Abstract: The system includes a sensor for detecting a state of a space; a robot for executing a handling job for an article; an article identifying part for identifying, when an article is handled by a movable body, the article in response to a detection result obtained by the sensor; and an article handling subject identifying part for identifying an article handling subject that handles the article. When the movable body that handles the article is the robot, the article handling subject identifying part identifies a subject having issued a job instruction to the robot as the article handling subject.

Abstract: A method for controlling a painting system including an industrial robot or manipulator arm arranged with a wrist section and carrying a paint applicator arranged on the robot wrist is described. Paint is applied by the applicator to a substantially circular or elliptical area on the surface, the center of the area being defined as a Tool Center Point. The wrist section is arranged capable of moving and orienting the paint applicator. In the method, the paint applicator is moved by the manipulator arm so that the Tool Center Point moves along a planned path so coating a part of the surface. The planned path may include one or more bends. The path taken by the robot wrist may be controlled to follow a different path from the path taken by the Tool Center Point. A system and a computer program for carrying out the method are also described.

Abstract: In an autonomous vehicle, position of a planar obstacle such as a wall or a fence having apertures is determined. A horizontal plane is scanned with a laser range tinder so as to acquire positional coordinates of a plurality of scanning points. An element vector is formed with each two scanning points so that one acquired former is used as a start point and the other acquired later as an end point of the vector. A plurality of continuous element vectors which satisfy predetermined conditions is selected among the element vectors, and a scanning segment vector is formed by composition of the selected element vectors. When a length of the scanning segment vector is equal to or longer than a predetermined length, it is possible to recognize that a planar obstacle exists along the scanning segment vector.

Abstract: A docking system includes: a station including: a light emitter comprising light emitting elements arranged in a circular arc form so as to cause optical axes of light generated from the light emitting elements to pass through a curvature center of the circular arc; and a self-moving robot including: a body part having a circular arc part being substantially the same in curvature radius as the circular arc of the station; a movement mechanism attached to the body part to move the body part and capable of causing the body part to conduct on-the-spot rotation at a curvature center of the circular arc part; light receivers attached to the body part to receive a light signal from the light emitter; a direction detector detecting a direction in which the light signal is emitted; and a controller controlling the movement mechanism to move the body part in the direction detected by the direction detector.

Abstract: The invention relates to a method for the targeted reaction in the event of contact between an element (4, 6) pertaining to a machine and an object (5, 7), and a corresponding control device (14). Upon identification of contact between the machine element (4, 6) and the object (5, 7), if the machine axle is shifted into rapid displacement mode in an automated manner during the contact by means of a control device (14), further displacement of the machine axle (3, 41, 42, 43) is stopped by the drive (42, 43) of the machine (3, 41, 42, 43) being immediately cut off. Upon identification of contact, if the machine axle is shifted into slow displacement mode in an automated manner during the contact by means of a control device (14), collision detection is carried out, further displacement of the machine axle (3, 41, 42, 43) being stopped if a collision is detected.

Abstract: A safety condition setting support device is used for a safety network to which an input device and an output device are connected and the output device serves to stop a controlled apparatus based on a detection signal outputted from the input device when the input device has detected a danger condition. The support device serves to set safety conditions for stopping the controlled apparatus within a specified time period and includes an apparatus data memory for storing data related to internal processing times of safety devices connected to the safety network including the input and output devices, data obtaining device obtaining connection data showing connection relationship among the safety devices and transmission intervals among the safety devices or a safety distance between the input device and the controlled apparatus, and a calculating device for obtaining the safety conditions based on these obtained data.

Abstract: A robot control apparatus allows a plurality of mobile robots to carry out tasks at a reduced or minimized cost as a whole with consideration given to costs derived from an encounter with an obstacle is provided. An action optimization controller provided in the robot control apparatus generates an instruction for optimizing actions of the plurality of mobile robots so that the plurality of mobile robots carry out the tasks at a minimized cost, based upon locomotion plan information indicative of locomotion plans of the plurality of mobile robots. A possibility that any robots have an encounter with an obstacle is determined by comparing distances from the robots to the obstacles. A locomotion plan implementation cost is calculated with consideration given to the possibility of encounter, and thus an optimum route is selected based upon the locomotion plan implementation cost with the encounter-derived cost. In accordance with the optimum route, the locomotion plan for the robot is modified.

