In shared virtual environments, multiple users can perform complex manipulations collaboratively, while receiving haptic feedback from the environment and other users. In single-user systems, dynamic assistance functions were shown to improve task performance; however, little is known about their effect on user perception. In this paper, state-of-theart assistance functions presented for single-user systems are transferred to a multi-user system. Aiming to assess the effect of these assistance functions on objective and perceived task performance, as well as on user comfort, an experimental user study has been conducted with a typical collaborative haptic interaction task. The analysis of the results showed that some assistance functions significantly improved movement coordination compared to unassisted execution of the task. The results further indicate that the effects of an assistance function on subjective performance and comfort ratings depend on the level of movement control that the user is afforded. The results of this study provide useful information for the design of effective and comfortable assistance functions.    «

In shared virtual environments, multiple users can perform complex manipulations collaboratively, while receiving haptic feedback from the environment and other users. In single-user systems, dynamic assistance functions were shown to improve task performance; however, little is known about their effect on user perception. In this paper, state-of-theart assistance functions presented for single-user systems are transferred to a multi-user system. Aiming to assess the effect of the...    »