In other cases, there are Project-specific requirement which tend to be more precisely defined, as well as being focused a specific project. It is often tempting to borrow the requirements from a previous project. The following table shows examples of the types of requirements that are typically addressed for different aspects of design. Summary Design is all about making things that work. Human machine systems don't work effectively if they are hard to learn and hard to use.
Requirements are a way of steering designers away from bad solutions.
The human requirements in a system are of course just part of the many requirements designers may have to face. For instance, low power utilization may be a technical requirement that has little direct relationship to the human requirements in a system. Difficulties sometimes arise when there is a conflict or tradeoff between human and other system requirements. For instance, a human requirement might lead to a more expensive product, or to a system with less capability. We shall consider the important issue of design tradeoffs in Lecture 12.