Monitoring,Measurement and Control

Monitoring,Measurement and Control

1. Sensors

   • can open doors (Pressure sensors)
     • can be used in offices to open doors when people stand in front of them it automatically opens
   • sensors measure light, heat, humidity and water etc
     • send signals to an interface box
       • results that are in digital (numbers) can be changed into binary (010101)

2. Data Logging

   • Is the collection of data of a period of time
     • uses sensors
     • linked to a computer
     • the sensors in a greenhouse are:
       • Humidity
       • Tempurature
         • if it is below the desired temprature the heater turns up
           • if it higher than the desired temprature then the heater will cool down
       • Moisture
     • advantages
       • Takes readings with high accuracy
         • Readings are made 24/7 with no breaks
         • Can be situated in places humans cant go (Underwater, north pole)
           • Mistakes are rarely made
             • Automatic and can be left without human tampering
           • The system doesn't forget to take the reading
     • disadvantages
       • The equipment is VERY expensive
       • Malfunctions can cause errors in the readings
       • if the computer shuts down or breaks data will be not read correctly or not at all

3. Converters

   • ADC
     • Analogue to Digital Converter
       • DAC
         • Digital to Analogue Converter
           • Translates binary numbers into sound so humans can understand it
             • 0's and 1's
               • 0=off 1=on
       • Translates sound into binary numbers a computer can understand

4. Control

   • thermostat heating control
     • changes the heating if desired

5. Everyday life

   • Offices
     • Fob's can be used to let people with certain access rights into certain places like locked rooms with safes in
     • to use a fob all people do is scan it against a block on the wall and it lets them in
   • People
     • cameras such as CCTV cameras can monitor what people are doing and gives them evidence for the crime or break in

6. Monitoring

   • in Prisons an alarm is sounded if someone has escaped
   • Hospitals
     • Monitors check patients heart beat
       • check their oxygen levels
         • and if they are breathing
           • so if there is anything wrong the doctors can immediatly come to help
             • by sounding a loud alarm
           • also is there brain in danger?