As the team behind Amazon’s Echo frames began to improve the next generation of their product, they had to create a delicate balance. Customer feedback on previous versions of the Smart Audio glasses centered on three elements: winding of battery life, multiple style settings and improved sound quality.
Reaching all three of these goals would be a challenge in itself; To do so inside the slim form factor for a pair of Alexa-enabled glasses up ante.
“All three of these goals are in tension with each other,” says Adam Slaboski, Senior Manager for Product Management and Product Manager for Echo frames. The easiest way to improve battery and sound would be to increase the size of the device, but it would be in conflict with feedback about the importance of design. To amplify bass to improve the sound experience would consume more battery and so on.
Finding out that the sweet spot was a huge effort in technique and customer understanding.
“Finding out that Sweet Spot was a huge effort in engineering and customer understanding,” says Slaboski.
With Echo frames (3rd gen) and Carrera Smart Glasses with Alexa (designed in collaboration with Safilo, one of the world’s leading glasses), the Smart Eyewear team met the challenge.
The smart glasses have improved sound playback with custom-built speech processing technology that dramatically improves word recognition for interaction with Alexa in windy or noisy around. The new range of frameworks are available in different sizes, and all come with a significant boost in the life of the battery.
From the outside, echo frames still look like a pair of plain glasses. “But we changed everything on the inside,” says Jean Wang, general manager and director of Smart Eyewear. “And we learned new lessons along the way.”
Here’s how Amazon engineers and product designers tackled all three customer needs.
Turn up the volume with open ear sound
Like previous generations of echo frames, the current model uses open ear sound. In addition to mounting the form factor in a pair of glasses, this allows users to maintain attention to their surroundings while interacting with Alexa or enjoying sound entertainment.
The open ear-sound design has been popular with users who are blind or have low vision, notes Jenai Akina, senior product manager for Echo frames. “It’s really bone fish that it doesn’t prevent a critical sense like hearing,” she explains. “This form factor is really useful for daily interactions – especially when we had to be open to engaging in our surroundings and the people surround us. Open ear allows customers to maintenance awareness while giving access to a voice assistant.
Open-Ear Audio brings a number of unique challenges to the engineering process. Typical headphones and earplugs block the ear from the outside world and prevent air from escaping. To funnel more of the sound waves from the speaker into the user’s ears. With an open ear design, sound has been traveling far and there is less control over direction. It could lower sound volume and reduce clarity – and importers could sound out to people who are nearby. The key is to drive the sound press as much as possible towards the user’s ears while minimizing the sound leakage.
By bringing people into the laboratory, we can simulate real environmental noise conditions such as window, background noise in a crowded restaurant and the sound of cars on the road.
In the work of improving sound quality, the team continued to hone the direction of sound and also collaborated with improving volume and bass. A technique called DIPOL speaker configuration helps to do both. In addition to a healthy portthole loaded near the ear canal, the frames have another portthul that cancels unnecessary sound while it amplifies bass.
With input from internal audio experts and instruments for analyzing measurements such as harmonic distortion, Cam Cam Up with a set of potential setting solutions that set objective sound quality targets. They are tested these “taste” of tuning in the laboratory with several user groups.
“By bringing people into the laboratory, we can simulate real environmental clothing such as wind conditions, background noise in crowded restaurant and the sound of cars on the road,” explains senior manager for Audio Scott Choi. It allowed his team to understand environmental variables in a controlled framework.
With feedback from these focus groups, the team then chose a few of the most popular settings to push out to beta test where users could provide feedback on a weekly basis.
“We see how feedback tendencies change with each setting change, which gradually allows it to mature and converge to certain tuning,” says Choi. The result is audio-calibrated to maximize understandability and volume without leaking private conversations (or guilty Feet playlists).
To test the leak rigged the sound team up a rotating arc of microphones. The array moved in circles around a mannequin wearing the Gen 3 prototype and created a 3-D sphere of sound leakage plot. Choi explains that they focused on minimizing leaks to the side and back, and in the end the speakers were much closer to the ear to help minimize leakage and improve the volume.
Leakage is not the only confidentiality. The Echo Frame team also continues to innovate to protect users from bad actors who may get hold of their smart glasses.
Gen 2 protected users by requiring them to authenticate their sessions using a trusted phone. Without approval, a user cannot invoke sensitive commands such as “navigating me home” that unlocking Smart Lock or making in purchase. But customers didn’t like the extra friction.
Now, customers who sign up for Alexa Voice ID will be able to use their vocal fingerprints to approve to receive resorts to the pronunciation of smart homes.
“We are the first on-the-go Alexa device to use voice ID for privacy,” says Slaboski.
Increasing battery life without hugging style
Gen 3 improves continuous music play -time time to six hours against the four hours offered by the previous generation of echo frames. It also flows the life of the battery to up to 14 hours of moderate use spread across playback, talk time, messages and Alexa interactions.
Delivering the desired volume, bass and sound quality, while optimizing the life of the battery was a careful balance.
The team couldn’t just hit the larger battery without making the echo frames look less like normal glasses. And with sound quality high on the priority list as well, the units were Gooir that needed as much juice as ever. The team focused on trimming power use into standby mode, where the total battery consumption would fall without weakening the speakers when users needed them.
“To deliver the desired volume, bass and sound quality, while optimizing the life of the battery was a careful balance,” says senior product manager Ravi Sanapala. “We need the battery to last all day as possible and for Alexa to be available when users need it.”
The architectural changes in speaker location helped keep the power needs low while improving sound. The team also adjusted the location of the battery itself and distributed its capacity differently than in Gen 2. Sanapala adds that algorithmic changes were the key to balancing inactive battery conservation and on-demand device use.
“We had to collaborate with all our cross -functional teams to optimize everything,” says Sanapala.
Gen 3 also has a brand new charging stand designed for compatibility with all frame shapes and holding lentils vertically, protecting them from scratches while wireless charging.
Getting smart glasses looks like glasses
Making glasses that are followed for everyday wear has always been in priority. “One of our goals has always been to develop technology that appears when you need it and disappear when you do,” says Wang.
Previous models of echo frames have come in a single style of one size to suit everyone.
“It was very intentionally moving,” Wang explains. “We wanted to start simply and learn from customer feedback.”
Gen 2’s flexible spring hinge and adjustable temple tip ensured that each size fits many different faces. In fact, Wang says, while the goal was to fit about half of all potential users, they have found that 85 percent of the adult population can computers to wear the Gen 2 design.
But with Gen 3, Wang says, the team had to go beyond glasses that were typical. Customers wanted glasses that also looked stylish.
The team consulted both internal and external glasses designers to review ordinary and popular styles of frames, as well as “edgier” design and to explore potential customers about their preferences. After testing options with beta, they settled with different styles of different colors that cover aesthetics. They also switched to an acetate material to match the sensation of advanced eye clothing.
While each style still comes in a single size, the selection of designs will hold even more faces than 2 as the collection spans narrow, medium and wide passes. Each style has adjustable temple tips built of silicone around a light titanium core for better fit. And despite the boost in the life of the battery, the temples with Gen 3 frames have actually been slimmed down. Wang notes that competitive products often place large batteries behind a user’s ears. But presenting Ekko hits users with something that voluminous and uncomfortable was never on the table.
“We worked with really heavy limitations,” says Wang. “So we have been very conscious of making design choices in our customer’s service. It has challenged us to be innovative and really push the boundaries of what is possible in the architecture of our design. “