A model for types and levels of human interaction with automation

Technical developments in computer hardware and software now make it possib le to introduce automation into virtually all aspects of human-machine syst ems. Given these technical capabilities, which system functions should be a utomated and to what extent? We outline a model for types and levels of aut omation that provides a framework and an objective basis for making such ch oices. Appropriate selection is important because automation does not merel y supplant but changes human activity and can impose new coordination deman ds on the human operator. We propose that automation can be applied to four broad classes of functions: 1) information acquisition; 2) information ana lysis; 3) decision and action selection; and 4) action implementation. With in each of these types, automation can be applied across a continuum of lev els from low to high, i.e,, from fully manual to fully automatic. A particu lar system can involve automation of all four types at different levels. Th e human performance consequences of particular types and levels of automati on constitute primary evaluative criteria for automation design using our m odel. Secondary evaluative criteria include automation reliability and the costs of decision/action consequences, among others. Examples of recommende d types and levels of automation are provided to illustrate the application of the model to automation design.