Robotic capsule endoscope for minimally invasive surgical procedures, micro-patterned treads for friction enhancement of a robotic capsule endoscope in a biological environment, and process for fabrication of micro-treads
Micro-patterned treads for endoscopes are disclosed. In an embodiment, the treads include a micro-patterned surface and a roller engaging surface. Micro-patterned tread bearing robotic capsule endoscopes are disclosed. In one embodiment, the endoscope includes a housing, a motor, a geared drive, rollers, and at least one micro-patterned tread. Methods of fabricating closed loop treads are disclosed. In an embodiment, a method includes forming a solid layer of PDMS on one side of double-sided tape and wrapping a micro-patterned PDMS strip together with the other side of the double-sided tape. In another embodiment, a method includes forming a timing belt PDMS strip on one side of double-sided tape and a micro-patterned PDMS strip together with the other side of the double-sided tape.
1. A micro-patterned tread for a robotic capsule endoscope, the micro-patterned tread comprising:
a first side and a second side of the micro-patterned treat tread, the first side and the second side in opposition to one another;
a micro-patterned surface disposed on the first side in a direction extending outwardly from the second side;
a roller engaging surface disposed on the second side in a direction extending outwardly from the first side;
a first layer having the first side with the micro-patterned surface thereon, the first layer including a molded surface and a non-molded surface in opposition to one another, the molded surface including PDMS molded to form the micro-pattern surface, wherein the first layer is formed in a first mold;
a second layer having the second side with the roller engaging surface thereon, the second layer including a molded surface and a non-molded surface in opposition to one another, the molded surface including PDMS molded to form the roller engaging surface, wherein the second layer is formed within a second mold; and
an adhesive configured to join the first layer and the second layer together with the non-molded surface of the first layer and the non-molded surface of the second layer joined together so as to dispose the first side and the second side in opposition to one another.
2. The tread of claim 1 , wherein the tread has a micro-pattern of pillars with a diameter of about 140 μm.
3. The tread of claim 2 , wherein the pillars of the tread have a height of 70 μm.
4. The tread of claim 3 , wherein the pillars of the tread are circular.
5. The tread of claim 4 , wherein the pillars of the tread are equally spaced with a center-to-center distance of 245 μm.
6. The tread of claim 2 , wherein the pillars of the tread are circular.
7. The tread of claim 2 , wherein the pillars of the tread are square.
8. The tread of claim 2 , wherein the pillars of the tread are diamond.
9. The tread of claim 2 , wherein the pillars of the tread are equally spaced with a center-to-center distance of 245 μm.
10. The tread of claim 9 , wherein the pillars of the tread form gaps of a distance of about 105 μm therebetween.
11. The tread of claim 2 , wherein the pillars of the tread form a gap to diameter ratio of about 0.75.
12. The tread of claim 1 , wherein the tread has a micro-pattern of pillars with each pillar having a diameter of less than 200 μm.
13. The tread of claim 12 , wherein the pillars have a height to width aspect ratio of 1:2.
14. The tread of claim 1 , wherein the tread has a micro-pattern of pillars with each pillar having a height of about 70 μm.
15. The tread of claim 1 , wherein the pillars have a height to width aspect ratio of 1:2.
16. The tread of claim 1 , wherein the pillars have a height to width aspect ratio within a range of about 1:4 to about 2:1.
17. The tread of claim 1 , wherein the first side comprises PDMS.
18. The tread of claim 1 , wherein the second side comprises PDMS.
19. The tread of claim 1 , wherein the second side comprises a smooth layer of PDMS configured to frictionally engage rollers of the robotic capsule endoscope.
20. The tread of claim 1 , further comprising a titanium layer disposed on the non-molded surface of the first layer.
21. The tread of claim 20 , wherein the adhesive comprises a double sided tape between the titanium layer and the non molded surface of the second layer.
22. The tread of claim 20 , wherein the second side of the tread includes a timing belt and wherein the timing belt is configured to engage timing pulleys of the robotic capsule endoscope.
23. The tread of claim 1 , further comprising a tread seam configured to join opposing ends of the tread to one another so as to form a continuous surface along the first side and a continuous surface along the second side.