printing out the intermediate values of the program variables during various steps of execution. The drawback of this debugging approach is you need access to computer for using the Arduino Serial Monitor or any other serial terminal program. ARPix has posted this instructable on constructing an external serial monitor device using the Atmega328 MCU and a graphic LCD. It allows a user interface to set the serial baud rate and start/stop functions using tact switches.
External serial monitor for testing/debugging