MADISON, Wis. — Hillcrest Labs has just snatched a smartphone design win for its sensor hub software from Coolpad, China's mobile device supplier. This development illustrates the insatiable appetite among smartphone and wearable vendors to add more sensors to their devices. However, they're also looking for ways to manage the proliferation of sensors inside a system.
Hillcrest's sensor hub software products are designed to combine an array of algorithms to provide low power and high-performance sensor fusion while transforming sensor data into app-ready information, according to the company.
In Coolpad's sensor hub implementation, Hillcrest's software runs on Atmel's low-power microcontroller. By offloading sensor management from the smartphone's main processor, the software will “dramatically lower power consumption and extended battery life,” Hillcrest said in a press release.
The deal with Coolpad is the second major victory in Asia for Hillcrest's smartphone software. In February, Hillcrest announced that China's Oppo is using Freespace to enable intuitive gesture recognition.
The implementation of the sensor hub inside Coolpad's new smartphone includes an accelerometer, a magnetometer, and a gyroscope. However, a Hillcrest spokeswoman told us the hubs can handle several additional motion and environmental sensors — such as pressure, humidity, and ambient light (ALS) — if OEM partners choose to use them.
Chad Lucien, senior vice president of sales and marketing at Hillcrest, said in the release that sensors can bring many potential differentiators to mobile devices. Typically, they enable context awareness, augmented reality, improved navigation, and better gaming.
In the deal with Coolpad, Hillcrest's sensor hub software offers both lower power consumption and higher motion tracking performance.
More specifically, the spokeswoman said, from an application standpoint, Coolpad can provide users with such advantages as “accurate health and fitness monitoring (fewer false positives in step counting, accurate detection of walking vs. running, etc.), 24/7, without compromising battery life,” along with “precise augmented and virtual reality application motion tracking.” They can also offer “accurate mapping and navigation through improved heading/compass accuracy.”
Varying sensor hub implementations
Hillcrest isn't alone in offering sensor hubs. Among the many different approaches being taken to implement sensor hubs, Hillcrest is using a separate processing element to manage sensor functions on the phone.
The term “sensor hub” suggests the use of a low-power microcontroller (MCU) dedicated to sensor management functions. Depending on the specific MCU chosen, the level of functions it can offer varies, ranging from basic sensor calibration and sensor fusion to advanced application-level data processing to support activity monitoring, context awareness, and pedestrian navigation.
Several low-power MCU cores have been used as hub processors. Atmel's MCU has been used for a number of the early smartphone hubs. More recently, a number of ARM Cortex M0+ cores have reportedly been used. As hubs add more functionality, low-powered ARM Cortex M4 cores are reportedly being considered.
In any case, the advantage of using a separate processing element for a sensor hub is clear. It lets designers customize the processor and sensors, which “makes this a powerful and flexible approach to enable a wide range of sensor-based features,” the Hillcrest spokeswoman said.
Another approach — one often taken by sensor vendors — integrates processing with the sensors themselves.