摘要 |
<p>An extendible sheet member is configurable between first and second states. The first state is a coiled state (1.1) in which the member is coiled substantially parallel to a first axis and the second state is an extended state (1.2) in which the member extends substantially parallel to a second axis at some angle to the first axis. The member is made wholly or in part from a material or materials which give rise to internal stresses upon extension, these stresses acting at some angle to the second axis such as to bias the member to the second state. In many embodiments these stresses are produced by fibres which form part of the structure of said member. Said member is preferably reversibly configurable between said first and second states.</p> |