1. Signal Sources B. Furman 31JAN2013

2. Mechatronics Concept Map System to Control Sensor Signal Conditioning Controller (Hardware & Software) Power Interface Actuator User Interface Power Source BJ Furman 15JAN11 ME 106 ME 154 ME 157 ME 195 ME 120 ME 297A ME 106 ME 120 ME 106 ME 190 ME 187 ME 110 ME 136 ME 154 ME 157 ME 182 ME 189 ME 195 ME 106 ME 120 ME 106 INTEGRATION

3. Signal Sources - 1 Signal source concept  Sensors as an information source Their output voltage or current level encodes information about the quantity to be measured  Remember the dishwasher light sensor example?  Output voltage proportional to intensity of light Most often information is encoded as a voltage level  Ex. The voltage output from a Wheatstone bridge  The information: weight on the scale encoded as a voltage Current level also used  4 – 20 mA commonly used in industrial controls  Signals to power interface

4. Signal Sources - 2 Sensor data sheets  ADXL203 Precision ±1.7 g dual-axis accelerometer  Can use also to sense tilt  iPhone display 1000 mV/g sensitivity  17mg/deg from horizontal  17 mV/deg tilt http://www.analog.com/static/imported-files/data_sheets/ADXL103_203.pdf  mg mgsin(  ) force component xx Slope=sensitivity Sine function Horizontal Tilted

5. Signal Sources - 3 Ideal signal source  Ideal voltage source  No output impedance V out Input quantity Practical signal source  Relatively low-level output  Finite output impedance  Prone to noise  Zero offset  Non-linear 1V/g noise RoRo V out Input quantity