Creating Effective Decision Aids for Complex Tasks
Caroline Clarke Hayes and Farnaz Akhavi
Journal of Usability Studies, Volume 3, Issue 4, August 2008, pp. 152-172
Article Contents
The Design Tasks
We studied student designers in the context of two different electro-mechanical design domains: design of a robot arm for a quadriplegic man and design of a manned lunar excursion vehicle. The robot arm for the quadriplegic man had to be capable of manipulating a variety of lightweight objects found in his home and office environment such as paper, small books, compact discs, and soft drink cans. It had to have a control interface that a quadriplegic person could manipulate and be powered by the on-board battery system of his electrically powered wheelchair. Additionally, it had to be simple for an assistant to mount and unmount from the arm of the wheelchair. The electronics and motors had to be reasonably weatherproof, light weight, and inexpensive. To meet the cost goals the students made extensive use of scrap aluminum and junk yard parts such as automobile seat motors. Finally, the students had to build and test their best design, shown in Figure 2.
Figure 2. A wheelchair mounted robot arm created by a student design team.
In the second domain, teams of student designers developed designs for manned lunar excursion vehicles, some of which are shown in Figure 3. All groups were given the same design goals by the NASA Johnson Space Center. They were to design a manned lunar excursion vehicle that would provide occupants with protection, life support, mobility, towing capability, communication, and sufficient power for an average excursion. The excursion vehicle must also fit inside the launch vehicle and deploy successfully at the landing site. Students did not have the tight budgetary restrictions as the students building the robot arm, nor did they have to build the excursion vehicle.
Figure 3. Four design alternatives for a lunar excursion vehicle developed by students.