“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]
A simplified explanation of how a capacitive MEMS accelerometer works.
How an accelerometer works! - [Link]
by Amy Norcross @ edn.com:
A team of University Wisconsin-Madison researchers, with support from the Defense Advanced Research Projects Agency’s (DARPA’s) Reliable Neural-Interface Technology (RE-NET) program, have developed “invisible” implantable medical sensor arrays that will not block views of brain activity. Their research was published in the Oct. 20 issue of Nature Communications.
According to a recent Phys.org article, “electrical monitoring and stimulation of neuronal signaling is a mainstay technique for studying brain function, while emerging optical techniques—which use photons instead of electrons—are opening new opportunities for visualizing neural network structure and exploring brain functions. Electrical and optical techniques offer distinct and complementary advantages that, if used together, could offer profound benefits for studying the brain at high resolution. Combining these technologies is challenging, however, because conventional metal electrode technologies are too thick (>500 nm) to be transparent to light, making them incompatible with many optical approaches.”
Implantable, transparent sensors give researchers a better view of brain activity - [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]
by Nick Lavars:
While the stench of rotting food would cause you to stop from chowing down, chances are it became unfit for consumption some time before those funky aromas wafted through your nostrils. Chemists at MIT have been working on a wireless, inexpensive sensor that, among other things, identifies spoiled food early by detecting gases in the air. It then shares its data with a smartphone, potentially alerting users to that soon-to-be moldy fruit in the bottom of the fridge.
Wireless sensor alerts your smartphone as food begins to spoil - [Link]
praveen @ circuitstoday.com:
This article is about interfacing gyroscope to arduino. Gyroscope is a device used for measuring the angular velocity in the three axes. It works under the concepts of angular momentum and can be used to determine the orientation of an object. Typical applications of gyroscope includes missile guidance, flight control, smart phones, game station joy sticks etc. Mechanical gyroscopes, MEMS gyroscope, optic fiber gyroscope, ring laser gyroscope.
Interfacing gyroscope to arduino - [Link]
by noelportugal @ instructables.com:
The day I read that a new $5 wifi module was available, I order a few of them to test. Now, a few weeks later I want to share my experience.
This is a very simple demo using the ESP8266 and Arduino to update a remote server (https://thingspeak.com/) using a digital temperature sensor.
ESP8266 Wifi Temperature Logger - [Link]
The LTC2983 measures a wide variety of temperature sensors and digitally outputs the result, in °C or °F, with 0.1°C accuracy and 0.001°C resolution. The LTC2983 can measure the temperature of virtually all standard (type B, E, J, K, N, S, R, T) or custom thermocouples, automatically compensate for cold junction temperatures and linearize the results. The device can also measure temperature with standard 2-, 3-, or 4-wire RTDs, thermistors, and diodes. It has 20 reconfigurable analog inputs enabling many sensor connections and configuration options. The LTC2983 includes excitation current sources and fault detection circuitry appropriate for each type of temperature sensor. The LTC2983 allows direct interfacing to ground referenced sensors without the need for level shifters, negative supply voltages, or external amplifiers. All signals are buffered and simultaneously digitized with three high accuracy, 24-bit ΔΣ ADC’s, driven by an internal 10ppm/°C (maximum) reference.
LTC2983 – Multi-Sensor High Accuracy Digital Temperature Measurement System - [Link]