SPHERICAL LINKAGE TYPE SURGICAL ROBOTIC ARM

In order to reduce the calculation in robotic arm allocation, the invention provides a spherical linkage type surgical robotic arm, which includes a first curved bar having a first axis center and a second axis center, a second curved bar being equal to the first curved bar in length and having a third axis center and a fourth axis center, the third axis center in coincidence with the first axis center, a third curved bar having a fifth axis center and a sixth axis center and being pivoted to the second curved bar, and a fourth curved bar having a seventh axis center and an eighth axis center and being pivoted to the third curved bar and the first curved bar, thereby reducing the calculation burden and facilitating control and allocation.

DETAILED DESCRIPTION OF THE INVENTION

Referring toFIGS. 1-3, a spherical linkage type surgical robotic arm in accordance with a first embodiment of the present invention is shown turnable around a center of spherical rotation C. The spherical linkage type surgical robotic arm comprises a first curved bar11, a second curved bar12, a third curved bar13and a fourth curved bar14.

It is to be noted that the axle center described in this specification is a virtual axis about which an object is turned.

The first curved bar11has a first axis center11aand a second axis center11brespectively located at two opposite ends thereof and passed through the center of spherical rotation C.

The second curved bar12is of equal length relative to the first curved bar11, having a third axis center12aand a fourth axis center12brespectively located at two opposite ends thereof and passed through the center of spherical rotation C. Further, the third axis center12acoincides with the first axis center11a.

The third curved bar13has a fifth axis center13aand a sixth axis center13brespectively located at two opposite ends thereof and passed through the center of spherical rotation C. The third curved bar13is pivotally connected to the second curved bar12. Further, the fifth axis center13acoincides with the fourth axis center12b.

The fourth curved bar14has a seventh axis center14aand an eighth axis center14brespectively located at two opposite ends thereof and passed through the center of spherical rotation C. The fourth curved bar14is respectively pivotally connected to the third curved bar13and the first curved bar11. The seventh axis center14acoincides with the sixth axis center13b.The eighth axis center14bcoincides with the second axis center11b.

In addition to the condition that the first curved bar11and the second curved bar12have the same length, the third curved bar13and the fourth curved bar14can be made having the same length, simplifying the program operation in controlling the motion of every curved bar in the preferred embodiments of the present invention. More particularly, the second curved bar12and the third curved bar13can be made having the same length. In this embodiment, the first curved bar11, the second curved bar12, the third curved bar13and the fourth curved bar14have the same length, further reducing the calculation burden and shortening the calculation time.

In this embodiment, the spherical linkage type surgical robotic arm further comprises a first driving mechanism15and a second driving mechanism16. The first driving mechanism15is a combination of a motor and a speed reducer for driving an object to rotate, comprising a first driving shaft151connected to the first curved bar11and coincided with the first axis center11a. The second driving mechanism16comprises a second driving shaft161connected to the second curved bar12and coincided with the third axis center12a.Because the first driving shaft151and the second driving shaft161are respectively and directly connected to the first curved bar11and the second curved bar12, the number of component parts can be relatively reduced, thereby reducing the manufacturing cost and shortening the assembling time, and therefore the invention is cost-effective. Further, through the first driving mechanism15and the second driving mechanism16to control relative motion between the first curved bar11and the second curved bar12, the motion of the spherical linkage type surgical robotic arm is thus controlled.

It is to be noted that the curved bar length indicated herein means the shortest distance between the two centers of axis of each curved bar at the common sphere based on the center of spherical rotation C.

Referring toFIGS. 4 and 5, a spherical linkage type surgical robotic arm in accordance with a second embodiment of the present invention is shown. This second embodiment is substantially similar to the aforesaid first embodiment with the exception that this second embodiment further comprises an instrument bar17, a first proportional wheel18, a second proportional wheel19, and a flexible element21.

The instrument bar17comprises an operational axis center17apassed through the center of spherical rotation C. The instrument bar17is pivotally connected to the third curved bar13or fourth curved bar14. Further, the operational axis center17acoincides with the sixth axis center13bor seventh axis center14a.

The first proportional wheel18is fixedly connected to the first curved bar11and rotatable with the first curved bar11to let the second axis center11bpass through the wheel axle center of the first proportional wheel18.

The diameter of the second proportional wheel19is larger than the diameter of the first proportional wheel18. Further, the second proportional wheel19is fixedly connected to the instrument bar17and rotatable with the instrument bar17to let the operational axis center17apass through the wheel axle center of the second proportional wheel19.

