Robots work using a combination of electronics, computer programming and mechanics called mechatronics. Electricity is key to the functioning of these robots.
Usually, a robot is made up of 5 distinct components that mimic the human body, which are:
- a body structure
- a ‘muscle’ system – motors and a means of moving the robot
- a number of electronic sensors
- a source of energy – a battery
- a computer ‘brain’ – a means of controlling the electrical systems.
Robots are designed for many different purposes, usually for the repetitive jobs or those that are extremely dangerous or difficult for humans to do. In this way, humans can extend their senses and actions using robots.
Robots such as MARVIN (which stands for Mobile Autonomous Robotic Vehicle for Indoor Navigation) have ultrasound and infrared sensors that allow them to detect distance, as well as touch and sound sensors. The electrical properties of the sensors change when there is a change in the physical conditions that they can detect. Find out more in the article Sensing robots.
Search and rescue robots being developed by Dale Carnegie and his team at Victoria University have sensors capable of detecting heat using thermal imaging, gases, such as carbon dioxide and also movement.
How do robots respond?
All robots operate by making a series of electrical decisions based on the information the sensors receive.
The robot doesn’t have a brain to make these decisions like humans do but instead relies on its microprocessor (computer) to analyse the signals from the sensors and send response signals to electrical circuits or electronic components that control the flow of electric charges to various parts of the robot.
These electrical responses (decisions) change what the robot is doing. A complex robot may have hundreds of decisions to make.
The robot's computer is programmed to control everything attached to its circuitry. To enable the robot to move or respond, the computer switches on the different motors or components as required. To change the way the robot behaves, you simply write a new program into its computer.
Can robots have emotions?
Robots that are designed for specific tasks have to be taught how to do these tasks – they have to have computer programs that will allow them to react to many different types of situation and actually learn from them, such as avoiding an object after having collided with it.
Dale Carnegie and his team have equipped MARVIN, a security robot, with a set of emotions to help MARVIN survive in situations that otherwise it might find itself stuck in. MARVIN uses its sensors to determine where it is and the obstacles that may get in its way. It is programmed to feel ‘frustration’ when it is stuck somewhere. When this happens, its movements become more aggressive. Is this like human intelligence, which is the ability to react to and respond to a situation in the most appropriate way, even when you've never encountered it before?
Most robots have a lot of these types of built-in electronic circuits that make decisions and responses. When they have a series of more complex electronic circuits, they can perform multiple functions such as moving, sensing and receiving, and sending information.
Research by the Mechatronics Group at Victoria University is leading to the development of robots that will be fully autonomous with no need for human intervention.
Nature of science
Scientists work collaboratively with technologists to research, design and build technological appliances based on basic science principles. The principles of electrical circuits, computer programming and mechanics are brought together in novel ways to design robots with varying functions and also to create robots that can be autonomous.
Use these activities introduce students to the science of electrical circuits:
- Testing for conductivity involves the construction of simple electrical circuits to test a variety of materials for their conductive abilities.
- Challenging switches involves the construction of electrical circuits to explore the role of switches.
- Sensing moisture involves the construction of a simple, effective moisture sensor.