Artificial sensors explained

Extending human senses involves finding ways to monitor our environment so that we can ‘see’, ‘feel’ or ‘hear’ things beyond what our senses allow us to do and enable us to respond to changes.

Using artificial sensors, we can sense things over long distances or in places that are dangerous for humans (for example, monitoring the poisonous gas given off by an active volcano or going down sewage pipes). We can also use sensors to track and record movement in various situations, from animal migrations to the location of delivery trucks or boats lost at sea.

We can monitor and record changes in our environment over days, weeks or years, and the information can be stored. Trends can then be observed, which is a key aspect of science – observing patterns in the changing world around us.

Mobile radios, mobile phones, cameras, satellites and computers are examples of technologies that have allowed humans to extend their senses and memories by detecting, storing and communicating data. It is this use of technology that has extended our scientific understanding of the world.

Saving lives

We could not predict an earthquake or a tsunami using the usual range of human senses, but by using artificial sensors, we can save lives by predicting when a disaster such as a tsunami might happen because people can evacuate the disaster area ahead of the event. Electronic sensors can also do tasks automatically, such as triggering an alarm, indicating when a volcanic lahar flow is about to happen.

We can use robots to sense where people are buried in dangerous places, like collapsed buildings. Human searchers cannot fit into small crevices or rubble, but special robots can. They are equipped with electronic sensors to detect and communicate movement, heat, human sounds and carbon dioxide levels, which may indicate people breathing.

Sensing relies on electrical systems

All sensors (including those in our bodies) rely on electrical systems to capture, analyse and relay information. Electrical systems are made up of wires and components that are able to switch or change an electrical current. It is the ability to detect change in the electrical current that allows sensors to work.

The electrical system in our bodies is made up of nerves connected to our spinal chord or our brain. Just like our bodies, artificial sensors are connected to electrical systems to transfer input signals so they can trigger automatic responses or more intelligent responses.

MARVIN the robot, developed by researchers at Victoria University in Wellington, has multiple sensors to detect movement, touch, distances of objects (‘sight’), distance it travels and human sounds. As soon as the sensors detect a change in the environment, they send electrical signals to other components, which act to trigger MARVIN’s responses, and these changes in the flow of electricity may switch other components on or off.