Jointed control platform

1. A medical device comprising:

a chassis comprising a pivotal support, the pivotal support defining a first axis of rotation;

an elongate tube having a first end coupled to the chassis and a second end opposite the first end;

an end effector coupled to the second end of the elongate tube;

an axle having a first end, a second end opposite the first end, and a second axis of rotation defined between the first end of the axle and the second end of the axle,

wherein the axle is supported by the pivotal support and is free to rotate around the first axis of rotation, and

the second axis of rotation is perpendicular to the first axis of rotation;

a first control arm coupled to the first end of the axle and free to rotate around the second axis of rotation; and

a second control arm coupled to the second end of the axle and free to rotate around the second axis of rotation independently of the first control arm.

2. The medical device of claim 1 , wherein:

the axle further comprises a first pin and a second pin opposite the first pin; and

the axle is supported by the pivotal support at the first pin and the second pin.

3. The medical device of claim 1 , wherein the first axis of rotation is equidistant from the first control arm and the second control arm.

4. The medical device of claim 1 , wherein the first control arm and the second control arm are the same length.

5. The medical device of claim 1 , further comprising a first control point and a second control point on the first control arm, and a third control point and a fourth control point on the second control arm, the axle being between and spaced apart from the first, second, third, and fourth control points.

6. The medical device of claim 5 , wherein the axle is equidistant from the first, second, third, and fourth control points.

7. The medical device of claim 5 , further comprising:

a first drive element, a first end of the first drive element coupled to the first control point, and a second end of the first drive element opposite the first end of the first drive element coupled to the end effector to control a first motion of the end effector;

a second drive element, a first end of the second drive element coupled to the second control point, and a second end of the second drive element opposite the first end of the second drive element coupled to the end effector to control a second motion of the end effector;

a third drive element, a first end of the third drive element coupled to the third control point, and a second end of the third drive element opposite the first end of the third drive element coupled to the end effector to control a third motion of the end effector; and

a fourth drive element, a first end of the fourth drive element coupled to the fourth control point, and a second end of the fourth drive element opposite the first end of the fourth drive element coupled to the end effector to control a fourth motion of the end effector.

8. The medical device of claim 7 , wherein:

the first drive element and the second drive element form a first loop coupled to a first moving part of the end effector; and

the third drive element and the fourth drive element form a second loop coupled to a second moving part of the end effector.

9. The medical device of claim 8 , wherein:

the first moving part comprises a first pulley fixed to a first jaw of the end effector, and the first pulley translates rotational movement of the first loop about the second axis of rotation to the first jaw to actuate the first jaw in a first degree of freedom; and

the second moving part comprises a second pulley fixed to a second jaw of the end effector, and the second pulley translates rotational movement from the second loop about the second axis of rotation to the second jaw to actuate the second jaw in a second degree of freedom.

10. The medical device of claim 9 , wherein:

the first jaw and the second jaw are supported on a wrist pivot of the end effector; and

movement of the first drive element and the second drive element in a first direction about the first axis of rotation, and movement of the third drive element and the fourth drive element in a second direction about the first axis of rotation, different than the first direction, actuates the first jaw and the second jaw in a third degree of freedom.

11. The medical device of claim 1 , further comprising a first lever coupled to the axle such that an effort applied to the first lever causes the axle to rotate about the first axis of rotation.

12. The medical device of claim 1 , further comprising a first lever and a second lever, the first lever coupled to one of the first control arm and the second control arm, and the second lever coupled to the other one of the first control arm and the second control arm such that an effort applied to one of the first lever and the second lever causes the coupled control arm to rotate about the second axis of rotation.

13. The medical device of claim 12 , further comprising a first control point and a second control point on the first control arm, and a third control point and a fourth control point on the second control arm, wherein the first lever coupled to one of the first control arm and the second control arm, and the second lever is coupled to the other one of the first control arm and the second control arm such that a coupling point of the first lever to the one of the first control arm and the second control arm and a coupling point of the second lever to the other one of the first control arm and the second control arm both lie on the first axis of rotation when the first, second, third, and fourth control points are coplanar.

14. An apparatus comprising:

a proximal mechanism, an elongate tube, a distal component, and first, second, third, and fourth drive elements;

the distal component comprising a medical tool;

the elongate tube having a first end coupled to the proximal mechanism and a second end opposite the first end, the second end coupled to the distal component;

the proximal mechanism comprising a pivotal support, an axle, a first control arm, and a second control arm;

the pivotal support defining a first axis of rotation;

the axle comprising a first end and a second end opposite the first end, a second axis of rotation being defined through the first end of the axle and the second end the axle, the axle being supported by the pivotal support so that the axle is free to rotate in the pivotal support around the first axis of rotation, and the second axis of rotation is perpendicular to the first axis of rotation;

a first control point being defined on the first control arm, and a second control point being defined on the first control arm spaced apart from the first control point;

a third control point being defined on the second control arm, and a fourth control point being defined on the second control arm spaced apart from the third control point;

the first end of the axle being coupled to the first control arm between the first control point and the second control point, the second end of the axle being coupled to the second control arm between the third control point and the fourth control point, and the first control arm and the second control arm each being free to rotate around the second axis of rotation;

the first drive element being coupled between the first control point and the distal component;

the second drive element being coupled between the second control point and the distal component;

the third drive element being coupled between the third control point and the distal component; and

the fourth drive element being coupled between the fourth control point and the distal component.

15. The apparatus of claim 14 , further comprising:

a first drive input coupled to the axle at a first drive input coupling;

a second drive input coupled to the first control arm at a second drive input coupling, wherein the first control arm and the second drive input rotate relative to one another around the first axis of rotation at the second drive input coupling; and

a third drive input coupled to the second control arm at a third drive input coupling, wherein the second control arm and the third drive input rotate relative to one another around the first axis of rotation at the third drive input coupling.

16. The apparatus of claim 15 , wherein:

the first drive input comprises a first lever, and the first drive input coupling comprises a first sliding coupling;

the second drive input comprises a second lever, and the second drive input coupling comprises a second sliding coupling; and

the third drive input comprises a third lever, and the third drive input coupling comprises a third sliding coupling.

17. The apparatus of claim 14 , wherein:

the first drive element and the second drive element form a first loop with reference to a first moving part of the distal component; and

the third drive element and the fourth drive element form a second loop with reference to a second moving part of the distal component.

18. The apparatus of claim 14 , wherein:

the first drive element and the third drive element form a first loop with reference to a first moving part of the distal component; and

the second drive element and the fourth drive element form a second loop with reference to a second moving part of the distal component.