Intel Engineer Reimagines Earbuds for Smartphones
Published on: 20th Jan 2014
By: Ian Mansfield
When she literally jogged on stage to join Intel CEO Brian Krzanich in his opening keynote at International CES in Las Vegas engineer Indira Negi was there to demonstrate the Intel smart earbuds that she and her team had developed but the "smart" design she showed off also helped solve an issue the avid runner had personally encountered.
"I am a runner - I get hives from the sun, I have to run with gloves on," said Negi about running with a smartphone. "That means when there is a bad song, I have to take out my phone, take off my gloves, unlock my phone and change the song."
Starting from solving a problem that she knew all too well, Negi, a sensors systems engineer in the Intel New Devices Group, and a team set out to create a device and software that would monitor heart rate and adjust music playback based on sensor feedback. The result was the Intel smart earbuds reference design, developed in collaboration with Valencell.
Negi's study of bioelectronics and biosensors in graduate school - she earned a master's degree in electrical engineering from Arizona State - lent her a keen appreciation of the value of biometric monitoring.
One project she worked on while at ASU measured stress levels in saliva using specially treated paper. When you are working out, you are stressing your body in a positive way, explained Negi. If you work out too hard, this becomes negative stress, which can increase the chances of getting injured. She also worked on molecular imprinted polymers while at ASU coated with biochemical sensors that reacted only to specific molecules.
"It was only in grad school that I found my passion for bio-sensing
electronic devices," said Negi. "I was lucky."
A Maker at Heart
Though she has a zeal for bio-sensing technology, Negi also enjoys building on a larger scale.
"It's de-stressing for me to work with my hands," said Negi, who built her own furniture while in graduate school. "I made a table, a bookshelf and a really wobbly chair."
And she's not just a furniture maker. When Negi noticed that the holiday lights hung in her backyard had been chewed by squirrels, she created what she calls a "squirrel chaser."
"I didn't want to kill the squirrels," said Negi. "I just don't want them in my yard."
Built using an infrared sensor, servo motor, buzzer, Tupperware and an Arduino board, the device watches for squirrels. When it detects motion, the squirrel chaser makes a loud noise (the buzzer) and the servo motor waves a flag. Negi said she plans to add a camera to her invention to capture the squirrels in the act.
Negi is also building a fountain in her backyard and likes to sew and paint. She doesn't distinguish between her different maker projects or put much stock in gender-based stereotypes about activities.
"I don't know why certain things are supposed to be men-tasks or
women-tasks because in my head, they are all the same," she said. "You are
"Smart" Biometric Projects
The Intel smart earbuds reference design that Negi and the team developed aren't the only project she's worked on that used biometric sensors. One research project integrated sensors directly into a smartphone.
"People use their phone all of the time," said Negi. "We want to make all of the sensing opportunistic. We wanted it to happen incidentally. We wanted for it to happen on its own."
That research project led to her work on the Intel smart earbuds, which actively monitor heart rate via sensors and can be integrated with smartphone applications to provide additional functionality like helping to choose music.
Originally, the smart earbuds were designed to work with Intel-powered phone, but then the team changed direction.
"We wanted it to work with every phone," said Negi. "That was a much harder problem because all of the connectors were already used."
A typical headset has four standard connectors, left audio, right audio, microphone and ground. The team didn't want to use Bluetooth, but instead worked on a wired earbud design.
"[A wired earbud] doesn't need power, doesn't need to be charged, doesn't need to be paired," said Negi. "It's always ready to go."
The Intel smart earbuds harvest energy from the smartphone microphone jack, which was challenging because of the limited power envelope and the need to use the same port for both power and data.
"We had a lot of very interesting electrical engineering problems to solve," said Negi.
All of the processing is done on the smartphone. The earbuds simply transmit the raw data captured by its sensors to the smartphone for analysis and processing. An infrared optical sensor looks at the pulsing of the skin within the ear.
"Ears are a good place [for sensors]," said Negi, "because there is no other motion that can be created."
The accelerometer in the earbuds is designed to correct for motions such as shaking one's head. It's simple to calculate heart rate if you are not moving, according to Negi, but you need the accelerometer to decipher heart rate when a person is active.
Because the Intel smart earbuds reference design are single function, Negi doesn't consider them part of the Internet of Things until they are connected to a smartphone, but counts the need to connect them as a plus because it's familiar.
"It is a wearable that you have no resistance against because you already use them," she said.