| 摘要 |
<p>methods and apparatus are provided through which in some implementations an apparatus includes three notable features and attributes: a first curved bar, at least one additional curved bar and a roller. In some implementations, a pad or beams may be placed under the roller. The first curved bar is attached to at least one additional curved bar by a first attachment system, a second attachment system and at least one additional attachment system. Each attachment system consists of a fastener bolt, a fastener nut and at least one spacer. The first curved bar is laterally spaced from the at least one additional curved bar by the at least one spacer of the first, second and at least one additional attachment systems. The first curved bar and the at least one additional curved bar and the first, the second and the at least one additional attachment systems form a support assembly which is movably connected to the roller by a flexible connecting device.</p> |
