Many ship systems are controlled by computers. These computers interact with the operator by means of TFT screens, keyboards, mouses, trackballs and other dedicated input devices.
In the past decades the introduction of computers enabled a reduction in crew size. At the same time – specifically on special purpose ships – the amount of information the operator is confronted with, can sometimes exceed his cognitive capabilities.
An effective way to keep the operators cognitive workload within acceptable limits, is by using ergonomically designed User Interfaces.
Some basic characteristics are:
- The amount of distinct User Interfaces is kept to a minimum. In this case ‘less is often more’.
- The User Interface design allows the operator to have a maximum of situational awareness at a minimum of cognitive workload.
- Alarm rates are low (typical max. 1 per 10 min).
- The ratio between font size, screen size and viewing distance is designed according to common Human-Computer-Interaction guidelines (like in ISO 11034).
- If User Interfaces are used in bright daylight, but also in dusk and night situations, separate day/dusk/night colour schemes are provided. An alternative way is to use special marine-spec monitors with 0-100% backlight dimming – or a combination of both options.
- Well-designed User Interfaces can often be recognized by a simple, sober and stylistic appearance.
- Information redundancy (same information is displayed on two or more instruments, often in various formats) is avoided.
- Essential information is displayed permanently to the operator, and always at the same location.
- The optimal amount of keyboards is related to the amount of hands an operator is born with.
Be noted that on a ships bridge direct vision of the environment outside is in many situations the best possible and most reliable User Interface of all. This means that the position and size of TFT screens should never obstruct the outside view.
This is specifically important when modern large screens (> 32”) are applied.
Some suppliers of maritime instrumentation offer ‘integrated bridge’ solutions. These concepts are usually well-designed and of a high standard. However, integrated bridge solutions are a costly option. When using an ergonomic design approach, a similar high standard can also be obtained by using standard equipment. This is usually a much more cost-effective option.
For more information on User Interfaces, contact ErgoS HFE.