Space-division multiplexing (SDM) technology is a promising candidate to achieve massive parallelism in optical fiber cables and overcome the capacity limitation of the conventional single-mode fiber (SMF). Among the several kinds of SDM fiber, a weakly coupled multicore fiber (MCF) is advantageous in that it can be easily upgraded for use in existing equipment and requires no complex signal processing for optical multi-input multi-output (MIMO). In this article, we discuss the progress and standardization activity of MCF technologies from the viewpoint of accelerating the practical application of SDM technology. We first describe the possible application areas of SDM fibers and then show the recent progress of the essential technologies to construct the MCF link: the MCF itself, its splicing and connectorization, and the input/output techniques. We also discuss the availability and deployability of MCF as a large-capacity transmission medium and detail the progress on establishing a new international standard for SDM technology, which includes both historical progress and more recent endeavors on the standardization of optical fiber cables and SDM technology in International Telecommunication Union Telecommunication Standardization Sector (ITU-T) and International Electrotechnical Commission (IEC). We close with a summary of MCF technology and its standardization activity with an eye to next-generation transmission systems and the long-term development of ultralarge capacity SDM transmission technology.

This paper proposes an alternative predictive display method for a network teleoperation with the time delay. In general, the communication time delay in a teleoperation system disturbs not only the stability of the robotic system but also that of the human controlled loop and it leads to a decrease of the reality of the operation. To prevent this, several predictive display approaches based on the virtual environment models have been proposed recently. But, they cannot work well without the precise virtual environment model and, in addition, it is a complicated and time-consuming task to construct the precise kinematic and dynamic model of the general various working environment. We design a new predictive display method of the motion and the force information for a general network teleoperation without using the virtual environment model. The proposed method is basically developed from the superimposed display of the predictive image and the real image of the slave site. The major contribution of this method is to provide the predictive motion and force information to the human operator without using any virtual model of the real environment even in the constrained space as well as in the free space. It enables to construct the environment-independent and easily applicable teleoperation system in the field of the network robotics such as the tele-manipulation, tele-communication, home/hobby-use-network-teleoperation and so on. The proposed method is experimentally applied to a tele-manipulation system and the results illustrate the validity of the proposed approach.