Sensor Technology for Machines 1

What is a primary purpose of measurement systems in machines?

• Decoration

• Monitoring processes and ensuring quality

• Noise reduction

• Marketing

Which is a direct method of measurement?

• Measuring length with a ruler

• Calculating speed from distance and time

• Weighing via spring balance and density

• Estimating temperature by touch

Indirect measurement means:

• Guessing value

• Comparing with standard

• Calculating desired value using related measurements

• Only using qualitative description

Which is NOT a part of a typical measurement system?

• Sensor

• Signal conditioner

• Transmitter

• Marketing survey

Which is a major reason for calibration in measurement systems?

• Decoration

• Ensuring traceability and accuracy

• Increasing cost

• To avoid using standards

A sensor is best defined as:

• Any device with a battery

• Device converting a physical quantity to a measurable signal

• Only electronics with displays

• A data storage unit

Active sensors:

• Generate their own signal without external power

• Require external power to operate

• Never require calibration

• Only used for light sensing

Which is an example of a passive sensor?

• Photodiode

• Piezoelectric sensor

• Strain gauge

• RTD

Digital sensors output:

• Only continuous voltage

• Discrete (often on/off or step) signals

• Sound

• Smoke

"Proprioceptive" sensors in robotics sense:

• External environment only

• Internal parameters (e.g. speed, angle)

• Only temperature

• Human motions