An Evaluation of Menu Systems for Space Station Interfaces

Abstract

The purpose of this study was to evaluate menu systems as a means of meeting proposed basic requirements for Space Station interfaces. Three command modes were evaluated: 1) the direct mode, which displayed no menus to the subjects; all commands were typed on a QWERTY keyboard, 2) the menu mode, in which menus were displayed; all commands were selected from the menus via cursor control, and 3) the hybrid mode, which presented the same menus as were displayed in the menu mode, but subjects were free to select commands from the menu via cursor control or type them in directly. Experienced and inexperienced users performed tasks using each of the three command modes. The main performance measures indicated that the direct mode was superior to the hybrid and menu modes, yet subjective data showed a clear preference for the hybrid mode. These results were the same for the experienced as well as the inexperienced group of subjects. Based on the overwhelming preference by both groups of subjects for the hybrid mode, it is recommended that a hybrid menu system similar to the one employed in this study be a strong candidate for implementation in Space Station interfaces. However, due to the processing, display, and search resources demanded by menus, it is also recommended that users be given a simple means to activate and deactivate the menu as desired. This study shows that the menu selection dialogue can be a useful and even preferred interactive environment for all levels of users, but only if it is well designed and flexible enough to meet their different and varying needs.