1. Power Laws and Log-log Plots
Slope = n
Intercept = log k
Incroprera, Fundamentals of Heat Transfer, 6th edition (2006).
General Linearization
transformation
Use linear curve fit to get a and b, which can be used to extrapolate physical parameters.

2. RTD – Resistance Temperature Detector
The resistivity of a metal changes linearly with temperature.
Lab1: Voltage divider circuit

3. Thermistor Steinhart Eq.
Works the same as an RTD, except the sensing material is made of a ceramic or a semiconductor.
Steinhart Eq.
Lab 1
Non-linear response

4. Voltage Divider Circuit

5. Often wired up in a Wheatsone bridge configurartion
Strain Gauge (or Gage)
Measures strain based on change in resistance
Ge ≈ 2 “gage factor”
Fig. 4.4
Often wired up in a Wheatsone bridge configurartion

6. Wheatstone Bridge

7. Micro-Electro-Mechanical Systems (MEMS)
Modern Accelerometers
Acceleration causes mass to push on spring and displace the “interdigitated” electrodes,
changes electric capacitance.
Micro-Electro-Mechanical Systems (MEMS)
3-axis gyro from an iPhone 4

8. In E1a, you will use this 3-axis accelerometer
Lab1 Accelerometer Calibration
In E1a, you will use this 3-axis accelerometer