Tuesday, April 24, 2007

MEMS Technology: It's Everywhere and Growing (or shrinking) Fast!

as posted: http://www.memsnet.org/mems/what-is.html


Micro-Electro-Mechanical Systems (MEMS) is the integration of mechanical elements, sensors, actuators, and electronics on a common silicon substrate through microfabrication technology. While the electronics are fabricated using integrated circuit (IC) process sequences (e.g., CMOS, Bipolar, or BICMOS processes), the micromechanical components are fabricated using compatible "micromachining" processes that selectively etch away parts of the silicon wafer or add new structural layers to form the mechanical and electromechanical devices.

MEMS promises to revolutionize nearly every product category by bringing together silicon-based microelectronics with micromachining technology, making possible the realization of complete systems-on-a-chip. MEMS is an enabling technology allowing the development of smart products, augmenting the computational ability of microelectronics with the perception and control capabilities of microsensors and microactuators and expanding the space of possible designs and applications.

Microelectronic integrated circuits can be thought of as the "brains" of a system and MEMS augments this decision-making capability with "eyes" and "arms", to allow microsystems to sense and control the environment. Sensors gather information from the environment through measuring mechanical, thermal, biological, chemical, optical, and magnetic phenomena. The electronics then process the information derived from the sensors and through some decision making capability direct the actuators to respond by moving, positioning, regulating, pumping, and filtering, thereby controlling the environment for some desired outcome or purpose. Because MEMS devices are manufactured using batch fabrication techniques similar to those used for integrated circuits, unprecedented levels of functionality, reliability, and sophistication can be placed on a small silicon chip at a relatively low cost.

Monday, April 02, 2007

3-Axis Acceleration Measurement Possibilities

I have had several discussions concerning measuring acceleration and/or vibration in 3 axes. There are several ways to accomplish this:

The B, BD, and BDK single axis accelerometers can be mounted in a tri-axial formation using either the SW3 Mounting Cube or the BS24 Mounting Cube. The BS24 is smaller than the SW3 and allows the user to move the sensor around on the block and switch out sensors to change the range or replace with a new sensor. The SW3 format is a permanent configuration, if one sensor is damaged the entire unit must be replaced. Please note, the BS24 is limited as far as its compatibility, accepting only the B Series or NB3 Sensor with special threading.

Another option is the SB3Gi. This is an out of box solution using a die-case aluminum IP65 housing with 3 integrated accelerometer sensors with 3 signal conditioners. This factory calibrated package provides 3 analog current 4-20mA 2-wire current loop outputs, powered by an 8-30VDC non-regulated supply.