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MEMS Class 6 Modeling of MEMS Devices Mohammad Kilani. 20 mm. 10 mm. The Scaling of MEMS Devices. 2 mm. 1 mm. Isometric Scaling. How does electrostatic force change? How does electrostatic force change relative to other forces? How does response time change?. 20 mm. 10 mm.
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MEMS Class 6 Modeling of MEMS Devices Mohammad Kilani
20 mm 10 mm The Scaling of MEMS Devices 2 mm 1 mm Isometric Scaling How does electrostatic force change? How does electrostatic force change relative to other forces? How does response time change?
20 mm 10 mm The Scaling of MEMS Devices 2 mm 1 mm Isometric Scaling
Water Bug Weight = V S3 Surface Tension = kA S2 Man : 2m Bug: 2 mm S = 1/1000 Surface Tension / Weight S2/S3 = S-1 = 1000 Water bug uses surface tension to walk on water
The Scaling of Forces 20 µm 2000 µm 10 μm Isometric Scaling 1000 μm S = 1/100 Weight = gm = gV S3 Electrostatic Force = kA S2 Electrostatic Force / Weight S2/ S3 = S-1 = 100
The Scaling of Work or Mechanical Energy Gravitational force S3 Wok of gravity S4 If S = 1/100 the gravitational energy required to move an object from the bottom to the top of the machine under consideration decreases by (1/100)4 = 1/100,000,000. Drop an ant from ten times his height, and he walks away. Please do not try this with a horse!
The Scaling of Acceleration A predominance of the forces we use in the microdomain scale as S2. For these forces, the acceleration scales as S−1. If S = 1/100, a increases by a factor of 100. Small systems tend to accelerate very rapidly.
The Scaling of Velocity For the case where the force scales as S2, velocityscales as S-0.5. If S = 1/100, the velocity increases by a factor of 10. Small things tend to be fast.
The Scaling of Response Time The time needed to travel a certain distance, x is given from the relation Assume constant a For the case where the force scales as S2, transit time t scales as S1. If S = 1/100, the transit time decreases by a factor of 100. Small things tend to be fast.
The Scaling of Mechanical Power The time needed to travel a certain distance, x is given from the relation For the case where the force scales as S2, powerscales as S2. If S = 1/100, the power decreases by a factor of 10000. Small things have very small mechanical power.
The Scaling of Magnetic Forces 1. Constant current density Ib Ia L
The Scaling of Magnetic Forces 2. Constant heat flow through the surface of the wire Ib Ia L
The Scaling of Magnetic Forces 3. Constant temperature rise of the wire Ib Ia L
The Scaling of Magnetic Forces 4. Wire and permanent magnet Ia L 1. Constant current density: F S3 2. Constant heat flow: F S2.5 3. Constant temperature rise: F S2