Abstract: A system and method for controlling avoiding collisions and deadlocks in a workcell containing multiple robots automatically determines the potential deadlock conditions and identifies a way to avoid these conditions. Deadlock conditions are eliminated by determining the deadlock-free motion statements prior to execution of the motions that have potential deadlock conditions. This determination of deadlock-free motion statements can be done offline, outside normal execution, or it can be done during normal production execution. If there is sufficient CPU processing time available, the determination during normal production execution provides the most flexibility to respond to dynamic conditions such as changes in I/O timing or the timing of external events or sequences. For minimal CPU impact the determination is done offline where many permutations of programming sequences can be analyzed and an optimized sequence of execution may be found.

Abstract: A robot multi-arm control system includes robot controllers that communicate via a network to transmit synchronization information from a master controller to one or more slave controllers in order to coordinate manufacturing processes. The system accounts for the network communication delay when synchronizing the event timing for process and motion synchronization.

Abstract: An apparatus and a method for optimizing robot performance includes a computer connected to the robot controller for receiving performance data of the robot as the controller executes a path program. The computer uses the performance data, user specified optimization objectives and constraints and a kinematic/dynamic simulator to generate a new set of control system parameters to replace the default set in the controller. The computer repeats the process until the new set of control system parameters is optimized.

Abstract: An apparatus and a method for optimizing robot performance includes a computer connected to the robot controller for receiving performance data of the robot as the controller executes a path program. The computer uses the performance data, user specified optimization objectives and constraints and a kinematic/dynamic simulator to generate a new set of control system parameters to replace the default set in the controller. The computer repeats the process until the new set of control system parameters is optimized.

Abstract: A system for performing the method of this invention includes a leader having a robot arm able to articulate about first axes and supporting an end effector. A follower includes a robot arm able to articulate about respective second axes. Servo motors articulate the leader arm about the first axes and the follower arm about the second axes. A user interface allows a user to jog the arm of the leader and to program movement of the arms for automatic execution such that the end effector reaches predetermined positions. A controller, operatively connected to the servo motors and the user interface, controls operation of the servo motors, moves the arm of the leader in accordance with the programmed movement, and moves the arm of the follower such that it tracks or mirrors movement of the leader.

Abstract: A robot multi-arm control system includes robot controllers that communicate via a network to transmit synchronization information from a master controller to one or more slave controllers in order to coordinate manufacturing processes. The system accounts for the network communication delay when synchronizing the event timing for process and motion synchronization.

Abstract: A method of controlling a robot (32) includes the steps of selecting an initial configuration from at least one of a first, second, and third sets to position a TCP at a starting point (44) along a path (33) and selecting a final configuration different than the initial configuration to position the TCP at an ending point (46). Next, the TCP moves from the starting point (44) while maintaining the initial configuration, approaches the singularity between a first point (48) and a second point (50), and selects one of the axes in response to reaching the first point (48). The angle for the selected axis is interpolated from the first point (48) to the second point (50). After the interpolation, the angles about the remaining axes are determined and positions the arms in the final configuration when the TCP reaches the second point (50) and moves to the ending point (46) while maintaining the final configuration.

Abstract: A system for performing the method of this invention includes a leader having a robot arm able to articulate about first axes and supporting an end effector. A follower includes a robot arm able to articulate about respective second axes. Servo motors articulate the leader arm about the first axes and the follower arm about the second axes. A user interface allows a user to jog the arm of the leader and to program movement of the arms for automatic execution such that the end effector reaches predetermined positions. A controller, operatively connected to the servo motors and the user interface, controls operation of the servo motors, moves the arm of the leader in accordance with the programmed movement, and moves the arm of the follower such that it tracks or mirrors movement of the leader.

Abstract: A method of controlling a robot (32) includes the steps of selecting an initial configuration from at least one of a first, second, and third sets to position a TCP at a starting point (44) along a path (33) and selecting a final configuration different than the initial configuration to position the TCP at an ending point (46). Next, the TCP moves from the starting point (44) while maintaining the initial configuration, approaches the singularity between a first point (48) and a second point (50), and selects one of the axes in response to reaching the first point (48). The angle for the selected axis is interpolated from the first point (48) to the second point (50). After the interpolation, the angles about the remaining axes are determined and positions the arms in the final configuration when the TCP reaches the second point (50) and moves to the ending point (46) while maintaining the final configuration.

Abstract: A method of teaching a robot a desired operating path and a lead-through teach handle assembly are disclosed. A mounting mechanism mounts the entire handle assembly to an arm of the robot. The handle assembly also includes a handle that is supported by the mounting mechanism. A robot operator utilizes the handle assembly and grasps the handle to apply an external force to move the robot arm, or the operator, without the handle assembly, directly holds a tool connected to the robot arm to apply the external force at the tool. The handle assembly is characterized by a universal joint that interconnects the handle and the mounting mechanism and that accommodates orientation changes of the handle relative to the mounting mechanism that result from translational and rotational movement of the robot arm as the user is teaching the robot. The external force applied at the tool is estimated with either a force sensor disposed on the handle assembly or by monitoring the torque of motors used to move the robot.

Abstract: A robot calibration system includes a calibration sensor that provides an indication of when a first reference point that remains fixed relative to a robot base is a fixed distance from a second reference point that is located on the robot arm. The robot arm is moved through a plurality of orientations and each time that the fixed distance between the two reference points is achieved, robot joint position information is determined. The preferred calibration sensor includes a string that extends between the two reference points and activates a signal generator each time that the string is taut as caused by the orientation of the robot arm. The generated signal indicates that the two reference points are separated by the fixed distance. The determined robot joint positions are then used to determine a calibration factor which varies depending on the needs of a particular situation.

Abstract: Method and system for trajectory or path planning to move a device such as a robot along a Cartesian path to achieve high path accuracy and ease of programming. Cascaded linear filters are utilized to perform acceleration/deceleration control in Cartesian space having six Cartesian components. Generally, six sets of such linear filters are used, three for location components and three for orientation components. Cartesian path blending is also provided. First and second path segments are planned and blended together and a corner distance is formed at a transition between the first and second path segments. A method is also provided for adjusting the corner distance. The corner distance is adjusted by corner distance variables which are independent of program speed so that the resultant Cartesian path can be maintained regardless of program speed changes.

Abstract: A method and device of achieving motion cycle time reduction that takes motor capabilities, load inertia and gravity into account and, at the same time, produces acceptable tool tip vibration upon stopping. This cycle time reduction is especially applicable to short motions of a robot where the entire motion consists of acceleration and deceleration and there is no constant velocity region. The method and device provide open loop limiting factors for axis jerk, acceleration and velocity, taking into account robot position, payload and inertia.