Abstract: A robotic system includes a jointed mechanism, position sensors, and a controller. The mechanism has an end-effector, and further includes actively-controlled joints and passive joints that are redundant with the actively-controlled joints. The position sensors are operable for measuring joint positions of the passive joints. The controller is in communication with the position sensors, and is programmed to execute a method to selectively control the actively-controlled joints in response to the measured joint positions using force control and/or a modeled impedance of the robotic mechanism. Possible control modes in impedance control include an Autonomous Mode in which an operator does not physically interact with the end-effector and a Cooperative Control Mode in which the operator physically interacts with the end-effector.

Abstract: An extended-reach assist device for an assembly task includes a base mechanism and a compliant end-effector. The articulated base mechanism provides one or more passive degrees of freedom. The end-effector is connected to the base mechanism, and has one or more active or passive degrees of freedom collectively configured to react to contact forces with the assist device when completing the dexterous assembly task. A weight of the end-effector is supported by the base mechanism. The end-effector may be optionally configured as a passive device configured to produce a remote center of compliance or as a robot mechanism. A mechanism may actively or passively augment a force applied by the operator. A sensor may detect a signature indicative of successful task completion, e.g., an acoustic, visual, or audio sensor.

Abstract: A method for position correction of a machine relative to a work piece. The machine may be provided with an end effector. The work piece may be engaged with the end effector. A force or a moment resulting from engaging the work piece with the end effector may be measured. A pose error may be determined from the force and/or the moment, wherein the pose error may define a misalignment of the end effector. The end effector may be repositioned an amount equal to the pose error to correct the misalignment. One application may involve torqueing nuts with a nut runner, which may be accomplished through the use of an automated machine such as a robot.

Abstract: A method for position correction of a machine relative to a work piece. The machine may be provided with an end effector. The work piece may be engaged with the end effector. A force or a moment resulting from engaging the work piece with the end effector may be measured. A pose error may be determined from the force and/or the moment, wherein the pose error may define a misalignment of the end effector. The end effector may be repositioned an amount equal to the pose error to correct the misalignment. One application may involve torqueing nuts with a nut runner, which may be accomplished through the use of an automated machine such as a robot.

Abstract: A robotic system includes a jointed mechanism, position sensors, and a controller. The mechanism has an end-effector, and further includes actively-controlled joints and passive joints that are redundant with the actively-controlled joints. The position sensors are operable for measuring joint positions of the passive joints. The controller is in communication with the position sensors, and is programmed to execute a method to selectively control the actively-controlled joints in response to the measured joint positions using force control and/or a modeled impedance of the robotic mechanism. Possible control modes in impedance control include an Autonomous Mode in which an operator does not physically interact with the end-effector and a Cooperative Control Mode in which the operator physically interacts with the end-effector.

Abstract: An electromechanical system operates through physical interaction with an operator, and includes a plurality of joints providing multiple degrees of freedom (DOF), including actuated joints and unactuated joints. The unactuated joints are distal with respect to the actuated joints and are in redundant DOF to the actuated joints. The system includes a plurality of actuators each configured to actuate one or more of the actuated joints, and a plurality of sensors each positioned with respect to a respective one of the actuated and unactuated joints. Each sensor is configured to measure corresponding joint data indicative of a position or angle of the respective actuated or unactuated joints. A controller in communication with the sensors receives the measured joint data as feedback signals, generates control signals using the feedback signals, and transmits the control signals to the actuators to thereby control an actuation state of the actuators.

Abstract: A system for demonstrating a task to a robot includes a glove, sensors, and a controller. The sensors measure task characteristics while a human operator wears the glove and demonstrates the task. The task characteristics include a pose, joint angle configuration, and distributed force of the glove. The controller receives the task characteristics and uses machine learning logic to learn and record the demonstrated task as a task application file. The controller transmits control signals to the robot to cause the robot to automatically perform the demonstrated task. A method includes measuring the task characteristics using the glove, transmitting the task characteristics to the controller, processing the task characteristics using the machine learning logic, generating the control signals, and transmitting the control signals to the robot to cause the robot to automatically execute the task.

