A robot system includes a work bench on which a work piece is placed, and a robot device. The robot device includes: a base; and an arm section that has torsional rotatability around a first axis approximately along a center line of the base, bending rotatability around a second axis that is orthogonal to the first axis, and linear extensibility and retractability along a third axis that is orthogonal to the second axis. Work is performed in collaboration with a worker on the work piece by means of an end effector that is mounted at a tip of the arm section. The base is disposed so that a moveable region of the arm section accompanying rotation around the first axis and the second axis and linear extension and retraction along the third axis overlaps with a working region of the worker.

A rigidity of a robot arm mechanism including a linear extension and retraction joint is enhanced. In a robot arm mechanism including the linear extension and retraction joint, the linear extension and retraction joint includes an arm section and an ejection section, the arm section includes a first connection piece string including a plurality of first connection pieces and a second connection piece string including a plurality of second connection pieces, and the second connection piece string is joined to the first connection piece string to thereby constitute a columnar body having a certain rigidity. The ejection section includes lower rollers and upper rollers for joining the first and second connection piece strings and supporting the columnar body. The lower rollers and the upper rollers are disposed with the columnar body sandwiched between the lower rollers and the upper rollers.

The disclosed embodiments relate to systems and methods for a surgical tool or a surgical robotic system. One example method includes providing a redundant degree of freedom (DoF) for an end effector joint of one DoF by driving the joint with two actuators, calculating a position displacement of the joint to effect a desired end effector movement in response to an input command, calculating a first movement of the two actuators based on the position displacement of the joint and a second movement of the two actuators based on a second control objective in a null space corresponding to the redundant DoF, and driving the joint according to the first movement and the second movement to effect the desired end effector movement while accomplishing the second control objective in the null space.

A method is provided for constructing a robotic arm including a plurality of links and a rope assembly. The method includes providing the rope assembly having a rope with a plurality of rope bearings threaded thereon; and attaching the plurality of rope bearings of the rope assembly to the plurality of links of the robotic arm.

A method is provided for constructing a robotic arm including a plurality of links and a rope assembly. The method includes providing the rope assembly having a rope with a plurality of rope bearings threaded thereon; and attaching the plurality of rope bearings of the rope assembly to the plurality of links of the robotic arm.

The disclosed embodiments relate to systems and methods for a surgical tool or a surgical robotic system. One example method includes providing a redundant degree of freedom (DoF) for an end effector joint of one DoF by driving the joint with two actuators, calculating a position displacement of the joint to effect a desired end effector movement in response to an input command, calculating a first movement of the two actuators based on the position displacement of the joint and a second movement of the two actuators based on a second control objective in a null space corresponding to the redundant DoF, and driving the joint according to the first movement and the second movement to effect the desired end effector movement while accomplishing the second control objective in the null space.

An apparatus including computer program code configured to cause the apparatus to: receive a command defining a desired pose of an end effector of a robotic instrument; determine, based on the command, joint parameters for each joint of the robotic instrument using an inverse kinematics algorithm to enable the end effector to mimic the desired pose as closely as possible, wherein the algorithm is configured to reiteratively calculate a pose of the end effector and identify the calculated pose with the smallest tracking error as a global solution if the tracking error is smaller than that associated with a current pose of the end effector, otherwise identify the current pose as the global solution; and wherein the apparatus is configured to generate a motor command to reconfigure the joints according to the global solution if the calculated pose with the smallest tracking error is identified as the global solution.