Design of shape-lockers and distal disks.

(A) Shape-locker design (exploded view). (B) Assembly of two facing shape-lockers (the first shape-locker belongs to the leader, whereas the second shape-locker belongs to the follower), which highlights the π rad angular shift between them. (C) Distal disk design (exploded view and assembly). The seven different components needed to build the entire probe (apart from the commercial items) are labeled as C1 to C7.