Virtual Reality Services Research Articles

Mobile virtual reality services

This paper addresses the capability needed in a telecommunication system to support mobile access to real-time sights and sounds of a complex environment defined as a virtual reality service (VRS) episode. The constant growth in data transmission rates and the innovative advances in the development of terminal and networking equipment are paving the way for the provision of a VRS and the creation of VRS episodes in the near future. These advancements are necessary for transmitting, transporting, and receiving data at super-high transmission rates for establishing VRS episodes. This paper describes a mobile VRS environment in general and the core architecture and describes the various entities employed to perform a VRS episode setup task. The proposed VRS architecture is in full harmony with preceding generations of all-IP multimedia networks currently under study in the 3rd Generation Partnership Project (3GPP), the 3rd Generation Partnership Project 2 (3GPP2), and the International Telecommunication Union (ITU).

Effect of Servo-System on Haptic Interface.

Multi-media services such as audio and visual media are advanced rapidly. In addition to them, physical force information is expected as the next service, which may realize virtual reality service. Many reserches concerning the haptic interface as the force display have been reported. However, as they have not been studied specially from the control view point, control problems have not been clarified systematically. The purpose of this paper is to clarify the control problems of the haptic interface systematically, which includes not only the realization of the force display but also its stability and limitation. In this paper, two major control algorithms are investigated. The first type is the position control type, which realizes the position corresponding to user's force in consideration of the virtual environment dynamics. The second type is the force control, which realizes the force corresponding to operator's finger position. The following results are obtained. (1) Position control type: This type can realize the stable system for applied force. However, the force display does not show sharp linearity because it does not consider the force balance between the operator's finger and the interface. As the virtual environment dynamics must be used for realizing the Free Space, the unstable phenomenon occurs the continuation of the dynamic parameter is not guaranteed between the Free space and the Constrained Space. (2) Force control type: This system shows excellent performance as the force display because it actually generates the force by itself. However, the unstable phenomenon occurs when the force display becomes larger in relation to the user's finger reflecting force.