Fig. 5: Robotic navigation in 3D ex vivo tissues and multi-MMD deployment.
From: Synthetic X‑ray‑driven tracking and control of miniature medical devices
a, A 3D reconstruction of vascular pathways via intra-vascular contrast agent injection and multi-angle imaging. b, A reconstructed lumen path and planned magnet path for targeted robotic deployment. c., MMD deployment under low-contrast imaging conditions. Left: imaging-angle configuration. Top row insets: magnified MMD views. Bottom row insets: segmentation outputs with confidence scores. d, Real-time MMD tracking under imaging-angle misalignment. The segmentation neural network trained on fixed-angle MMD imagery demonstrates robust generalization to appearance variations induced by 3D rotational misalignment. Left: imaging-angle configuration. Top row insets: magnified MMD views. Bottom row insets: segmentation outputs with confidence scores. e, The path planning for multi-MMD deployment. f, Real-time multi-MMD deployment and tracking. Scale bars represent 10 mm. The mean MMD translation speed and locomotion distance are denoted by \({v}_{{\rm{r}}}\) and \({l}_{{\rm{r}}}\), respectively. Using a rotating 30-mm N45 cubic magnet, the magnetic torque and force range from 2.0 μNm to 13.2 μNm and from 0.1 mN to 0.4 mN, respectively. Soft MMD dimensions of 1.5 mm in diameter and 5.0 mm in length.
