Robotic Manipulator with Remote Center of Motion and Compact Drive
A robotic manipulator device includes a robotic linkage to rotate an insertion axis about a remote center of motion with two degrees of freedom. A driven link supports the insertion axis. Rigid links in a parallelogram arrangement constrain the driven link to move in parallel to a drive link and the insertion axis to rotate about the remote center of motion. A drive unit has an output shaft coupled to the drive link. Rotation of an input shaft causes the output shaft to rotate. The input and output shafts are at a substantial angle. A housing supports the output shaft. A first motor causes the input shaft to rotate the output shaft. A second motor causes the housing to rotate, rotating the output shaft about an axis that is substantially parallel to the input shaft and passes through the remote center of motion.
1 . A robotic manipulator device comprising:
a robotic linkage having a drive link and a driven link that supports an insertion axis, the drive link and the driven link coupled by a plurality of rigid links in a parallelogram arrangement to constrain the driven link to constrain the insertion axis to rotate about a remote center of motion along the insertion axis;
a drive unit having an output shaft with a first axis of rotation coupled to the drive link, an input shaft with a second axis of rotation at a substantial angle to the first axis of rotation, rotation of the input shaft causing the output shaft to rotate, and a housing that supports the output shaft;
a first motor coupled to the input shaft of the drive unit to rotate the output shaft about the second axis of rotation; and
a second motor coupled to the housing of the drive unit to rotate the output shaft about a third axis of rotation that passes through the remote center of motion.
2 . The robotic manipulator device of claim 1 wherein the driven link supports the insertion axis at a fixed angle to a longitudinal axis joining pivot points of the driven link, the longitudinal axis intersecting the insertion axis at the remote center of motion.
3 . The robotic manipulator device of claim 1 wherein the third axis of rotation is collinear with the second axis of rotation.
4 . The robotic manipulator device of claim 1 wherein the second axis of rotation intersects the first axis of rotation at a right angle.
5 . The robotic manipulator device of claim 1 wherein the first motor is coupled to the housing of the drive unit.
6 . The robotic manipulator device of claim 1 wherein the first motor is coupled to the second motor.
7 . The robotic manipulator device of claim 1 wherein the output shaft is coupled to the drive link by a gear reducer.
8 . A robotic manipulator device comprising:
a robotic linkage having a drive link and a driven link that supports an insertion axis, the drive link and the driven link coupled by a plurality of rigid links in a parallelogram arrangement to constrain the insertion axis to rotate about a remote center of motion along the insertion axis;
a drive unit having an output shaft with a first axis of rotation coupled to the drive link, an input shaft with a second axis of rotation at a substantial angle to the first axis of rotation, rotation of the input shaft causing the output shaft to rotate, and a housing that supports the output shaft;
means for rotating the input shaft of the drive unit to rotate the output shaft about the second axis of rotation; and
means for rotating the housing of the drive unit to rotate the output shaft about a third axis of rotation that passes through the remote center of motion.
9 . The robotic manipulator device of claim 8 wherein the driven link supports the insertion axis at a fixed angle to a longitudinal axis joining pivot points of the driven link, the longitudinal axis intersecting the insertion axis at the remote center of motion.
10 . The robotic manipulator device of claim 8 wherein the third axis of rotation is collinear with the second axis of rotation.
11 . The robotic manipulator device of claim 8 wherein the second axis of rotation intersects the first axis of rotation at a right angle.
12 . The robotic manipulator device of claim 8 wherein the means for rotating the input shaft is coupled to the housing of the drive unit.
13 . The robotic manipulator device of claim 8 wherein the means for rotating the input shaft is coupled to the means for rotating the housing of the drive unit.
14 . The robotic manipulator device of claim 8 wherein the output shaft is coupled to the drive link by a gear reducer.
15 . A two-axis motor drive device comprising:
a drive unit having an output shaft with a first axis of rotation, an input shaft with a second axis of rotation at a substantial angle to the first axis of rotation, rotation of the input shaft causing the output shaft to rotate, and a housing that supports the output shaft;
a first motor coupled to the input shaft of the drive unit to rotate the output shaft about the second axis of rotation; and
a second motor coupled to the housing of the drive unit to rotate the output shaft about a third axis of rotation that passes through the remote center of motion.
16 . The two-axis motor drive device of claim 15 wherein the third axis of rotation is collinear with the second axis of rotation.
17 . The two-axis motor drive device of claim 15 wherein the second axis of rotation intersects the first axis of rotation at a right angle.
18 . The two-axis motor drive device of claim 15 wherein the first motor is coupled to the housing of the drive unit.
19 . The two-axis motor drive device of claim 15 wherein the first motor is coupled to the second motor.
20 . The two-axis motor drive device of claim 15 further comprising a gear reducer coupled to the output shaft.