by Jason Poel Smith @ makezine.com:
When working in extreme temperatures it is important to monitor your body temperature. In freezing weather, your fingers and toes get numb and you can develop frostbite without even noticing it. Likewise, if your core body temperature drops too low, you can start to start to suffer the effects of hypothermia before you are aware of it.
So I designed an automatic temperature sensor that will monitor the temperature of your fingers, your toes, and your torso, as well as the outside temperature. This can help you to stay safe when working in extreme cold.
Wearable Temperature Sensors For Working in Extreme Cold - [Link]
Chas over at PNW/Electronics writes:
I came across a stash of iButton T-sense 1-wire sensors.. so I grabbed a couple and decided to check out 1-wire.
Maxim makes a 1-wire device called the DS18B20. It’s a 9-12 bit temperature sensor with the possibility of being powered by parasitic power from the data line. This cuts the signal path down to a single DQ line and a return. A company called iButtonLink produces a nice little wrapper around this device called a T-Sense. There are a couple pieces of software out there that will allow you to hook these up to monitoring systems, I don’t have any though. These devices come with a 64-bit address code and can be daisy-chained which makes having many of these devices monitored very nice.
iButtonLink T-Sense 1-wire sensor (Maxim DS18B20) + PIC 18F14K22 - [Link]
Davide Gironi published a new project an AVR ATmega328 based CO2, temperature and humidity logger and meter:
It logs data feed, CO2 in air in terms of ppm, temperature and humidity to a xively.com feed.
It also display realtime data to user through a 16×2 characters LCD.
This logger it is based on the xively logger you can found here
CO2 meter and Xively logger with NDIR infrared sensor built on AVR ATmega328 - [Link]
“Raz” over embedded-lab.com has written a tutorial on how to interface BMP180 temperature and barometric pressure sensor with Arduino UNO board. The BMP180 is a new generation sensor coming on a LGA package and it’s able to measure pressure in the range of 300 to 1100hPa using low power and achieving low noise measurements. The interface is a standard I2C and sensor is fully factory calibrated. The voltage required to power the IC is 3.3V, so your Arduino must provide 3.3V. On this tutorial the data is displayed on a 1.44″ TFT display and “Raz” moved a step further calculating the altitude from the derived pressure. Code and libraries are supplied on the link below.
Interfacing BMP180 temperature and pressure sensor on Arduino UNO - [Link]
The MCP6V01 auto-zeroed op-amp features an ultra low offset voltage (VOS) and high common mode rejection ratio (CMRR), which makes it applicable to temperature measurement. The MCP6V01 thermocouple auto-zeroed reference design demonstrates how to measure electromotive force (EMF) voltage at the cold junction of the thermocouple in order to accurately measure temperature at the hot junction.
The difference amplifier is implemented using the MCP6V01 and 0.1% tolerance resistors. It amplifies the EMF voltage at the cold junction of the thermocouple. The MCP9800 senses temperature at the type K thermocouple’s connector. It should be located as close as possible to the connector on the PCB. This measurement is used to perform cold junction compensation for the thermocouple measurement. The MCP1541 provides a VREF (4.1V) to the internal 10-Bit ADC of the PIC18F2550 and sets the reference voltage for the difference amplifier. The CVREF is the internal comparator voltage reference of PIC18F2550, which is a 16-tap resistor ladder network that provides a selectable reference voltage. The MCP6001 buffer amplifier eliminates the voltage reference output impedance problem and produces the voltage VSHIFT.
The 2nd order RC low-pass filter that is implemented in this circuit can remove the high frequency noise and aliasing at the ADC input. The ADC of PIC18F2550 completes the analog-to-digital conversion. The data will be transferred to the PC using the USB interface. The thermal management software on PC is used to perform data display to show the real-time temperature and apply cold junction compensation and data linearization to determine the actual temperature of the thermocouple’s hot junction (weld bead).
Thermocouple Auto-Zeroed Reference Design - [Link]
A smartphone add-on from Seek Thermal turns your smartphone into a thermal imaging camera. Retailing at $199 the Seek comes in two flavors; one plugs into the lower micro USB connector of an Android device and the other connects to Apple devices running iOS 7.0 or above, which is optimized for the iPhone and iPod touch. At its relatively low price it makes it possible to view temperature gradients and show real-time temperature values on screen that could only previously have been seen with the help of expensive thermal imaging equipment.
Smartphone Thermal Imager - [Link]
MUNICH — At Electronica last week, the LED manufacturer Everlight introduced what it claims to be the world’s first colour-temperature tunable LEDs in a simple chip on board (COB) package.
After brightness dimming, tunable color temperature is a feature that allows end users to tune the warmth of the light they receive. Typically, this feature is implemented through the use of multiple LEDs binned from cool white to warm white, behind a diffuser.
With its CHI3030 27V/29W series, Everlight claims to have a very compact solution, with LEDs packaged behind concentric layers of phosphors offering different color temperatures of white. Depending on how much warm white or cool white you choose to light up, you can get a precise color-temperature mix.
New LEDs offer tunable color temperature - [Link]
by Michael Mayes @ edn.com:
Although temperature is a fundamental aspect of our lives, it is difficult to measure accurately. Before the era of modern electronics, Galileo invented a rudimentary thermometer capable of detecting temperature changes. Two hundred years later, Seebeck discovered the thermocouple, a device capable of generating a voltage as a function of temperature gradients in dissimilar metals. Today, thermocouples as well as temperature dependent resistance elements (RTDs and thermistors) and semiconductor elements (diodes) are commonly used to electrically measure temperature. While methods for extracting temperature from these elements are well known, accurately measuring temperatures to better than 0.5ºC or 0.1ºC accuracy is challenging (see Figure 1).
Temperature-to-Bits converter helps solve challenges in sensor measurement - [Link]
I work as a software developer for a biology lab where my day job consists of creating applications to deal with big data visualisation. Recently however one of my colleagues had the need to take regular temperature measurements form a range of jars of liquids over quite an extended period. The commercial available solutions to achieve this are expensive and surprisingly lacking in features. So, as a dedicated hacker and maker, I immediately stepped in an said we could make something better ourselves. So we did. And this is how.
Quick & Easy Temperature Loggers - [Link]