Magnetic-anchored robotic system

1. A robotic actuator, comprising:

an internal anchor that is adapted to be inserted into a body via an entrance port, positioned inside the body, and magnetically coupled with an external anchor positioned outside the body; and

an instrument assembly that is adapted to be inserted into the body via the entrance port, wherein the instrument assembly is secured to the internal anchor, the instrument assembly comprising:

an arm having a serial arrangement of a proximal segment, a middle segment, and a distal segment, wherein:

a proximal end of the proximal segment is pivotally secured by a joint to the internal anchor in such a way that the proximal segment is configurable to pivotally move relative to the joint according to the joint's pivotal connection of the proximal end and the internal anchor;

each of the proximal segment, middle segment, and distal segment having an elongated hollow body; and

the middle segment is provided between the proximal and distal segments, the middle segment configurable to rotate relative the proximal segment, the rotation of the middle segment being a rotation relative to an axis formed by the middle segment;

an end-effector, the end-effector having a wrist and an instrument, the instrument secured by the wrist to a distal end of the distal segment via the wrist in such a way that the instrument is configurable to pivotally move relative to the wrist according to the wrist's pivotal connection of the distal end and the instrument;

a plurality of actuators distributed on the arm, wherein the elongated hollow body of the proximal segment houses at least one of the actuators, wherein each of the plurality of actuators comprises a multi-axis robotic joint, and wherein each of the plurality of actuators provides multiple degrees of movement via multiple axes relative to the internal anchor; and

one or more sensors provided on the instrument assembly, the one or more sensors configured to detect a resisting force resulting from the pivotal movement of the proximal segment relative to the joint, the rotational movement of the middle segment, or the pivotal movement of the instrument relative to the wrist, the one or more sensors providing a corresponding haptic feedback to a manipulator when a resisting force is detected;

wherein the pivotal movement of the proximal segment relative to the joint, the rotational movement of the middle segment, and the pivotal movement of the instrument relative to the wrist are each controllable by the manipulator.

2. The robotic actuator of claim 1 , wherein the actuators each have a rotation axis oriented in a same direction.

3. The robotic actuator of claim 2 , wherein the actuators are distributed along the rotation axis.

4. The robotic actuator of claim 3 , wherein the plurality of actuators includes a first actuator proximal to the internal anchor, a second actuator proximal to the wrist, and a third actuator disposed between the first and second actuators.

5. The robotic actuator of claim 4 , wherein

the first actuator is configurable to provide the pivotal movement of the proximal segment relative to the joint,

the second actuator is configurable to provide the pivotal movement of the instrument relative to the wrist, and

the third actuator is configurable to provide the rotational movement of the middle segment.

6. The robotic actuator of claim 5 , further comprising a fourth actuator, the fourth actuator configurable to adjust a length of the middle segment relative to a distal end of the proximal segment.

7. The robotic actuator of claim 6 , wherein the first and third actuators are adjacent to each other.

8. The robotic actuator of claim 5 , further comprising a fifth actuator that provides movement about a second axis of the end-effector with respect to the body of the instrument.

9. The robotic actuator of claim 7 , further comprising a sixth actuator that provides movement about a third axis of the end-effector with respect to the body of the instrument.

10. The robotic actuator of claim 9 , wherein the second, fifth and sixth actuators are adjacent to each other.

11. The robotic actuator of claim 9 , wherein

the sixth actuator is coupled to a bevel gear, and

the second and fifth actuators are each coupled to a worm gear.

12. The robotic actuator of claim 5 , further comprising mechanical element coupled between the second actuator and the end-effector, the mechanical element providing a speed reduction or force multiplication to the second actuator.

13. The robotic actuator of claim 12 , wherein the mechanical element is a planetary gear.

14. The robotic actuator of claim 12 , further comprising a pulley coupled between the mechanical element and the end-effector.

15. The robotic actuator of claim 14 , further comprising a second mechanical element coupled between the pulley and the end-effector, the second mechanical element including a gear ratio that increases torque applied to the end-effector by the second actuator.

16. The robotic actuator of claim 5 , wherein the third actuator is coupled to a threaded rod having a carrier engaged thereon, the carrier travelling along the threaded rod when an output of the third actuator rotates.

17. The robotic actuator of claim 16 , wherein the third actuator includes one or more linear actuators.

18. The robotic actuator of claim 5 , wherein the first actuator is coupled to a worm gear.

19. The robotic actuator of claim 18 , wherein the worm gear is coupled to a gear.

20. The robotic actuator of claim 19 , wherein the worm gear and the gear are coupled via an approximately 90 degree intersection.

21. The robotic actuator of claim 1 , wherein the robotic actuator is generally cylindrical in shape.

22. The robotic actuator of claim 21 , wherein a diameter of the cylinder is 21 mm or less.

23. The robotic actuator of claim 22 , wherein a length of the cylinder is 200 mm or less.

24. The robotic actuator of claim 1 , wherein the instrument assembly and the internal anchor are adapted to be coupled together before insertion into the body via the entrance port.

25. The robotic actuator of claim 24 , wherein the instrument assembly is fixed to the internal anchor via the joint before insertion into the body via the entrance port.

26. The robotic actuator of claim 1 , further comprising a circuit board.

27. The robotic actuator of claim 26 , wherein the circuit board includes driver circuitry.

28. The robotic actuator of claim 26 , wherein the circuit board includes a network interface.

29. The robotic actuator of claim 26 , wherein the circuit board is flexible.

30. The robotic actuator of claim 26 , wherein the circuit board is disposed adjacent to an inner wall of a housing of the instrument assembly.