Robotic linkage

1. A method comprising:

articulating a first link and a second link relative to each other about a pair of outer hinge portions on a first end of the first link and in mating engagement with a pair of inner hinge portions on a second end of the second link;

wherein each outer hinge portion comprises an outer ear extending in a first axial direction away from the first end of the first link, and an inner bearing surface substantially oriented in the first axial direction;

wherein each inner hinge portion comprises an inner ear extending in a second axial direction away from the second end of the second link, and an outer bearing surface positioned oriented in the second axial direction;

wherein, during the articulating, the outer bearing surfaces support the outer ears and the inner bearing surfaces support the inner ears.

2. The method of claim 1 , wherein each of the pair of outer hinge portions are diametrically opposed across the first link.

3. The method of claim 1 , wherein each of the pair of inner hinge portions are diametrically opposed across the second link.

4. The method of claim 1 , further comprising articulating the second link and a third link relative to each other about a pair of outer hinge portions on a first end of the second link in mating engagement with a pair of inner hinge portions on a second end of the third link.

5. The method of claim 4 , wherein:

articulating the first link and the second link relative to each other comprises articulating the first link and the second link relative to each other about a first axis of rotation, and

wherein articulating the second link and the third link relative to each other comprises articulating the second link and the third link relative to each other about a second axis of rotation perpendicular to the first axis of rotation.

6. The method of claim 1 , wherein articulating the first link and the second link relative to each other comprises sliding inner surfaces of the outer ears against outer surfaces of the inner ears.

7. The method of claim 1 , wherein articulating the first link and the second link relative to each other comprises sliding the outer ears against the outer bearing surfaces and sliding the inner ears against the inner bearing surfaces.

8. The method of claim 1 , wherein articulating the first link and the second link relative to each other comprises articulating the first link and the second link relative to each other by applying an actuation force to at least one of the first link and the second link.

9. The method of claim 8 , wherein applying an actuation force to at least one of the first link and the second link comprises tensioning an actuation tendon connected to at least one of the first link and the second link.

10. The method of claim 9 , wherein applying the actuation force to the at least one of the first link and the second link comprises tensioning the actuation tendon on a first side of a pulley coupled with at least one of the first link and the second link and around which the actuation tendon is at least partially wrapped and slackening the actuation tendon on a second side of the pulley.

11. The method of claim 9 , wherein tensioning the actuation tendon comprises drawing the tendon through a guide block positioned proximate at least one inner hinge portion of the pair of inner hinge portions.

12. The method of claim 9 , wherein tensioning the actuation tendon comprises drawing the tendon through a coil tube connected to one of the first and second links.

13. The method of claim 1 , wherein articulating the first link and the second link relative to each other comprises articulating the first link and the second link relative to each other through an angular range of +/−30 degrees.

14. A method of assembling an elongated instrument, comprising:

positioning a pair of outer hinge portions of a first end of a first link in mating engagement with a pair of inner hinge portions of a second end of a second link;

wherein positioning the pair of outer hinge portions in mating engagement with the pair of inner hinge portions comprises:

placing an outer ear of the outer hinge portion in sliding engagement with an outer bearing surface of the inner hinge portion, and

placing an inner ear of the inner hinge portion in sliding engagement with an inner bearing surface of the outer hinge portion.

15. The method of claim 14 , wherein positioning the pair of outer hinge portions in mating engagement with the pair of inner hinge portions comprises placing an inner surface of the outer ear in sliding contact with an outer surface of the inner ear.

16. The method of claim 14 , further comprising connecting one or more actuation tendons to a respective one or more of the first link and the second link.

17. The method of claim 14 , further comprising routing at least one actuation tendon through a passage formed in at least one of the first link and the second link.

18. The method of claim 14 , further comprising routing at least one actuation tendon through a coil tube extending through a passage formed in at least one of the first link and the second link.

19. The method of claim 14 , further comprising routing at least one actuation tendon through a passage formed in one or more guide blocks each connected to a respective one of the first link and the second link.

20. The method of claim 14 , further comprising placing an imaging device in a lumen extending longitudinally through the first link and the second link.