Praveen from CircuitsToday has written up an article on interfacing PIR sensor to 8051 microcontroller:
PIR sensors are widely used in motion detecting devices. This article is about interfacing a PIR sensor to 8051 microcontroller. A practical intruder alarm system using PIR sensor and 8051 microcontroller is also included at the end of this article. Before going in to the core of the article, let’s have a look at the PIR sensor and its working.
Interfacing PIR sensor to 8051 microcontroller – [Link]
by Susan Nordyk:
Novelda offers two noncontact sensor modules—one for monitoring respiration and the other for detecting human presence at a range of up to several meters— for use in home automation, sleep monitoring, baby monitoring, and elderly care applications. Both sensors employ the company’s XeThru technology, which uses radio waves to “see through” a variety of objects, including lightweight building materials and blankets.
The XeThru X2M200 sensor module for respiration monitoring measures both the rate and depth of breathing to allow breathing patterns to be tracked in real time. With a sensor range of 0.5 m to 2.5 m, the X2M200 provides a reliable but nonintrusive way to monitor respiration and movement, capturing breathing patterns and frequency without being blocked by blankets or other obstacles.
Noncontact sensors monitor respiration and movement – [Link]
PyroEDU began in 2012 with the mission of offering free online courses teaching the fundamentals of electrical engineering in an approachable and entertaining manner. Rather than studying textbooks and advanced mathematics, students are taught using a learn-by-doing approach that follows four basic steps: introduce the topic, explain the theory, build an experiment to demonstrate the theory, and offer real-world examples to demonstrate how the topic is utilized today. Students can interact with other students and the instructor via the PyroEDU forums or by joining one of PyroEDU’s hosted classrooms on uReddit or P2PU.
PyroEDU is currently teaching its sixth course, An Introduction to Sensors, covering a wide variety of sensors from motion detectors to temperature sensors. This sixth course is the capstone in the Introductory Series of courses PyroEDU offers (visit http://www.pyroelectro.com/edu/ for a complete listing of courses in the Introductory Series). Working with The Gadgetory, an online electronics retailer, PyroEDU will be offering a comprehensive kit that includes all the parts necessary to complete the Introductory Series of courses. More advanced series are planned in the future which may include courses in animatronics and robotics.
An introduction to sensors – [Link]
The TSL2584TSV from the Austrian company ams AG is a highly sensitive light-to-digital converter chip that converts light intensity into a digital signal output via its I2C interface. The chip sensors consist of one broadband photodiode (sensitive to visible plus infrared light) an infrared sensitive photodiode and a photopic infrared-blocking filter on a single CMOS IC. Two integrating ADCs convert the photodiode currents into a digital output that represents the irradiance measured by each sensor channel.
The digital output value can be used by an external processor where the illuminance (ambient light level) in lux can be derived using an empirical formula to approximate the sensitivity response of the eye. The TSL2584TSV can also generate an interrupt which remains asserted until cleared by firmware. The chip operates from a supply rail between 2.7 and 3.6 V and can handle a maximum light intensity of 33000 lux. The chip is packaged in a 6-pad TSV outline measuring just 1.66 x 1.145 x 0.32 mm.
A Tiny Light sensor – [Link]
Wireless, Credit-Card sized, Android + Linux + Arduino™, Embedded Sensors, starting from $49. What else?
UDOO Neo embodies a new concept: a single board computer suitable for the Post-PC era:
- Like a Raspberry Pi, you can program it in any language and run a full Linux environment with graphic interfaces.
- You get all the simplicity of an Arduino-compatible board, thanks to the Cortex-M4 and the Arduino UNO pinout layout, with the possibility of adding most Arduino™ shields, actuators and sensors, both analog and digital.
- An incredible, smoothly-running Android 4.4.3, it gives you the possibility to build new Android-based smart devices.
- You get a wireless module: Wi-Fi 802.11 b/g/n + BT 4.0 (Classic Bluetooth and Bluetooth Low Energy), because we hate cables.