Abstract: An articulated compliance mechanism for use with a support structure includes a carriage and a pair of parallel four-bar linkage arrangements. The arrangements collectively have a first set of links configured to rigidly connect to the support structure, a second set of links rotatably coupled to the carriage a distance from the first set of links, and a third set of links rotatably coupled to and spanning the distance. The compliance mechanism supports and provides the carriage, e.g., a rectangular shaped frame, with a stable equilibrium point using a gravitational restoring force, and provides the carriage with a passive translational degree of freedom along a horizontal axis in response to an input force from an operator. An additional compliance mechanism may be serially connected to provide a passive translational degree of freedom along a vertical axis. A system includes the compliance mechanism and support structure.

Abstract: An extended-reach assist device for an assembly task includes a base mechanism and a compliant end-effector. The articulated base mechanism provides one or more passive degrees of freedom. The end-effector is connected to the base mechanism, and has one or more active or passive degrees of freedom collectively configured to react to contact forces with the assist device when completing the dexterous assembly task. A weight of the end-effector is supported by the base mechanism. The end-effector may be optionally configured as a passive device configured to produce a remote center of compliance or as a robot mechanism. A mechanism may actively or passively augment a force applied by the operator. A sensor may detect a signature indicative of successful task completion, e.g., an acoustic, visual, or audio sensor.

Abstract: A system and method for automating an assembly process of threading a tube-nut onto a threaded connector. The system includes a robot having a force sensor and a tube-nut runner tool coupled to the robot and having a tool head with a rotatable socket therein. The method includes engaging the socket to the tube-nut under force control using the force signal from the force sensor. The tool controller causes the socket to rotate the tube-nut where the tool controller controls the torque and/or angle displacement of the tool head to tighten the tube-nut on the threaded connector. The method also includes disengaging the tool head from the tube-nut after the tube-nut is properly tightened onto the threaded connector under force control to ensure that the end member is properly disengaged from the tube-nut.

Abstract: A method for position correction of a machine relative to a work piece. The machine may be provided with an end effector. The work piece may be engaged with the end effector. A force or a moment resulting from engaging the work piece with the end effector may be measured. A pose error may be determined from the force and/or the moment, wherein the pose error may define a misalignment of the end effector. The end effector may be repositioned an amount equal to the pose error to correct the misalignment. One application may involve torqueing nuts with a nut runner, which may be accomplished through the use of an automated machine such as a robot.

Abstract: A system for assisting an operator in a manual assembly task includes a base assembly, end-effector, and controller. The base assembly has joint actuators providing three or more degrees of freedom (DOF). The end-effector is in series with the base assembly and has additional joints providing one or more additional DOFs. The base assembly and end-effector support a task load, including a weight and/or a reaction torque of an object. Sensors measure joint positions. The controller receives the measured positions, controls the joint actuators to support the task load, and extends a range of motion of the object. A method includes receiving the position signals as the operator manipulates the object, generating an output signal using the measured positions, and transmitting the output signal to the joint actuators to control the joint actuators, support the task load, and extending a range of motion of the object.

Abstract: A system for assembling a first component and a second component comprises a support operatively supporting the first component without any fixtures, a vision system configured to view the supported first component and the second component and determine the locations thereof, a robotic system configured to move and position the second component relative to the first component, and a controller operatively connected to the vision system and to the robotic system and operable to control the robotic system to position the second component relative to the first component based on the locations determined by the vision system. Various methods of assembling the first component and the second component are provided to create a process joint prior to creation of a structural joint in a subsequent assembly operation.

