Coupler to attach robotic arm to surgical table
An apparatus can include a coupler for coupling a robotic arm to a surgical table having a table top on which a patient can be disposed. The coupler can include a first portion configured to couple to a surgical table and a second portion configured to couple to a robotic arm. The second portion may include a post that may translate into the first portion. The first portion may comprise a locking mechanism having one or more stages to constrain movement of the second portion relative to the first portion in six degrees of freedom. The coupler can thus provide secure coupling of the robotic arm to the surgical table.
1. A coupler for coupling a robotic arm to a surgical table, the coupler comprising:
a first portion configured to couple to a surgical table;
a second portion configured to couple to a robotic arm, the second portion having a post configured to translate along a first axis of the first portion to couple the second portion to the first portion; and
a locking mechanism configured to transition a coupling between the first portion and the second portion between a locked position and an unlocked position, wherein the locking mechanism is coupled to an interior cavity of the first portion and comprises a holder, a ball bearing assembly, a cam, and wherein the holder and the ball bearing assembly are configured to engage the post, and a translation of the cam along the first axis causes the holder to translate the post along the first axis between the locked position or the unlocked position, and in the locked position, movement of the first portion relative to the second portion in six degrees of freedom is constrained.
2. The coupler of claim 1 , wherein the cam is a first cam, and the locking mechanism further comprises a second cam positioned within the interior cavity of the first portion, and wherein a translation of the first cam and the second cam along the first axis causes the holder to translate the post along the first axis to the locked position or the unlocked position.
3. The coupler of claim 2 , wherein each of the first cam and the second cam are face cams having a variable cam surface profile configured to adjust a translation function or an axial force function of the locking mechanism.
4. The coupler of claim 1 , wherein the holder comprises a receiving cavity dimensioned to receive the post, and wherein the interior cavity of the first portion comprises an interior contact surface and the post comprises an exterior contact surface, and a ball of the ball bearing assembly contacts the interior contact surface and the exterior contact surface in the locked position.
5. The coupler of claim 1 , wherein the locking mechanism further comprises a biasing member configured to apply a biasing force to the ball bearing assembly.
6. The coupler of claim 1 , wherein the first portion comprises an axially oriented groove along an outer surface, and the second portion comprises a kinematic mount configured to mate with the groove when the second portion is coupled to the first portion, and where the kinematic mount and the groove are dimensioned to constrain translation or rotation of the first portion with respect to the second portion.
7. The coupler of claim 1 , wherein the first portion further comprises an alignment opening, and the second portion comprises an alignment protrusion, the alignment protrusion having an asymmetrical shape configured to mate with the alignment opening in a single orientation and prevent misalignment of the first portion with respect to the second portion.
8. The coupler of claim 1 , wherein the post of the second portion is dimensioned to surround the first portion to constrain translation of the first portion with respect to the second portion along the first axis.
9. The coupler of claim 1 , wherein the locking mechanism further comprises a shaft and the cam is coupled to a bushing, wherein the cam and the bushing are configured to translate along the shaft to vary a contact force of the ball bearing assembly against the post between the locked position and the unlocked position.
10. The coupler of claim 1 , further comprising an electrical interface between the first portion and the second portion, wherein the electrical interface is operable to provide power to a motor for driving the locking mechanism.
11. A coupler for coupling a robotic arm to a surgical table, the coupler comprising:
a first portion having a first end configured to couple to a surgical table and a second end, the second end defining an opening to an interior cavity within the first portion;
a second portion configured to couple to a robotic arm, the second portion having a post configured to be received within the interior cavity and translate along the first axis of the first portion to couple the second portion to the first portion;
a locking mechanism having a holder that translates within the interior cavity along the first axis of the first portion to engage the post, a ball bearing assembly coupled to the holder, a first cam, and a second cam, and wherein a translation of the first cam and the second cam along the first axis causes the holder to translate the post along the first axis to the locked position or the unlocked position; and
a drive mechanism configured to drive an operation of the locking mechanism.
12. The coupler of claim 11 , further comprising a connection sensor configured to detect a coupling and a decoupling between the first portion and the second portion.
13. The coupler of claim 11 wherein the ball bearing assembly comprises a set of ball bearings positioned within the interior cavity of the first portion.
14. The coupler of claim 11 , wherein the holder comprises a receiving cavity dimensioned to receive the post, and positions the set of ball bearings around the post, and wherein a translation of the holder causes the set of ball bearings to contact an exterior contact surface of the post and an interior contact surface of the interior cavity in the locked position.
15. The coupler of claim 11 , wherein each of the first cam and the second cam are face cams having a variable cam surface profile configured to adjust a translation function or an axial force function of the locking mechanism.
16. The coupler of claim 11 , wherein the locking mechanism further comprises a biasing member configured to apply a biasing force to the ball bearing assembly.
17. The coupler of claim 11 , wherein the first portion comprises an axially oriented groove along an outer surface, and the second portion comprises a kinematic mount configured to mate with the groove when the second portion is coupled to the first portion, and where the kinematic mount and the groove are dimensioned to constrain translation or rotation of the first portion with respect to the second portion.
18. The coupler of claim 11 , wherein the first portion further comprises an alignment opening, and the second portion comprises an alignment protrusion, the alignment protrusion having an asymmetrical shape configured to mate with the alignment opening in a single orientation and prevent misalignment of the first portion with respect to the second portion.
19. The coupler of claim 11 , wherein the drive mechanism comprises a handle.
20. The coupler of claim 11 , wherein the drive mechanism comprises a motor.