Abstract
Many advances in computer aided design (CAD) have been made to support more rapid product development. One key area that has not been adequately addressed is in the area of rapid model creation for the exploration and communication of initial or conceptual design ideas. The human computer interface for current CAD systems remains tedious, detail oriented, and time consuming, and because of this CAD cannot be utilized effectively in the early stages of a design project. This is a considerable deficit, since the visualization of spatial models at the most crucial (concept) stage of design would be of great value. It is during this stage that most decisions controlling overall product performance limits are made. To address this need, a new approach to shape modeling has been proposed, which incorporates a virtual reality (VR) design interface. The initial interface specification includes multi-modal input/output consisting of speech input, auditory output, spatial (glove) input, and three dimensional stereographic display output.
It is desirable to augment this interface with an additional output mode in the form of haptic or touch sensation to more efficiently and intuitively interact with concept solid models. The hypothesis is that the addition of this output mode will (i) increase the efficiency in complex geometry creation, and (ii) aid in the understanding and exploration of a wide variety of design concepts. The desire for haptic feedback is shared by many developers of VR environments, for a wide variety of applications. Thus, there has been a recent increase in research interest in this area. The development of haptic feedback systems remains a multi-disciplinary challenge as an effective system must address perceptual, comfort, control, and mechanical issues that arise from the closely coupled human-machine dynamics present in a haptic feedback system. In this paper, we evaluate the general approaches for haptic feedback design in light of CAD tasks. Inherent limitations to the various approaches are identified and evaluated. The limitations are compared with the device complexity and value added for CAD operations.