Abstract: A method of moving a virtual articulated object in a succession of individual movements in a virtual environment, the articulated object being specified in the environment by a global position, a global orientation, and a plurality of joint angles defining the positions of a set of articulated elements making up the articulated object with a plurality of degrees of freedom. The method includes the steps of calculating an interaction distance between the articulated object and its environment; extracting from the interaction distance a first point belonging to one of the elements of the articulated object, and a second point belonging to the environment; and defining a single extraction vector from the first and second points.

Abstract: A synchronous high speed motion stop for a series of multi-top loaders residing on “n” controllers on one rail achieves effective detection of the servo-error status and shut off of the trailing controller's servo power within 3 ITP time. The control method reduces the unnecessary error recovery because it only shuts off its immediate trailing controller without aborting its leading controller, allowing the leading controller to complete the cycle tasks. The cascade control method produces a synchronous high-speed motion stop for the robots across the controllers and effectively prevents the collision between the robots.

Abstract: A system and method for monitoring a lifting device is disclosed. The method receives location information from a position determiner module coupled with a point of interest associated with the lifting device and determines an autonomous position of the point of interest based on the location information. The method further includes monitoring the lifting device based on the autonomous position of the point of interest.

Abstract: An industrial robot system including a plurality of industrial robots. Each robot includes a manipulator, a control unit for automatically operating the manipulator, and a movable key device configured to store information about the identity of the robot to which the moveable key device belongs. A portable operating unit is configured to teach and program the robots. The portable operating unit is adapted for wireless communication with each control unit. The portable operating unit includes a member for receiving one of the moveable key devices, a reader for reading a robot identity from the received moveable device, and a communication establisher for establishing wireless communication between the operating unit and the control unit of the identified robot upon reading the robot identity from the moveable key device.

Abstract: An obstacle detection apparatus and method which can detect the state of an obstacle according to a signal generated when the obstacle detection apparatus collides with the obstacle and a change in the posture of the obstacle detection apparatus caused due to the collision with the obstacle. The obstacle detection apparatus includes a main body which can be moved along the surface of the ground, a movement amount determination module which determines whether the amount of movement of the main body is outside a predefined threshold range, a posture determination module which determines the changed posture of the main body with respect to the surface of the ground according to the amount of movement of the main body, and a state determination module which determines the state of an obstacle based on the results of determination of the movement amount determination module or the posture determination module.

Abstract: A method for calibrating a controller of a robotic arm in a microelectronics manufacturing apparatus that includes storing a default position for an edge detector, moving a blade on the robotic arm based on the default position of the edge detector such that at least three edge points on the blade pass through and are detected by the edge detector, generating a plurality of arm position measurements from an arm position sensor by measuring a position with the arm position sensor of the robotic arm at each position of the robotic arm at which an edge point of the blade is detected by the edge detector, and determining at least one of an actual position of the edge detector and an offset for measurements of the arm position sensor based on the plurality of arm position measurements.

Abstract: A robot is provided with a motion control unit that avoids collision between segments of the robot or between segments of the robot and other objects. The motion control unit of the robot comprises a distance computing module, a whole body control module, a collision avoidance module, and a blending control unit. The distance computing module calculates two closest points of different segments of the robot connected to each other via at least one joint or a segment of the robot and another object. The collision avoidance module is provided with the information about the two closest points. The blending control unit combines the weighted output control signals of the whole body control module and the collision avoidance control module. The weight of the whole body control output signal is higher when the risk of collision is lower. The weight of the collision avoidance control output signal is higher when the risk of collision is higher.

Abstract: A robot system efficiently performing an operation of moving a robot to close to and/or separate from a target point, such as teaching operation. A camera of a visual sensor is mounted to the robot such that a distal end of an end effector is seen within the field of view of the camera, and the end effector's distal end and a target position on an object are specified on a monitor screen. When an approach key is depressed, a target position is detected on an image, and a difference from a position of the end effector's distal end is calculated. Whether the difference is within an allowable range is checked. Depending on the result, an amount of robot motion is calculated, and the robot is operated. The processing is repeated until the depressed approach key is released. When a retreat key is depressed, the robot moves away from the object. The robot may be caused to stop using a distance sensor.

Abstract: A method for controlling a robot during an interpolation of a trajectory or motion to any prescribed position, comprises the steps of a) ignoring at least one of the three originally prescribed or interpolated tool center point orientation values; b) finding new tool center point orientation values that place the wrist center point of the robot closest to its base while c) maintaining the originally prescribed or interpolated tool center point location values and d) maintaining the original prescribed or interpolated tool center point orientation values not ignored. Said method can preferably be used for carrying a load with a plurality of robots. Its main advantage is an increase of the available working volume.

