| 摘要 |
A device is provided including a first linkage system and a second linkage system. Each linkage system may include an upper support, a lower support, and a cross bar linkage including a first cross bar and a second cross bar. The first cross bar may be configured with a first end pivotally coupled to a first end of the lower support and a second end pivotally coupled to a second end of the upper support. The second cross bar may be configured with a first end pivotally coupled to a second end of the lower support and a second end pivotally coupled to a first end of the upper support. The device may also include a flexible bridging platform coupled to one of the upper support or the lower support of the first linkage system and coupled to the upper support of the second linkage system, and a flexible strut coupled to the lower support of the second linkage system. |