- 9-axis motion sensors are embedded, to build your perfect drone/robot/3D printers/whatever or create new kinds of interactions with the real world.
- Open-source hardware: because we love to let you hack things or create new devices from scratch!
- Starting from $49!
UDOO Neo = Raspberry Pi + Arduino + Wi-Fi + BT 4.0 + Sensors – [Link]
by Steve Taranovich @ edn.com:
Gas sensing techniques are continually being investigated to improve selectivity and sensitivity of identifying different types of gases. There are resistive gas sensors, quartz crystal microbalance, direct thermoelectric, electrochemical cell and other exotic types such as MEMS-tunable Fabry-Perot filter spectral sensors with lead-selenide detector and pulsed broadband infrared emitter light source. The ams sensor is a resistive type.
The resistive sensor design relies upon heating circuitry for temperature control of the entire system. There are different types of resistive gas sensor techniques and construction. Some are based upon metal-oxide (MOX) thin films which are small in size, low-cost, and low power as well as able to use low-power integrated analog front ends.
ams develops MEMS VOC gas sensor – [Link]
by Mahesh Venkitachalam:
I was in Bhutan last December, and as we travelled to different locations, I kept wondering what the temperature and altitude was, and wished I had some gizmo that would show me these values. Back home, I did a bit of research on altitude sensors, and one that came up was the cheap BMP180 sensor. It measures temperature and pressure, and the latter can be used to calculate the altitude. It’s been lying around with me the past few months, and now I’ve finally gotten around to building a display around it.
Temperature / Altitude / Pressure Display using BMP180 – [Link]
TCS3490 intelligent color sensor’s accurate measurement of color temperature and ambient light intensity enables sophisticated display color management control for smartphones, tablets, notebooks and digital still cameras
ams AG released the TCS3490, a color sensor for portable devices which is ideally suited for light source detection when operating under a wide range of light sources.
Providing accurate color and light intensity measurements, the TCS3490 enables designers of portable devices such as smartphones and tablets to implement more sophisticated display management and brightness control.
This integrated five-channel color sensor has extremely accurate measurements of the Correlated Color Temperature (CCT) of light. As sensors continue to proliferate in today’s mobile electronics market, manufacturers of mobile devices such as smartphones, tablets and laptops can use these measurements to dynamically adapt the display’s color palette to provide the user with a superior viewing experience.
AMS color sensor for mobile devices improves accuracy and offers new light source detection capability – [Link]
Motion sensing is the detection of the change in position of an object relative to its surroundings or vice versa. There are many kinds of motion detector methods: infrared, optics, radio frequency, sound, vibration, and magnetism. These methods differ from each other because each of them uses a different medium and detects different subject (e.g. sound: in Doppler effect, motion is detected by the change in reflected frequency).This project uses PIR (passive infrared) sensor to detect the change in radiation, this can be use on lighting control, temperature control, and motion detection since all objects with temperature above absolute zero emits heat energy in the form of radiation. The term passive refers to the fact that PIR devices do not generate or radiate any energy for detection purposes. It works entirely by detecting the energy given off by other objects.The D204B PIR sensor is used in this project, it contains a material that generates energy when exposed to heat/radiation. The MCP6H94 quad op-amp is used in two stages; amplifier and comparator. The weak signal from the PIR sensor will be amplified by the first two op-amp configured as amplifiers, the amplified signal is then fed to the last two op-amp configured as comparator. The BC548 NPN transistor acting as the switch will be triggered when the comparator’s output gets HIGH, further, switching the transistor will also trigger the relay that is connected to the load (light and/or alarm).
PIR Motion Sensor – [Link]
While trying to create a circuit that detects whether water is flowing through a pipe by measuring the vibration with a piezoelectric sensor, just to see what happens I taped the sensor around my finger and – to my surprise – got values that were a very noise-free representation of my heart rate!
Measuring Heart Rate With A Piezo – [Link]