Abstract: A method of moving a virtual articulated object in a virtual environment in a succession of unit movements, the articulated object including a set of articulated elements connected together by a set of joints, the relative positions of the articulated elements being defined by a plurality of joint angles about a plurality of degrees of freedom. The method includes the steps of calculating an interaction distance between a given articulated element and the other articulated elements of the articulated object; extracting from the interaction distance, a first point belonging to the given articulated element, and a second point belonging to one of the other articulated elements of the articulated object; and defining a single extraction vector from the first and second points.

Abstract: In a biped robot control system, stereoscopic images captured by CCD cameras are analyzed, the analyzed images are then utilized to detect presence of any moving object around the robot and if it present, to calculate moving object information, and based on the calculated moving object information, it is determined whether or not walking of the robot needs to be stopped. If it is determined to be stopped, the robot is controlled to stop within a period that brings the travel distance at stopping (distance moved between image capture by the CCD cameras and stopping of robot walking) to within a predetermined distance. With this, when the robot approaches a moving object during walking, it can be stopped within the predetermined distance to avoid collision with the moving object.

Abstract: A robot device includes a sensor on its base plate capable of sensing rotation of the base plate occasioned by decoupling of a detachable joint that joins a forearm member of the robot to the base plate. The sensor produces an output signal which, if above a preset threshold, shuts off the motors driving the robot.

Abstract: There is provided a robot apparatus which can improve work safety while ensuring high working efficiency and a control method for the robot apparatus. The robot apparatus includes a moving body detection unit which generates a predicted moving range for a movable unit region by predicting a range within which the movable unit region moves using a plurality of images sequentially sensed by an image sensing unit and attempts to detect a moving body in the predicted moving range and a control unit which, if a moving body is detected by the moving body direction unit, changes the operation of a movable unit.

Abstract: A modular robot development kit includes an extensible mobile robot platform and a programmable development module that connects to the mobile robot platform. The mobile robot platform includes a controller that executes robot behaviors concurrently and performs robot actions in accordance with robot control signals received from the development module, as modified by the concurrently running robot behaviors, as a safeguard against performing potentially damaging robot actions. Also, the user can develop software that is executed on the development module and which transmits the robot control signals to the mobile robot platform over the data communication link using a robot interface protocol.

Abstract: Provided are a management ship and working robots in waters based on a wireless network and a method for controlling working robots thereof. The robot-ship group includes: a signal strength measuring unit for measuring strengths of pre-defined signals; and a working robot control unit for determining which of the first mother ship and the second mother ship the working robot is to communicate with according to a comparison result of the signal strength, and controlling the working robots to perform the work according to a set-up route, wherein the first mother ship includes: a working robot preparing unit for performing a preparation work required before and after the working robots perform the work; and a mother ship control unit for transmitting the pre-defined signal to the working robot and communicating data with the working robot.

Abstract: A robotic system for systematically moving about an area to be covered. The system includes at least one boundary marker (48) located along the outer edge of the area to be covered, a robot (40) with a navigation system (41) that navigates the robot (40) in generally straight, parallel lines from an initial location and turns the robot (40) when the robot (40) encounters one of the boundary markers (48), thereby to systematically move about the area to be covered. The sensor unit (43) senses proximity to one of the at least one boundary marker (48).

Abstract: A legged mobile robot, a legged mobile robot controller and a legged mobile robot control method are provided to perform a loading operation to load a gripped object in parallel on a target place having a height where a stretchable range of arm portions of the legged mobile robot is enhanced with no operator's handling. The legged mobile robot includes the arm portions having links for gripping an object, and leg portions having links for moving, and the arm and the leg portions are joined to a body thereof. The legged mobile robot controller includes a data acquisition unit, a whole-body cooperative motion control unit and a loading detection unit, and controls motions of the legged mobile robot based on posture/position data regarding a posture/position of each link of the legged mobile robot and on an external force data regarding an external force affecting the arm portions.

