| 摘要 |
A system for providing an input signal, comprises an element (M, 1 ) controllable by a user by means of interaction with a user's limb, which system comprises a sensor ( 5,6 ) capable of detecting the presence of a limb placed over at least part of the element (M, 1 ), timing means ( 2 ) for determining the length of a time during which the limb is present and means ( 11,9,7,8 ) of generating an alarm signal if the length of time exceeds a threshold value. The alarm signal can be used to effect discontinuation of the presence of the limb. |
