Degree Type


Date of Award


Degree Name

Doctor of Philosophy


Industrial and Manufacturing Systems Engineering

First Advisor

Patrick E. Patterson


Advances in modern farming technology provide automation features that lighten the workload for operators of farming equipment. One of the many technologies incorporated in modern agricultural equipment is automated steering systems like the John Deere's Green-Star Auto-Trac System(TM), which is a hands-free steering system for straight-line driving applications. When using a machine that is equipped with one of these systems, the work load of the operator is lightened and enables the operator to perform other tasks while doing field work. Many people believe a tractor cab could become a mobile office in the near future with the operator using a personal computer to take care of various office tasks while working in the field. The goal of this research was to investigate the feasibility of using a computer, running standard office applications, in a moving off-road vehicle with semi autonomous controls. In separate studies commercially available input devices for pointing and alphanumeric input were evaluated to determine those best suited for performing office computer application tasks in a mobile off-road environment. The pointing and alphanumeric input devices that seemed best suited for the tested environment were combined into sensible user interfaces, and they were evaluated for usability and performance a user can expect with them. The results showed that the mouse, touch screen and the standard QWERTY keyboard are the input devices that provide the best usability. These devices showed good results in the objective performance measurements as well as in the subjective user evaluations. They are therefore well suited to be used in the tested environment. With these devices the usability and performance a user can achieve in a moving off road environment are reduced compared to those in an office environment but still satisfying to the user, which encourages the implementation of such a system in the future.



Digital Repository @ Iowa State University,

Copyright Owner

Thorsten Baldus



Proquest ID


File Format


File Size

197 pages