The flexible element21is wound round the first proportional wheel18and the second proportional wheel19. In this embodiment, the flexible element21is a steel wire rope. However, this is not a limitation. It can also be a rope or belt.

In this embodiment, installation of the first proportional wheel18, the second proportional wheel19and the flexible element21achieves the effect of enabling the turning angle of the instrument bar17to be smaller than the turning angle of the fourth curved bar14without the condition of having the first curved bar11and the second curved bar12to be made equal in length. However, if the first curved bar11and the second curved bar12have the same length, it achieves the effect of shortening the calculation time. Further, the second curved bar12and the third curved bar13can also be made equal in length, enhancing the effects.

If the diameter of the second proportional wheel19is twice the diameter of the first proportional wheel18under the condition that the first curved bar11, the second curved bar12, the third curved bar13and the fourth curved bar14have the same length, the contained angle between the instrument bar17and the third curved bar13and the contained angle between the instrument bar17and the fourth curved bar14can be kept equal.

During the operation of the second embodiment of the present invention, due to the installation of the first proportional wheel18and the second proportional wheel19, there is a turn proportional relationship between the instrument bar17and the first curved bar11, and therefore the turning angle of the surgical instrument mounted at the instrument bar17can be reduced, bringing to the surgeon better readability of the data being displayed on the surface of the surgical instrument than conventional mechanical arm designs.

Referring toFIG. 7, a spherical linkage type surgical robotic arm in accordance with a third embodiment of the present invention is shown turnable about a center of spherical rotation. The spherical linkage type surgical robotic arm comprises: a first curved bar31, a second curved bar32, a third curved bar33, a fourth curved bar34, a ground bar35, an instrument bar36, a first proportional wheel37, a second proportional wheel38and a flexible element39.

The first curved bar31has a first axis center31aand a second axis center31brespectively located at two opposite ends thereof and passed through the center of spherical rotation C.

The second curved bar32has a third axis center32aand a fourth axis center32brespectively located at two opposite ends thereof and passed through the center of spherical rotation C.

The third curved bar33has a fifth axis center33aand a sixth axis center33brespectively located at two opposite ends thereof and passed through the center of spherical rotation C. The third curved bar33is pivotally connected to the second curved bar32. Further, the fifth axis center33acoincides with the fourth axis center32b.

The fourth curved bar34has a seventh axis center34aand an eighth axis center34brespectively located at two opposite ends thereof and passed through the center of spherical rotation C. The fourth curved bar34is respectively pivotally connected to the third curved bar33and the first curved bar31. The seventh axis center34acoincides with the sixth axis center33b.The eighth axis center34bcoincides with the second axis center31b.

The ground bar35has a ninth axis center35aand a tenth axis center35brespectively located at two opposite ends thereof and passed through the center of spherical rotation C. Further, said ninth axis center35abeing coincided with said first axis center31a,and the tenth axis center35bcoincides with the third axis center32b.

The instrument bar36comprises an operational axis center36apassed through the center of spherical rotation C. The instrument bar36is pivotally connected to the third curved bar33or fourth curved bar34. Further, the operational axis center36acoincides with the sixth axis center33bor seventh axis center34a.

The first proportional wheel37is fixedly connected to the first curved bar31and rotatable with the first curved bar31to let the second axis center31bpass through the wheel axle center of the first proportional wheel37.

The diameter of the second proportional wheel38is larger than the diameter of the first proportional wheel37. Further, the second proportional wheel38is fixedly connected to the instrument bar36and rotatable with the instrument bar36to let the operational axis center36apass through the wheel axle center of the second proportional wheel38.

The flexible element39is wound round the first proportional wheel37and the second proportional wheel38. In this embodiment, the flexible element39is a steel wire rope. However, this is not a limitation. It can also be a rope or belt.

In this embodiment, in addition to the condition that the first curved bar31and the second curved bar32have the same length, the third curved bar33and the fourth curved bar34can also be made having the same length to simplify the calculation in controlling the motion of each curved bar. More particularly, the second curved bar32and the third curved bar33can be made having the same length. For example, in this embodiment, the first curved bar31, the second curved bar32, the third curved bar33and the fourth curved bar34have the same length, further reducing the calculation burden and shortening the calculation time. Further, due to the installation of the first proportional wheel37and the second proportional wheel38, there is a turn proportional relationship between the instrument bar36and the first curved bar37, and therefore the turning angle of the surgical instrument mounted at the instrument bar36can be reduced, bringing to the surgeon better readability of the data displayed on the surface of the surgical instrument when compared to conventional mechanical arm designs.