Abstract: An operation control unit of a reception system includes a visitor ID information DB for storing therein visitor comparison information and visitor ID information including a phone number of a receiver of a visitor; an identifying unit for identifying the visitor when visitor information obtained by a camera or the like of the robot is identical to the visitor comparison information; a phone calling module for calling the phone number of a mobile terminal of the receiver via a phone network, when the visitor is identified; an informing content determining unit for determining an informing content to the receiver based on the visitor ID information, when the visitor is identified; and a speech generating part for converting the received information into a voice. The informing content is sent to the mobile terminal of the receiver via the phone network.

Abstract: Controlling an orienting/positioning system having a sensor and actuator for controlling at least one of an orienting and positioning action of the sensor. The invention (1) evaluates pre-action output information of a sensor in order to detect the position of a pattern in the input space of the sensor, (2) determines a targeted post-action position of the pattern in the input space of the sensor, (3) defines an actuator command by mapping any deviation of the pre-action and post action position in the input space to actuator control coordinates using a predefined mapping function, (4) controls the actuators according to the defined command to execute the orienting/positioning action, (5) detects the real post-action position of the pattern in an input space of the sensor, (6) adapts the mapping function based on differences between the real post-action position and the targeted post-action position of the pattern in the input space.

Abstract: A cleaning robot and a control method thereof in which a cleaning path desired by the user is recognizable by the cleaning robot, thereby being capable of cleaning a cleaning area desired by the user in a pattern desired by the user. The cleaning robot includes a running unit to run the cleaning robot, a storage unit for storing a running path, along which the cleaning robot has learned, and a control unit to recognize the learned running path of the cleaning robot when a path learning operation is required, to store the recognized learned running path in the storage unit, and to drive the running unit. When a cleaning operation of the cleaning robot along the stored learned running path is required, the control unit controls the running unit to cause the cleaning robot to perform the required cleaning operation while running along the stored learned running path.

Abstract: When braking of a motion of a part of a first robot is assumed to be started at points in time, a first stop position of the first robot part is estimated at each point in time. When braking of a motion of a part of a second robot is assumed to be started at the points in time, an estimated second stop position of the second robot part is obtained at each point in time. When it is determined that the first stop position of the first robot part at one of the points in time and either the actual position or the second stop position of the second robot part for each interval at the one of the points in time are contained in the shared workspace, the first robot part is braked.

Abstract: A method for picking up objects randomly arranged in a bin using a robot having a gripper for grasping the objects using prehension feature(s) on the object. The method includes a shaking scheme for rearranging the objects in the bin when no objects are recognized, when no objects are prehensible by the gripper or when the object to be picked up is not reachable by the gripper because, for example, its prehension feature is substantially facing a wall of the bin. The method also includes a criterion for determining that a bin is free of objects to be picked up and a criterion for selecting the object to be picked up first in the bin. The method also provides for a protection mechanism against damage of the objects and the robot when a recognition technique has failed in properly recognizing the object or the prehension feature on the object.

Abstract: In a method for controlling the movement of a manipulator associated with an interpretation of a given point sequence of poses (positions and orientations) by splines, the motion components are separately parameterized. Thus, marked, subsequent changes to the orientation of robot axes have no undesired effects on the Cartesian movement path of the robot. Suitable algorithms are provided for orientation control by using quaternions or Euler angles.

Abstract: In the articulated robot, types of teaching a moving track of the robot can be optionally selected. The articulated robot comprises: a switch for manually selecting a moving axis to move an arm section along the selected axis; a manual pulse generator generating pulses; first controller for controlling motors to linearly move a front end of the arm section a prescribed distance, which corresponds to number of pulses; an operating board including a selecting switch, which is used to move the arm section along the selected axis; second controller for automatically controlling the motors so as to move the arm section while the selecting switch is turned on; third controller for stopping the motors to freely move the arm section while the arm section is manually moved; and a switch for selecting a type of teaching action.

Abstract: A system and method for interactively generating a family of mesh models is provided for use in engineering analysis. The system includes a user computer system having a memory, a processor, a user input device and a display device. The system also includes a remotely located computer system having a processor, a memory, and a data storage means and in communication with the user computer system. The system further includes a computer-generated geometric mesh base model stored in the data storage means, a computer-generated mesh feature stored in the data storage means, and a new mesh model including the base mesh model with a mesh feature that is stored in the data storage means. The method includes the steps of selecting a base model from a model library maintained in the data storage means. The method also includes the steps of creating a mesh feature that is defined by a modifiable set of parameters and saving the mesh feature in a mesh feature library maintained in the data storage means.

