| 摘要 |
A device comprising a flexible elongate member having proximal (72) and distal extremities (41). A flexible coil spring is provided having proximal and distal extremities. The proximal extremity of the coil spring is secured to the distal extremity of the flexible elongate member. A shape memory alloy element (46) is disposed within and extends substantially longitudinally of the coil spring (36). The shape memory alloy element has a memory which makes it attempt to assume a straight shape when an electrical current is passed through and heats the same. The shape memory alloy element (46) also has a stiffness which increases with the temperature of the element. An electrical current supply (67) is provided for supplying an electrical current to the shape memory alloy element for changing the stiffness of the shape memory alloy element to thereby stiffen the distal extremity of the flexible elongate member. |
