Robotic arms with strap drive trains

摘要

In one embodiment of the invention, a robotic arm is provided including a linkage assembly and a strap drive train. The linkage assembly includes first, second, third, and fourth links pivotally coupled in series together at first, second, and third joints to define a parallelogram with an insertion axis. The strap drive train includes first and second sets of straps coupled to the linkage assembly. As the linkage assembly is moved about a pitch axis, the first set of straps ensures the third link maintains the same angle relative to the first link, and the first and second set of straps ensures the fourth link maintains the same angle relative to the second link.

主权项

1. A robotic arm comprising:
a linkage assembly including a plurality of links pivotally coupled in series together at one or more joints to slidingly support a tool along an insertion axis, the plurality of links including a first pulley and a second pulley; at least one strap coupled between the first pulley and the second pulley to drive the linkage assembly; and a strap tensioning system coupled to the at least one strap, the strap tensioning system to tension the at least one strap; wherein the strap tensioning system includes
the first pulley having a first pocket;the second pulley having a second pocket; andthe at least one strap including
a tab coupled to a first end of the at least one strap, the tab to hook into the first pocket of the first pulley to couple the first end of the at least one strap thereto, anda tensioning block coupled to a second end of the at least one strap, the tensioning block to hook into the second pocket of the second pulley to couple the second end of the at least one strap thereto;wherein the first pulley further has a first recess in a portion of its circumference joining the first pocket to receive the first end of the at least one strap, a first stop at a front of the first pocket to couple to a front side of the tab, a first side restraining protrusion extending from the first stop to retain the tab in the first pocket, and a first lip at the back of the first pocket to further retain the tab in the first pocket; andwherein the second pulley further has a second recess in a portion of its circumference joining the second pocket to receive the second end of the at least one strap, a second stop at a front of the second pocket to couple to a front side of the tensioning block, a second side restraining protrusion extending from the second stop to retain the tensioning block in the second pocket, and a second lip at the back of the second pocket to further retain the tensioning block in the second pocket.