User Interface (UI) is on the verge of a major shakeup as it was evident at the Mobile World Congress (MWC) this year. Leaving behind other UI interfaces such as motion, touch, and voice, touch-less is now looming large and lucrative as the new UI of choice for consumer devices. Touch-less means you can operate your device simply by waving your hands near it, without actually touching it.
The CEO of Chirp Microsystems, Michelle Kiang is of the opinion that the UI revolution has been bringing on constant consumer electronics breakthroughs. Chirp is offering a single-chip sensor working as a time-of-flight (ToF) ultrasonic unit, to allow users to interact with wearable devices even without actually touching their screens, or interacting with devices that work without screens.
Although the touch-less technology, based on ultrasonic sensing, is not yet ready to replace other existing UIs, Kiang is of the view that it will certainly add another level of modality to automotive, smartphones, AR/VR, and wearables.
Chirp Microsystems is a startup from Berkeley, California, with a UC Berkeley and Davis heritage. At the MWC, they presented the company’s first high-accuracy ultrasonic sensing development platform. As they have especially targeted the platform for wearables, it has ultra-low power consumption. The breakthrough by the team of engineers and researchers at the University of Berkeley and Davis—miniaturization of the MEMS-based ultrasonic sensor—formed the foundation of the startup.
According to Kiang, most smartwatches and other wearables suffer from small screen sizes that have limited surface, and do not work well with fat fingers. The MEMS-based ToF ultrasonic sensors embedded inside the smartwatch helps users with any type of fingers to use gestures. They can control the functions of the watch, even without touching the screen.
For instance, the wearable wristband has no space for a screen on it. That makes it powerless to interface with its wearer directly. However, the ToF ultrasonic sensor is tiny enough to be embedded within the band or even in a ring. Now, all popular wearable bands can interact with their wearers.
The ToF ultrasonic sensor from Chirp comes in a 3.5 mm package called Land Grid Array (LGA). According to the company, the chip operates on a 1.8 V supply, and is similar to a MEMS based microphone. Integration into consumer electronics products is simple, as the IC has an I2C interface.
Along with the MEMS ultrasound transducer, Chirp has also developed an accompanying mixed-signal CMOS ASIC. Then they combined both into a system-in-package, making it easier to use.
The on-board microprocessor with the ToF sensor works in an always-on mode for applications requiring wake-up sensing. According to the company, the pulse-echo sensing range is greater than a meter, but consumes only 9 µA, working at 1 Hz sampling rate.
After the transfer of the IP and the key researchers from the University to Chirp, including David Horsley, several PhD students and postdocs from the University have also joined Chirp. David Horsley was a professor at the University of California and Davis, in the department of mechanical and aerospace engineering, and is now the CIO at Chirp Microsystems.