Abstract: A system and method for automating an assembly process of threading a tube-nut onto a threaded connector. The system includes a robot having a force sensor and a tube-nut runner tool coupled to the robot and having a tool head with a rotatable socket therein. The method includes engaging the socket to the tube-nut under force control using the force signal from the force sensor. The tool controller causes the socket to rotate the tube-nut where the tool controller controls the torque and/or angle displacement of the tool head to tighten the tube-nut on the threaded connector. The method also includes disengaging the tool head from the tube-nut after the tube-nut is properly tightened onto the threaded connector under force control to ensure that the end member is properly disengaged from the tube-nut.

Abstract: A color recognition method includes determining a predefined set of colors within a color space and storing the predefined set of colors in a memory; determining a desired color selected from the predefined set of colors; receiving an image; filtering the image with a processor to produce a filtered image substantially comprising only the predefined set of colors; and determining whether the desired color is present within the image.

Abstract: A robotic system includes a robotic mechanism responsive to velocity control signals, and a permissible workspace defined by a convex-polygon boundary. A host machine determines a position of a reference point on the mechanism with respect to the boundary, and includes an algorithm for enforcing the boundary by automatically shaping the velocity control signals as a function of the position, thereby providing smooth and unperturbed operation of the mechanism along the edges and corners of the boundary. The algorithm is suited for application with higher speeds and/or external forces. A host machine includes an algorithm for enforcing the boundary by shaping the velocity control signals as a function of the reference point position, and a hardware module for executing the algorithm. A method for enforcing the convex-polygon boundary is also provided that shapes a velocity control signal via a host machine as a function of the reference point position.

Abstract: A robotic system includes a robot having a total number of degrees of freedom (DOF) equal to at least n, an underactuated tendon-driven finger driven by n tendons and n DOF, the finger having at least two joints, being characterized by an asymmetrical joint radius in one embodiment. A controller is in communication with the robot, and controls actuation of the tendon-driven finger using force control. Operating the finger with force control on the tendons, rather than position control, eliminates the unconstrained slack-space that would have otherwise existed. The controller may utilize the asymmetrical joint radii to independently command joint torques. A method of controlling the finger includes commanding either independent or parameterized joint torques to the controller to actuate the fingers via force control on the tendons.

Abstract: An SEA architecture for controlling the torque applied by an SEA that has particular application for controlling the position of a robot link. The SEA architecture includes a motor coupled to one end of an elastic spring and a load coupled to an opposite end of the elastic spring, where the motor drives the load through the spring. The orientation of the shaft of the motor and the load are measured by position sensors. Position signals from the position sensors are sent to an embedded processor that determines the orientation of the load relative to the motor shaft to determine the torque on the spring. The embedded processor receives reference torque signals from a remote controller, and the embedded processor operates a high-speed servo loop about the desired joint torque. The remote controller determines the desired joint torque based on higher order objectives by their impedance or positioning objectives.

Abstract: A humanoid robot includes a torso, a pair of arms, two hands, a neck, and a head. The torso extends along a primary axis and presents a pair of shoulders. The pair of arms movably extend from a respective one of the pair of shoulders. Each of the arms has a plurality of arm joints. The neck movably extends from the torso along the primary axis. The neck has at least one neck joint. The head movably extends from the neck along the primary axis. The head has at least one head joint. The shoulders are canted toward one another at a shrug angle that is defined between each of the shoulders such that a workspace is defined between the shoulders.

Abstract: A robotic system includes a tendon-driven finger and a control system. The system controls the finger via a force-based control law when a tension sensor is available, and via a position-based control law when a sensor is not available. Multiple tendons may each have a corresponding sensor. The system selectively injects a compliance value into the position-based control law when only some sensors are available. A control system includes a host machine and a non-transitory computer-readable medium having a control process, which is executed by the host machine to control the finger via the force- or position-based control law. A method for controlling the finger includes determining the availability of a tension sensor(s), and selectively controlling the finger, using the control system, via the force or position-based control law. The position control law allows the control system to resist disturbances while nominally maintaining the initial state of internal tendon tensions.