Project Description

VuMan 1 allows a user to maneuver through the blueprints of a house using three buttons for input. Output is provided on a commercially available head-mounted display, the Private Eye, which gives the illusion of viewing a personal computer screen from about five feet. Composed of only five chips, VuMan 2 allows the user to move a cursor across the display and select items from either a map, image database, or textual database. New applications can be loaded into VuMan 2 by inserting a different Flash EPROM memory card into the PCMCIA slot. VuMan 2 represented a factor of four reduction in complexity, weight, volume, and power consumption over VuMan 1 but with an increase of over a factor of two in capability and a reduction of 40% in design/fabrication effort. VuMan 2's main applications are a CMU Campus Tour navigation and Maintenance Assistant. VuMan 2R is a ruggedized version of VuMan 2. It incorporates a new housing design to withstand shock, temperature, water, and dirt. Its printed circuit board has some enhanced capabilities for input and power control. VuMan 2R uses an input interface combined of a rotary dial and a single push-button. The speed and easy for a user to scroll through many options that may appear on a screen of the Private Eye display are the reasons for the use of a rotary dial. A link is provided between VuMan 2R and a Logistical Maintenance Computer (LMC) so that results from vehicle inspection check lists can be uploaded for scheduling and planning.

VuMan 3 has included enhanced capabilities such as a higher performance processor, cache memory, hardware power management, and two PCMCIA slots. In addition to a Flash memory card, another PCMCIA device can be supported in a modular fashion, such as a radio. Several converging design decisions that have were for VuMan 2R and VuMan 3 contributed to shortening of their detailed design and implementation phases, as part of that work has been overlapped.

A methodology is being developed for analyzing the power consumption of mobile computers. This methodology could be a precursor to system software which learns about user habits and adapts the power management strategy. Mobile computers have constraints that their desktop predecessors do not, especially in the domains of size, weight, and power. The power consumed by a mobile computer is a key constraint, because the power determines the amount of batteries needed, which is a major factor in the minimum volume and weight of the system. For example, in the VuMan 1, battery weight was 20% of the system weight; in the VuMan 2, it was 50% of the system weight; and in Navigator 1, it was 70% of the system weight.

Last updated on 19 July 1997