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Week 1

Applied Measurement and control

  • Applied: Hands-on
  • Measurement: Principels of measurement, with focus on measuring environmental variables
  • Control: "control" of actuator and the data flow and routing. Not control in the formal sense of Control Theory. Althoudght we would loady refer to concepts from control theory but without formal or regorus academic perspective and more a "applied view".

Outline​

  • Measurement itself is inharently affected by errors,

    • measurement errors
    • tools errors
    • external factors

  • Error Analysis introduction

  • Environmental Measurement techniques

    • ground-based sensors (direct contact)
    • Wireless sensors (in-direct contact)
    • Air-borne
    • Space-born

  • Calibration (important step for environmental data)]

  • Why we want to do it

  • What we need, Environmental Monitoring in the Field:

    • Microcontroller
    • Sensors
    • Realtime clock
    • Local data storage
    • Date exchange facility (e.g. USB cable)
    • Maybe additional wireless date transfer
    • Power (mains or battery)
    • Maybe additional solar panel to recharge battery
    • Waterproof enclosure

  • What we need to consider:

  • Examples:

Error Analysis​

Error analysis is the study and evaluation of uncertainty in measurement.

no measurement, however carefully made, can be completely free of uncertainties. Chapter 1

We build science around the capacity of perform measurements

"... the ability to evaluate these uncertainties and keep them to a minimum is crucially important."

[BIG SLIDE]: the word error does not carry the usual connotations of the terms mistake or blunder.

In our context error = uncertainty

Play the example es measuring distance

  • get a stick and estimate the error

  • ruler and tape

  • caliper

  • interferometer (limited by the wavelength of light)

  • measuring in different spots

  • humidity and temperature affecting the material

problem of definition (the height of the door is not a well-defined quantity)

no physical quantity (a length, time, or temperature, for example) can be measured with complete certainty.

ISO/IEC Guide 99:2007, the International Vocabulary of Metrology (VIM)

ISO/IEC Guide 99 defines measuring transducer as a device, used in measurement, that provides an output quantity having a specified relation to the input quantity (entry 3.7). It defines sensor as an element of a measuring system that is directly affected by a phenomenon, body, or substance carrying a quantity to be measured (entry 3.8).