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MEMS in space
The satellite industry could experience its biggest
revolution since it joined the ranks of commerce, thanks to some of the
smallest machines in existence. Researchers are performing experiments
designed to convince the aerospace industry that microelectromechanical
systems (MEMS) could open the door to low-cost, high-reliability,
mass-produced satellites.
MEMS combine conventional semiconductor electronics with beams, gears,
levers, switches, accelerometers, diaphragms, microfluidic thrusters, and
heat controllers, all of them microscopic in size."We can do a whole
new array of things with MEMS that cannot be done any other way,"
said Henry Helvajian, a senior scientist with Aerospace Corp., a nonprofit
aerospace research and development organization in El Segundo, Calif.
Microelectromechanical Systems, or MEMS, are integrated
micro devices or systems combining electrical and mechanical components.
They are fabricated using integrated circuit (IC) batch processing
techniques and can range in size from micrometers to millimeters. These
systems can sense, control and actuate on the micro scale, and function
individually or in arrays to generate effects on the macro scale.
MEMS is an enabling technology and current applications
include accelerometers, pressure, chemical and flow sensors, micro-optics,
optical scanners, and fluid pumps. Generally a satellite consists of
battery, internal state sensors, communication systems and control units.
All these can be made of MEMS so that size and cost can be considerably
reduced. Also small satellites can be constructed by stacking wafers
covered with MEMS and electronics components. These satellites are called
'I' Kg class satellites or Picosats. These satellites having high
resistance to radiation and vibration compared to conventional devices can
be mass-produced there by reducing the cost. These can be used for various
space applications.
Also small satellites can be constructed by stacking wafers covered with
MEMS and electronics components. These satellites are called 'I' Kg
TECHNOLOGY
Although MEMS devices are extremely small MEMS
technology is not about size. Instead, MEMS is a manufacturing technology;
a new way of making complex electromechanical systems using batch
fabrication techniques similar to the way integrated circuits are made and
making these electromechanical elements along with electronics.
Material used
The material used for manufacturing MEMS is Silicon. Silicon possesses
excellent materials properties making it an attractive choice for many
high-performance mechanical applications (e.g. the strength-to-weight
ratio for silicon is higher than many other engineering materials allowing
very high bandwidth mechanical devices to be realized).
Components of MEMS
Micro-Electro-Mechanical Systems (MEMS) is the integration of mechanical
elements, sensors, actuators, and electronics on a common silicon
substrate through the utilization of micro fabrication technology. MEMS is
truly an enabling technology allowing the development of smart products by
augmenting the computational ability of microelectronics with the
perception and control capabilities of micro sensors and micro actuators
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