16 February 2017

Where man meets machine


Industrial terminology can be tricky if you’re not used to it. When it comes to electrical components, the abbreviations HMI and PLC are often seen. But what on earth is HMI? HMI stands for Human Machine Interface, which sounds like something out of a sci-fi movie but put simply, it’s the means by which a user interacts with and controls a machine.

The HMI is the part of the machine that handles the human-machine interaction and could be anything such as switches, keypads and touchscreens for example. In more complex systems, the HMI is normally computerized, making it a Human – Computer Interface. The term also applies to the software that is used to control the physical parts. When these interfaces are designed, they are done so with consideration for the ergonomics of use and how a person can use something comfortably and easily. This is also referred to as human factors engineering or usability engineering. For Electrical Control Components manufacturers, visit http://www.osmelectrical.com/.

Where man meets machine

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Including human factors into interface design uses tools which are developed from a knowledge of computer science, computer graphics, operating systems and programming languages. As most human-machine interfaces on computers are now using graphics, we refer to these as graphical user interfaces.

Truly effective interfaces have the following qualities:

  • Clarity – the interface must avoid being ambiguous by making everything clear through its use of language, metaphors for visuals, flow and hierarchy.
  • Familiarity – certain elements must be instantly recognisable even for first time usage.
  • Concise – an interface can become stuffed with excess labeling in an attempt to over-clarify everything with a danger of having too many items on screen at one time. If it’s hard to find what you’re looking for, it becomes annoying and time-consuming. A great interface needs to be clear and concise together.
  • Consistent – an interface should be consistent across an application so users can recognise usage patterns.
  • Responsiveness – an effective interface should not feel slow or sluggish and so a good design would feed back information about what’s happening and whether the input is being processed successfully.
  • Kind – a helpful interface will not make life difficult for a user if they make an error but should provide advice on how to remedy the mistake.
  • Aesthetics – something doesn’t need to be pretty to be effective but why not make an experience more enjoyable. If it looks the business then users will be happier.
  • Efficiency – shortcuts and an easy to use slick design will both save time and time is money folks.

POLA is an abbreviation that will mean a lot to those designing such interfaces. It stands for the principle of least astonishment and is a general principle in the design of many different types of interfaces. The idea is that humans can only pay full attention to one thing at a time and therefore something unusual or novel should be minimized as much as possible.