Proliferation of MEMS Sensors Equals Greater Awareness to “Things”
By Tony Massimini
The MEMS market is poised for significant growth thanks to major expansion of applications in smart phone and automotive. These two applications driving the increase use of MEMS sensors and actuators will further reduce cost and power while increasing performance, thus fostering new markets including health and fitness as well as home and building automation. Finally, the continuing growth of MEMS will provide new injection of growth in the slowing semiconductor market.
In 2013, Semico expects a total MEMS market of $16.8 B but by 2017 it will have expanded to $28.5 B, a 70 percent increase in a mere four years time. In 2011, 39 percent and 30 percent of all MEMS were being made for automotive and smart phone applications, respectively. Today, Semico expects 40 percent to be destined for smart phones and a mere 25 percent for automotive. Today’s smart phone will not only have the standard accelerometer, magnetometer, and gyroscope; it will also come with pressure sensor to provide altitude data—detailing the floor in a high rise of the user—as well as MEMS in one or more microphones, in the autofocus of the cameras and in SAW filters and resonant cavities in the radio of the phone.
All of these sensors are creating a need for a separate sensor hub processor, which has a 32-bit processing core for handling advanced algorithms. The most dominant solution today are standard microcontrollers. There are about 18 MCU vendors with ARM cores such as Freescale, STand others. The Atmel AVR MCU family has a significant presence. Other sensor hub solutions are emerging such as the integrated sensor hub in the Qualcomm Snapdragon 600/800 application processors, based on ARM core architecture and Intel’s upcoming Atom Merrifield CPU.
Other solutions are ASSPs such as ASIC, FPGA and specialized devices. Separate from the phone’s application processor, this sensor hub runs complex sensor fusion algorithms that provide data to the apps processor’s OS for distribution to the APIs. What might this fusion processor provide? Take the magnetometer in most cell phones as an example. In a building, reflections can produce false readings. By knowing where the phone is within a building the sensor fusion system can provide corrections for these anomalies.
Sensor fusion algorithms will begin to provide greater context awareness for the sensor reading thus enabling applications software to better anticipate a phone user’s needs and requirements. Detecting that a phone is no longer moving, the phone can be powered down to cut the large power consumption of the gyroscope, applications processor, as well as other elements of the smart phone that are not needed at that moment.
Whatever is developed for the phone will be applied to automotive and other consumer devices. In the car, sensor fusion will provide the kinds of context awareness that factors speed and radar responses to determine when to automatically apply brakes to avoid a collision. Context awareness in the phone can also help reduce power consumption. In consumer devices such as digital still and movie cameras, images can be tagged for exact geographic location and orientation in Cartesian space as well as time of day.
All the sensor technology developed for the automotive and smart phone markets can be applied in home and building automation as well as health and fitness applications. Semico believes that the sensor proliferation in homes could easily outstrip their application in industrial applications. Sensors can be applied in easily 70 different “things” within the home: lights, security and safety, heading and air conditions as well as appliances.
In health and fitness, sensors are being applied to enable an aging population to remain at home monitored by a range of vital sign monitors. These same types of monitors can provide performance data to enable the health conscious population to record their physical activity and provide feedback to optimize workout regimens. These sensors will also create additional demand for more capable smart phones, which will provide the sensor fusion function before relaying the data onto health care professionals or fitness coaches. In animal husbandry, these sensors will be used to monitor the health of livestock: to determine optimum breeding cycles, to detect unhealthy animals and determine which peers to cull and which to isolate to reduce the spread of disease.
As the number of sensors increase and enable an Internet of Things, there will be an increased demand for lower power interfaces, such as the low-energy Bluetooth, to create the sensor networks that will link these sensors to the Cloud. At the 2013 Sensors Expo in Chicago, the discussion included mesh networks that could move data node to node eventually reaching a central controller to add context to the raw data before moving it onto the Internet and eventually to the Cloud.
The MEMS sensor is at the center of an emerging new market of intelligent “things” that will provide users as well as inanimate objects such as automobiles a greater awareness of their surroundings. As the technology evolves, these sensors will become less expensive while providing greater sensitivity, thus opening up greater numbers of applications.