Computers are sometimes used alongside sensors to measure quantities such as pressure, temperature, radiation etc. This is known as 'data logging'.
Sensors and Data Logging
Sensors are used to automatically detect and measure physical quantities.
If the sensor is connected to a computer, the computer can read the data coming from the sensor and log it at pre-set time intervals (hourly for example). This is sometimes called 'data logging'.
This allows us to see changes in the quantities (temperature increasing or decreasing for example)
Why use a computer to measure sensor data instead of a person?
Computers are much better at reading and measuring quantity data taken from sensors for the following reasons:
Examples of Computer Measurement Applications
Data logging can be setup to automatically monitor and record data generated by scientific experiments.
Water Temperature Example: Imagine you are conducting an experiment that records the temperature of water as it transforms from solid ice into hot steam. You would need to use the following:
Thermostat - to measure the temperature of the water ADC - to convert the analogue temperature data into digital Computer - to receive and log the digital temperature data Software - to analyse the received data
Electronic Timing
Computerised data logging can be used to accurately measure time.
Olympic 100 Metres Race Example: In sprinting, generating accurate race times is important as, sometimes, first and second place can be separated by 1000's of a second. To accurately measure athlete's race times you would need:
Sound Sensor - to record when the race is started Infrared Sensor - to record when the athlete crosses the finish line ADC - to convert the analogue data from the sensors into digital Computer and Software - to receive and log the digital data and calculate race time.
Environmental Monitoring
Environmental monitoring is where data is collected to be used for purposes such as:
Weather forecasting Water quality in rivers and streams Levels of air pollution
Weather Forecasting Example: Weather stations contain lots of sensors which are used to gather a variety of different data. For example:
Thermometer - to measure temperatures Humidity Sensor - to measure the amount of water in the air Barometer - to measure air pressure Anemometer - to measure wind speed Rain Gauge- to measure the amount of rain fall over a certain period.
These sensors would feed data into a computer which is then analysed by meteorologists (weather forecasters). The data allows the weather forecasters to make predictions about future weather.