Fig. 4. Matching target shapes by a series of deform and latch operations.

(A) An initially flat beam is first deformed to match the slit orientation in the object and then further actuated to allow picking up the object. To match the slit orientation, the first segment of the beam is twisted and latched by −20° around the z axis. The device is then lowered so that the first segment is inside the object. The second joint then is softened and twisted to an angle of +20°, thus preventing the device from being pulled out, and hence allowing the object to be picked up. See movie S2. (B) In this example, bending on two axes is required to match the slit on the target. The slide on the green object is rotated by −25° and 25° with respect to the x and z axes. The beam was initially flat and was aligned with the z axis. The device was first bent and latched with an angle of 25° using the first joint and then twisted through the third joint with an angle of 25°. Throughout the second deformation, the first joint is locked and does not deform. Once the device configuration matched the object slit orientation, the device was lowered, slotting in as required. (C) Frames from movie S2 showing the insertion of an initially flat device through a series of differently oriented slits. The initially flat device successfully passed the apertures by performing a series of local twisting and shape fixation.