In this paper, we propose a unique robot that moves on a handrail installed at corridors of buildings like hospitals. The robot guides the guests of the building. Because it moves on the handrail along the corridor, it naturally moves along the corridor without conflicting other people and needs less cost for estimating its position compared with human-sized mobile robots. We propose a method to control this robot so that it precedes a few steps before the person to be guided. We examine two methods: one is a method to keep a fixed distance from the person, and the other one is a method where the robot keeps moving slowly even when the robot and the person is distant. From the experiment, the latter method was more efficient than the former method.

We investigated the effect of height of a robot on comfortableness of spoken dialog with the robot. We created a robot that could change the height continuously, and carried out dialog experiment with 18 subjects changing the robot's height. From the experimental result revealed the two observations: the "comfortable height" of a robot was lower than the eye height of a subject, and the comfortableness of dialog reduced when the height of the robot changed by 200 mm from the comfortable height.