To demonstrate functional integration and payload transportation enabled by MR-LF, experiments were performed using procedures
similar to the locomotion experiments. To demonstrate bidirectionality, the rotation direction of the actuator magnet was reversed mid-test. Obstacle traversal was demonstrated in a larger channel (ID: 25.4 mm) with an obstruction made from a clear adhesive gel-like putty (Clear Museum Gel, Quakehold!). Obstacle pushing was performed using a robot with a mass of 3 g and a cylindrical PLA obstacle with a mass of 15 g. Untethered drug delivery was demonstrated using food dye in a gelatin capsule that was placed within a perforated rigid compartment of an MR-LF. The demonstration showing catheter navigation was performed by injecting food dye through flexible tubing (TND80-010, Component Supply Co.) that was cast through the center of an MR-LF-S. Water tests were performed at 36 °C and involved robots moving within a thin, flexible plastic tubing (LDPE Poly Tubing, ID: 16 mm, thickness: 0.05 mm) suspended in an open configuration between two supports. For the demonstrations in Figure
\ref{570124}A-D, the actuator magnet was located at a fixed position, and rotation occurred in the +z or -z direction. For the demonstrations in Figure
\ref{570124}E-F, the robot was turned by controlling the position and orientation of the actuator magnet in the x-z plane at y
a = 11 cm such that the rotation axis was approximately perpendicular to the robot’s path.
Y.L.K. acknowledged support from the 3M Non-Tenured Faculty Award; National Institutes of Health (NIH) NIBIB Trailblazer Award (Grant No. 1-R21-EB029563-01) and the Utah NASA Space Grant Consortium Faculty Research Seed Funding Awards. Y.L.K and O.S.P. acknowledged support from the National Science Foundation (NSF) under Emerging Frontiers in Research and Innovation (EFRI) Program (Grant No. EFRI 1830958).
Y.L.K. is an inventor on multiple patents and patent applications describing 3D printing technologies, including active electronic materials and devices, and multifunctional hybrid devices and structures. Y.L.K. is also an inventor of gastric‐resident systems, including gastric‐resident electronics. T.E.G. is an inventor on a patent application describing a 3D printing technology. Y.L.K. and T.E.G. are inventors of the patent application for this work. All other authors declare no conflict of interest.