Abstract: A robot control unit for controlling a robot mechanism unit constantly detects the status of a robot and stores it as robot status data. An operation command input by voice from a head set is converted into character data by a voice/character data conversion device, and input to a control device. The control device searches a command corresponding to an operation command input in operation commands stored in management data. An executing program group is specified for link and storage with the corresponding operation command.

Abstract: A camera is fixed to a camera fixture extending forward and upward from a rear end of an arm mechanism. The camera picks up the direction of extension of the arm mechanism when the substrate is carried in and out. If a normal still image in a hot plate unit previously recorded and a still image picked up by the camera coincide with each other, a substrate transport robot TR carries in and out the substrate.

Abstract: In an automated data storage library having a plurality of accessors which access portable data storage media with respect to storage shelves and data storage drive(s) along a path, a controller, in response to detection of restricted movement of an accessor at a position along the path, determines a range of motion of another accessor along the path which avoids interfering with the accessor having the restricted movement. The controller also determines a limit to commands of a work queue of commands for operating the accessors, the limit extending from and past the position of the accessor having the restricted movement, along the path; and prevents execution of the limited commands. The limited commands may be failed with a “hardware” error.

Abstract: In a case in which an operation is alternately carried out by apparatus-1 and the apparatus-2 in cooperation with a robot, an operator carries out operation within an operation range of each of the apparatuses during the interruption of power supply to the apparatus-1 and the apparatus-2. Even if the operator approaches or enters the apparatus-1 or the apparatus-2, an emergency stop unit is not informed of a notice of such approach or entry as far as the interruption of power to the apparatus is confirmed. In a state in which the interruption of power is not confirmed, on the other hand, the emergency stop unit is informed of the notice of operator's approach or entry, and the robot system is emergency stopped.

Abstract: Robot platforms, methods, and computer media are disclosed. The robot platform includes perceptors, locomotors, and a system controller, which executes instructions for a robot to follow a target in its environment. The method includes receiving a target bearing and sensing whether the robot is blocked front. If the robot is blocked in front, then the robot's motion is adjusted to avoid the nearest obstacle in front. If the robot is not blocked in front, then the method senses whether the robot is blocked toward the target bearing and if so, sets the rotational direction opposite from the target bearing, and adjusts the rotational velocity and translational velocity. If the robot is not blocked toward the target bearing, then the rotational velocity is adjusted proportional to an angle of the target bearing and the translational velocity is adjusted proportional to a distance to the nearest obstacle in front.

Abstract: A method and a device are provided for detecting the occurrence of a malfunction upon movement of an element by a driving system. While the element is being moved, a difference between a predetermined value and an actual value is determined at regular intervals by means of a processor. A derivative of the difference is determined by the processor at regular intervals. The difference and the derivative both fluctuate around an equilibrium value. Subsequently, only the values on one side of the equilibrium value of both the difference and the derivative are sampled. The sampled values are multiplied and the result is compared with a reference value by means of the processor. The occurrence of a malfunction is established if the result of the multiplication is higher than the reference value.

Abstract: There is therefore provided, in accordance with a preferred embodiment of the present invention, a robotic system for systematically moving about an area to be covered. The system includes at least one boundary marker (48) located along the outer edge of the area to be covered, a robot (40) with a navigation system (41) and a sensor unit (43). The navigator system (41) navigates the robot (40) in generally straight, parallel lines from an initial location and turns the robot (40) when the robot (40) encounters one of the boundary markers (48), thereby to systematically move about the area to be covered. The sensor unit (43) senses proximity to one of the at least one boundary marker (48).

Abstract: A robot controller for teaching a robot with high efficiency. The robot controller including command storage unit (21) where a movement command and a work command are stored, command identifying unit (24) for discriminating between the movement and work commands, unit (22) for making/editing a series of work programs or discrete work programs by a combination of the commands, work program storage units (23) where the work programs are stored so as to control the robot according to the stored program, further including a work section identifying unit (25) for identifying a work section of the work program by way of the command identification unit (24) and work section automatic stopping unit (27) for automatically stopping or suspending the execution of the work program at the work section in a standby state when the work section identifying unit (25) identifies the work section during the execution of the work program.

Abstract: A temporary operation path is set by connecting a plurality of welding points in a virtual space generated by a computer to investigate whether an end effector can be operated along the temporary operation path. If the operation cannot be operated, a path to avoid interference with a workpiece is set automatically while extracting a portion in which the workpiece exists in the internal space surrounded by the end effector in order to set a narrow-area operation path for withdrawing the end effector from a welding point. Next, in order to set a wide-area operation path for making movement between withdrawing points, a template operation is applied, in which the end effector is moved by a prescribed distance in a prescribed direction.

