Control an LED with your breathe

---

This Arduino radar lets you control the brightness of an LED with your breath.

---

A few months ago, Norwegian sensor developer Novelda unveiled a pair of adaptive Atmel | SMART ATSAM4E16E powered sensor modules capable of monitoring human presence, respiration and other vital information in real-time. Based on the company’s XeThru technology, they use radio waves rather than infrared, ultrasound or light, enabling them to ‘see through’ an assortment of objects ranging from lightweight building materials to blankets. These modules can even be employed to detect movement in a room, as well as measure the breath of a person, without contact.

With one of these boards on hand, Maker Øyvind Dahl decided to build an Arduino radar that could control the brightness of an LED with his breath. To accomplish this, he hooked the X2M200 respiration monitoring sensor up to an Arduino Uno (ATmega328). The module, which was tasked with detecting his chest movement, also required both a USB communication board and a level shifter to interface the 2.8V levels of the XeThru with the 5V of the Uno.

Dahl connected an RGB LED to the project, whose brightness faded in unison with his breathing. When he inhales, the light fades in. And when he exhales, it fades out. Beyond that, the faster that he breathes, the faster the LED will fade.

In order to make this work, the Maker wrote his own code for the radar — which can be found on GitHub here — that would would send over the respiration data.

“Another thing I was struggling with, was type conversion. And with only an RGB LED as my output, it was a bit hard to debug,” he explains. “So I connected another Arduino with SPI, that I could use as a debugging console for a while, and got the type conversion sorted out. I parsed the data that was coming in, and used the movement-value to set the brightness of the LED.”

Since the Arduino did not process the data quick enough, Dahl ended up adding a function to his code that would empty the buffer and sync the data each time that he fetched a new measurement.

While this is merely a prototype, there’s plenty of potential for development. Dahl says that upon completion of his “useful device,” he will share the code and detailed breakdown of the project on his site. As we await to see what the Maker comes up with, you can find his first tutorial here.

These sensors can monitor breathing and detect presence through walls

---

Novelda introduces a pair of new sensor modules for detecting human presence and monitoring respiration.

---

Norwegian sensor developer Novelda has launched a pair of adaptive smart sensor modules that are capable of monitoring human presence, respiration and other vital information. Based on the company’s proprietary XeThru technology, the unobtrusive sensors can detect presence from chest movement, as well as rate and depth of breathing, allowing patterns to be tracked in real-time.

This is because XeThru technology uses radio waves rather than infrared, ultrasound or light, which enables the Atmel | SMART ATSAM4E16E based modules to ‘see through’ an assortment of objects, like lightweight building materials, duvets and blankets, to provide non-contact sensing at a range of up to nearly five meters. Impressively, each module consumes less than 400mW power and remains unaffected by dust, smoke, moisture, darkness or any other airborne debris it may encounter.

“A vast number of sensors and sensor technologies exist today, the most common being IR, capacitive, ultrasonic, and microwaves. Due to the strengths and weaknesses of different technologies, sensors are typically designed for only one task, such as detecting presence, motion, speed or distance. This is typically at one defined range or at very short range, or only on moving or static objects, and so forth,” the team explains. “In applications where you want to combine features from several sensor technologies and/or hide your sensor due to security or other design constraints, your options are limited. This is why we set out to develop our XeThru technology and gave it the abilities it has today.”

First, the XeThru X2M300 module is intended for smart home automation where its capability for detecting human presence while being integrated into a building’s structure enables hidden, tamper-proof sensing. Aside from security and comfort applications, such as the convenient actuation of lighting and environmental controls, this SoC can enhance safety throughout the house — especially for the elderly or those living alone, using the absence of normal activity to raise an alarm. To get started, users simply affix the sensor with its main sensitivity direction pointing toward the area to monitor.

Meanwhile, the X2M200 sensor module is designed for respiration monitoring of people of all ages for health and well-being purposes, especially for sleep improvement systems and spotting nighttime abnomralities. XeThru’s non-contact technology offers a reliable yet non-intrusive way to observe respiration and movement, capturing breathing patterns and frequency without being blocked by blankets or other obstacles during a slumber.

Novelda has also launched a XeThru Inspiration Kit — an easy-to-use, hardware and software platform that includes the pair of sensor modules and interface boards for PC connection. This provides developers with a simple way to devise working proof-of-concepts and carry out the prototyping process. The XTIK1 gives users all the necessary tools to evaluate the performance of the sensors using the supplied software that supports module configuration, visualization of sensor data and the ability to record data for further analysis.

Beyond that, the kit comes with XeThru’s Explorer software and a programmer unit should the firmware need to be updated. In which case, a JTAG programming interface available on the USB communication board is used to upgrade the program running in the module along with an Atmel-ICE programming probe. The probe connects to the PC via USB, while a ribbon cable connects from the Atmel ICE SAM port to the 10-pin connector on the USB communication board. As Novelda notes, the procedure requires the download and installation of Atmel Studio.

Intrigued? You can head over to its official page to make more ‘sense’ of the topic.