| 摘要 |
<p>A platform with a roller on an underside and a sheet, extendable by a movement of such roller, such sheet extending to a top of the platform, where upon a rotation of the roller coinciding with a movement of the platform, the sheet moves in a direction opposite to the movement of the platform and in an approximately equal distance to the movement of the platform, so that an object being moved onto the platform is pulled onto the platform by the sheet when the platform is moved under the object, and so that an absolute position of the object relative to the ground is maintained while the object is moved onto the platform..</p> |
