Inserting Plugs into Electric Sockets in Visually Disturbed Situations

Abstract

Sometimes people experience difficulty in inserting or unplugging a plug into a wall socket. It is important to design sockets and plugs with low human error and high insert speed in the plug insertion process. There are a variety of socket types. Each type of socket can only accommodate a compatible plug. Depending on the type of socket, the number of plug pins, the location and angle of the plug pins are also different. In this study, plug-in speeds in various situations were measured for four types of plug-socket assembly. When the socket was installed below or above the eye level rather than eye level, the plug-in speed was significantly slowed down. Plug insertion under dark lighting required significantly longer time than plug insertion under bright lighting. These can be interpreted as a result of the condition that the dark environment and obstruction of the eye-gaze would have made the movement time longer. The larger the number of pins included in the plug, the longer the plug insertion time. In addition, the plug insertion time was shorter when a plug composed of round pins was used rather than flat rectangular pins. When designing a plug, it is desirable to reduce the number of pins as much as possible, and to design the shape of the pin to be round to facilitate plug insertion. This design will allow the plug to be easily inserted even in a visually disturbed environment, and will be a useful design especially for the elderly with visual impairments.