Abstract: A library apparatus includes a storage shelf that has a plurality of cells for housing a cartridge that stores a plurality of recording media; a recording and reproducing unit that performs recording/reproducing of information to/from the recording media; and a conveying mechanism that conveys the cartridge to a predetermined position in the storage shelf, between the storage shelf and the recording and reproducing unit. The conveying mechanism includes a first conveying mechanism that conveys the cartridge during a normal operation of the library apparatus; and a second conveying mechanism that conveys the cartridge during an abnormal-operation of the first conveying mechanism.

Abstract: An autonomous robot, that is for example, suitable for operations such as vacuuming and surface cleaning includes a payload configured for vacuum cleaning, a drive system including a steering system, a navigation system, and a control system for integrating operations of the aforementioned systems.

Abstract: An electrical connection of a transfer station releasably, repeatably electrically couples with respect to a matching connection of a portable cartridge. A substrate in the portable cartridge has electrical contacts on a facing surface. In the transfer station, a matching circuitized flexible substrate has electrical contacts on a facing surface thereof, which are arranged to match the portable cartridge electrical contacts when in a face-to-face relationship. An elastomeric compression element, at the rear of the matching substrate, has individual protruding compression members contacting the rear surface and registered with corresponding individual electrical contacts. Elongated electrical contacts are registered with two adjacent individual compression members.

Abstract: A method for operating a data center with a robotic device. In the method, a condition is detected in a location of the data center. The robotic device, which includes a camera and a manipulator, is maneuvered to travel to the location of the data center. The location of the data center is imaged with the camera of the robotic device and an object is manipulated with the manipulator of the robotic device.

Abstract: A method for differentiating if a feedback signal is a result of an unintentional collisions in a servo system includes injecting a feed forward term in the servo system.

Abstract: Certain embodiments of the present invention relate to a collision detection system. The collision detection system includes a position indicator for determining an actual position of a component connected to the collision detection system. The system also includes an error calculator for determining a position error between the actual position and a selected position. The system further includes a comparator for comparing the position error to a position error limit. The comparator generates a halt signal based on the position error and position error limit. The system also includes a motion controller for controlling motion of the component. The motion controller stops motion of the component based on the halt signal. The comparator generates a halt signal when the position error is equal to or greater than the position error limit.

Abstract: A robot cleaner system for detecting an external recharging apparatus which is positioned in a non-detectable area by an upper camera thereof, and a docking method for docking the robot cleaner system with the external recharging apparatus. The robot cleaner system includes an external recharging apparatus with a power terminal connected to a utility power supply, a recharging apparatus recognition mark formed on the external recharging apparatus, and a robot cleaner, having a recognition mark sensor that detects the recharging apparatus recognition mark, and a rechargeable battery. The robot cleaner automatically docks to the power terminal to recharge the rechargeable battery. The recharging apparatus recognition mark is made of retroreflective material or a metal tape, and the recognition mark sensor may be a photosensor or a proximity sensor.

Abstract: A positioning data calculating procedure calculates analytically relative rotation angles for the links arranged in series to form an articulated manipulator to locate an object in a desired orientation at a desired position. Coordinate expressions including an x-coordinate expression representing the x-coordinate of a triaxial intersection point, a yz addition coordinate expression representing the sum of the y- and the z-coordinate of the triaxial intersection point, and a yz subtraction coordinate expression representing the remainder of subtraction of the z-coordinate from the y-coordinate of the triaxial intersection point, and including first to third rotation angles corresponding to rotation angles through which the second link is turned relative to the first link, through which the third link is turned relative to the second link, and through which the fourth link is turned relative to the third link as variables are solved.

Abstract: In an automated data storage library having a plurality of accessors which access portable data storage media with respect to storage shelves and data storage drive(s) along a path, a controller, in response to detection of restricted movement of an accessor at a position along the path, determines a range of motion of another accessor along the path which avoids interfering with the accessor having the restricted movement. The controller also determines a limit to commands of a work queue of commands for operating the accessors, the limit extending from and past the position of the accessor having the restricted movement, along the path; and prevents execution of the limited commands. The limited commands may be failed with a “hardware” error.