The first MEMS accelerometers in iPhones and the Wii revolutionized the user interface by introducing natural motion as an input mechanism, but it's taken a while for designers to figure out how best to use these capabilities. Now the inertial sensors are starting to move into a wider range of motion control and precision location applications, helped along by lower costs, and by the generally maturing of the knowledge base and infrastructure that are making the sensor data easier to use.
Yole Développement projects these developments will drive accelerometers and magnetometers to be designed in to close to 50 percent of all mobile phones within five years, and gyroscopes to be included in some 20 percent, mostly at the higher-end smart phone part of the market. Gyroscopes are already in almost all tablets, mostly because Apple still so dominates that market with better than 90 percent share. We expect usage of inertial sensors in consumer electronics will increase by about 24 percent on average annually for the next five years, to reach some 5 billion individual sensor units by 2015.
Lower prices and better software and infrastructure help drive adoption
Major applications for inertial sensors outside of games so far have actually been somewhat limited. Accelerometers have become a must-have in mobile phones for switching between portrait and landscape mode, and seen scattered use in pedometer functions. Magnetometers hit mass adoption in phones last year, to supply correct heading for navigation. Multiaxis MEMS gyroscopes have just reached consumer price points and volumes and are showing up in first phones and essentially all tablets, although initially largely for games.
But lower prices are helping drive wider adoption. Yole sees costs of discrete inertial devices continuing their steep decline, with the ASP of a three-axis accelerometer, for example, dropping from $0.70 in 2010 to around $0.30 by 2015—or less than $0.10 per axis. Part of these cost savings will be driven by sharing the cost of one controller ASIC between two sensor devices, by packaging the accelerometer and the magnetometer, or the accelerometer and gyroscope together as one combination sensor with one ASIC. This can also improve the sensor data, directly building in the corrections of each sensor for the deviations of the other.
Also driving adoption is the fact that it's getting much easier to turn the sensor output into useful applications. The leading MEMS device makers like STMicroelectronics and InvenSense are supplying more software and libraries to make it easier for the phone and tablet makers to add basic motion functions to their systems. Dedicated motion sensor software suppliers like Movea and Hillcrest Labs are supplying device-agnostic software to allow wider applications, particularly for air mice and TV remotes to do control by gestures. And the latest version of Android operating system software supports some motion processing APIs, with more sophisticated versions expected to come.