What kinds of controls can an operator use to affect a machine?

In human-factors engineering, an operator interacts with a machine by translating decisions into physical actions upon specific controls. These controls serve as the interface through which the human exerts influence on the machine’s output.12

Common types of controls include:

• Manual physical controls: Traditional mechanical interfaces such as push buttons, levers, cranks, pedals, switches, and handles.1
• Computer input devices: Modern interfaces designed for digital systems, including keyboards, keypads, and pointing devices like a mouse, trackball, or joystick.3
• Advanced and specialized interfaces: Technologies that leverage human perceptual and cognitive abilities, such as touch-based gesture recognition, handwriting recognition, and speech input.3
• Brain-computer interfaces (BCIs): Emerging technologies that allow users to manipulate systems through brain activity rather than motor movement, which is particularly significant in bioengineering applications for individuals with physical disabilities.3

The design of these controls is critical, as they must accommodate human physical and cognitive limits while providing appropriate feedback to guide the operator's actions.13