A position/force controller performs a first conversion for distributing control energy to at least one of velocity or position energy and force energy, in accordance with a function to be realized, based on velocity (or position) and force information, which correspond to information relating to a position based on an operation of an actuator, and information serving as reference of control. The position/force controller calculates at least one of a velocity or position control amount and a force control amount based on at least one of the energies obtained through the distribution. The position/force controller integrates the calculated control amounts, performs a second conversion, and determines input to the actuator. The position/force controller performs a process, corresponding to increasing or decreasing performed on at least one of the velocity or position energy and the force energy together or independently, with satisfaction of a condition set for the control energy.

A robot collision avoidance motion optimization technique using a distance field constraint function. CAD or sensor data depicting obstacles in a robot workspace are converted to voxels, and a three-dimensional binary matrix of voxel occupancy is created. A corresponding distance map matrix is then computed, where each cell in the distance map matrix contains a distance to a nearest occupied cell. The distance map matrix is used as a constraint function in a motion planning optimization problem, where the optimization problem is convexified and then iteratively solved to yield a robot motion profile which avoids the obstacles and minimizes an objective function such as distance traveled. The distance field optimization technique is quickly computed and has a computation time which is independent of the number of obstacles. The disclosed optimization technique is easy to set up, as it requires no creation of geometry primitives to approximate robot and obstacle shapes.

A motion planning method for robot arms includes: calculating an arm angle range of each pose of a tail end of a robot arm in the motion trajectory; calculating a start arm angle value of a start pose of the tail end of the robot arm in the motion trajectory; calculating an arm angle proportion according to the start arm angle value and the arm angle range of the start pose; identifying an abruptly changing arm angle range in the arm angle range of each pose according to a upper boundary curve and a lower boundary curve; calculating an arm angle of a pose corresponding to the abruptly changing arm angle range; calculating arm angles corresponding to the other poses according to the arm angle proportion; and calculating an angle of a joint of the robot arm.

A robotic system for use with a payload includes a robot, a passive compliance mechanism, position sensors, and an electronic control unit (ECU). Actuated joints of the robot provide the robotic system with actuated degrees of freedom (DOF). The compliance mechanism is connected to the robot and payload, and has unactuated joints providing the robotic system with unactuated DOF. The sensors measure joint positions of the joints. The ECU has a trajectory generator block which generates a payload trajectory signal in response to dynamic control inputs, and an impedance control unit (ICU) applying damping and stiffness parameters to the payload trajectory signal to generate an initial velocity command. A stiction compensation block allows the robotic system to generate a velocity offset, and applies the velocity offset to the initial velocity command to produce a final velocity command for the robot.

A method for controlling movement of a robot having a plurality of links connected by rotatably driven joints includes the steps of: a) defining a target speed vector of a reference point of the robot in Cartesian space; b) determining rotation speeds ({dot over (q)}.sub.ref) of the joints which minimize a weighted sum, the weighted sum having for summands i) a discrepancy (∥{dot over (x)}.sub.ref.sup.k−J{dot over (q)}.sub.ref.sup.k∥.sub.W.sub.x) between the target speed vector ({dot over (x)}.sub.ref) and an actual speed vector ({dot over (x)}.sub.act) calculated from actual rotation speeds of the joints; and ii) a rate of change $\left(\frac{1}{T_S}{.Math.{\stackrel{.}{q}}_{\mathrm{ref}}^k-{\stackrel{.}{q}}_{\mathrm{ref}}^{k-1}.Math.}_{W_a}\right)$
of the target rotation speeds; and c) setting the rotation speeds ({dot over (q)}.sub.ref) determined in step (b) as target rotation speeds of the joints.

A control device for a robot is configured to control operation of a robotic arm having a plurality of links coupled to each other through a rotation axis, and a motor for drive provided to the rotation axis. The control device includes an angle calculating module configured to calculate an angle formed by the two links adjacent to each other through the rotation axis, and an angle monitoring module configured to monitor whether the angle calculated by the angle calculating module is a given angle or below.

Methods, apparatuses, systems, and computer program products for an improved anti-sway control system and adjustable end effector for a robotic arm are provided. An example method includes determining at least one of a size, shape or orientation of a package to be picked up by an end effector of a robotic arm and facilitating adjusting a position of a suction cup on the end effector, wherein the position is determined based on the at least one determined size, shape, or orientation of the package. The method further includes facilitating grasping the package with the end effector and facilitating movement of the end effector via a robotic joint to reduce force on the suction cup by the package due to an acceleration of the package due to movement of the robotic arm.

A method and system for motion planning for robots with a redundant degree of freedom. The technique computes a collision avoidance motion plan for a robot with a redundant degree of freedom, without artificially constraining the extra degree of freedom. The motion planning is formulated as a quadratic programming optimization calculation having a multi-component objective function and a collision avoidance constraint function. The formulation is efficient enough to compute the motion plan in real time at every robot control cycle. The collision avoidance constraint ensures clearance of all parts of the robot from both static and dynamic obstacles. Objective function terms include minimizing path deviation, joint velocity regularization and robot configuration or pose regularization. Weighting factors on the terms of the objective function are changeable for each control cycle calculation based on obstacle proximity conditions at the time.

A control device for controlling a machine with axes having a corotational relation includes: axis position detectors; motor position detectors; a position command calculation unit calculating a position command for each of the axes based on an operation program; a position control unit outputting a speed command of each motor based on the position command and the detection position of the corresponding axis; a speed control unit controlling each motor based on the speed command; and a correction value calculation unit calculating a correction value for correcting, based on the corotational relation, the speed command of a motor with a to-be-controlled axis which is an axis rotating dependent on the corotational relation. The speed control unit corresponding to the to-be-controlled axis corrects the speed command based on the correction value so as to be applied to control of the motor with the to-be-controlled axis.

An abnormality detection method for detecting an abnormality of an encoder provided for a robot includes: obtaining corrected position information according to commanded position information output from a controller that designates the rotational position of a motor and an output signal output from the encoder; and, determining, after comparing the corrected position information with the detected position information according to the output signal output from the encoder, the abnormality of the encoder, if there is a difference greater than or equal to a predetermined value between the corrected position information and the detected position information. The controller removes a vibration component of the robot corresponding to the weight of an attachment load from the commanded position information and compensates for a time delay to obtain the corrected position information.