Development of Intention Indicator Device for a Two-Wheeled Mobile Robot

In small ground vehicles, two-wheel steering mechanisms yield in-situ rotation, precise and quick movement are widely used. Such a ground vehicle can easily collide with the people around it without an indicator of how it will move. To prevent collisions when driving on public roads, action indicating devices such as blinkers and braking lights mounted on vehicles are effective. This paper developed a new intention indication device for a future two-wheeled steerable mobile robot in urban areas. We adopted a round ring shape with an RGB LED strip light for the mobile robot intention indicator. By adopting RGB LED strip lights, we can express various colors and complex flashing patterns. To determine colors and flashing patterns that are easy to understand the mobile robot's intention, we conducted a sensitivity evaluation experiment on about 50 subjects. As a result, we were able to determine colors and flashing patterns suitable for a two-wheeled steering type mobile robot. A reaction time acquisition experiment confirmed the effectiveness of the proposed intention indicator for the mobile robot.