Collision Prevention Patents (Class 700/255)
  • Patent number: 6438459
    Abstract: Multiple intelligent pickers for an automated data storage library, the library having a library controller which identifies the start and end locations of the received move jobs, and places the move jobs in a job queue. The picker processor receives information over a communication link from other pickers describing movement information for the current move job of each of the other pickers. Upon completion of a move job, the picker communicates with the library controller, selecting a move job which avoids interference with the movement of the other pickers. The movement for the selected move job is determined so as to avoid interference with the stored movement profiles of the other pickers. A movement profile may be communicated to the other pickers over the communication link, and the move job is conducted according to the movement profile. Alternatively, movement information comprising the current location and vector are communicated.
    Type: Grant
    Filed: September 25, 2001
    Date of Patent: August 20, 2002
    Assignee: International Business Machines Corporation
    Inventors: Kamal Emile Dimitri, John Edward Kulakowski, Rodney Jerome Means
  • Patent number: 6430474
    Abstract: A system for manipulating a workpiece in an industrial robot system having a manipulator device for manipulating the workpiece, a tooling adapter coupled to the manipulator device for manipulating the workpiece, and an image referencing system for acquiring image data corresponding to the workpiece without interference from the manipulator device.
    Type: Grant
    Filed: April 3, 2001
    Date of Patent: August 6, 2002
    Assignee: Xerox Corporation
    Inventors: Christopher C. DiStasio, Nathaniel W. Haslam
  • Patent number: 6421579
    Abstract: Multiple intelligent pickers for an automated data storage library, the library having a library controller which identifies the start and end locations of the received move jobs, and places the move jobs in a job queue. The picker processor receives information over a communication link from other pickers describing movement information for the current move job of each of the other pickers. Upon completion of a move job, the picker communicates with the library controller, selecting a move job which avoids interference with the movement of the other pickers. The movement for the selected move job is determined so as to avoid interference with the stored movement profiles of the other pickers. A movement profile may be communicated to the other pickers over the communication link, and the move job is conducted according to the movement profile. Alternatively, movement information comprising the current location and vector are communicated.
    Type: Grant
    Filed: November 5, 1999
    Date of Patent: July 16, 2002
    Assignee: International Business Machines Corporation
    Inventors: Kamal Emile Dimitri, John Edward Kulakowski, Rodney Jerome Means
  • Patent number: 6377869
    Abstract: A robot controller having a function of monitoring abnormality of a robot operation to prevent an accident by stopping supply of energy or operational substance to an operational tool when the operational tool is abnormally stopped. Motion command pulses for a robot motion are obtained by computing operations when a motion statement of the operation program is read out and stored in a shared memory. Motors for driving respective robot axes are driven based on the motion command pulses. When an I/O output command is issued on a signal line to actuate an arc welder, the operation control software demands to set a predetermined waiting time period to a timer. The managing software demands to start a countdown of the timer and informs the operation control software of an elapse of the set waiting time period.
    Type: Grant
    Filed: June 29, 2000
    Date of Patent: April 23, 2002
    Assignee: Fanuc Ltd.
    Inventors: Atsushi Watanabe, Tetsuya Kosaka, Hiromitsu Takahashi
  • Patent number: 6374158
    Abstract: A robotic machine includes a machine tool removably supported in a mount for following a programmable path over a workpiece. A calibration pointer includes a housing configured like the tool for being supported in the mount, and a laser is affixed in the housing for emitting a laser beam at the workpiece. In a method of operation, the laser beam is projected from the laser in a focused spot at the workpiece at an offset therefrom. The spot permits accurate programming of the machine without contacting the workpiece.
    Type: Grant
    Filed: February 15, 2000
    Date of Patent: April 16, 2002
    Assignee: General Electric Company
    Inventor: Robert Anthony Fusaro, Jr.
  • Patent number: 6363300
    Abstract: Process for the automatic determination of an optimal movement program of a robot comprising at least one moving member, a motor associated with the moving member and a control unit capable of activating the motor according to a movement program to move the moving member along a trajectory with a predetermined movement parameter. The process comprises the steps of: acquiring data indicating the load state of the motor and the precision of movement of the robot during the execution of a movement program, comparing the information on the load state and on the precision of movement with predetermined limit values, repeatedly executing the movement program while progressively varying the movement parameter until a measured value of the load state and/or of the precision of movement exceeds a corresponding limit value, and storing as the optimal movement program the last movement program which has been executed without exceeding the limit values.
    Type: Grant
    Filed: March 28, 2000
    Date of Patent: March 26, 2002
    Assignee: Comau S.p.A.
    Inventor: Marco-Severo Inga
  • Patent number: 6356808
    Abstract: A method for cell alignment, identification and calibration of part of a robot tool, preferably a part of the robot tool, is positioned close to a detector, whereupon it is moved repeatedly past the limit of the area of detection of the detector. During the movement, the pose of the robot is registered each time the surface of said robot tool comes into tangential contact with the area of detection, and an over determined system of equations is formed, consisting of a correlation between the registered poses and unknown parameters regarding the detection area of the detector and the location of the robot part in space. An error vector is introduced into the system of equations, which is then solved while minimizing the error vector, preferably in the least square sense, in order to thus identify said unknown parameters and the error vector.
    Type: Grant
    Filed: June 4, 2001
    Date of Patent: March 12, 2002
    Assignee: Robotkonsult AB
    Inventor: Björn Stenberg
  • Patent number: 6351685
    Abstract: A wireless communication link provides picker to picker communication between multiple intelligent pickers for an automated data storage library, and provides central communication between at least one of the pickers with a central job queue. Each intelligent picker comprises a processor located thereon for operating the picker to conduct a move job and providing movement information describing movement of the picker for the current move job of the picker. The wireless communication link comprises a wireless central communication link between at least one of the pickers and a central job queue for communicating a move job to the picker processor from the central job queue, and a wireless picker to picker communication link for communicating between the pickers, each linked picker transmitting the movement information over the wireless picker to picker communication link.
    Type: Grant
    Filed: November 5, 1999
    Date of Patent: February 26, 2002
    Assignee: International Business Machines Corporation
    Inventors: Kamal Emile Dimitri, John Edward Kulakowski, Rodney Jerome Means
  • Publication number: 20020019683
    Abstract: Machine tools combine material addition via ultrasonic object consolidation and subtractive techniques for imparting high-dimensional accuracy to a finished object. A material supply and feeder, ultrasonic horn, and feedstock cutting device are integrated with a material removal subsystem preferably including a cutting tool and an excess material removal system. Any metal, plastic or composite material suitable for ultrasonic joining may be employed as a feedstock, and these material may assume the form of tapes, sheets, wires, filaments, dots or droplets, with the feeding and material cutting components being designed for the specific feedstock employed. The cutting tool for excess material removal, may be a knife, drill/mill, grinding tool, or other tool capable of accurately cutting the external contour of a cross section of the part being built, and for removing excess feedstock remaining following the application process.
    Type: Application
    Filed: May 17, 2001
    Publication date: February 14, 2002
    Inventors: Dawn White, David E.E. Carmein
  • Publication number: 20010051841
    Abstract: The present invention provides a processing machine having the function of sensitively detect collisions or other abnormalities to prevent the machine from being operated under abnormal conditions. Means 22 is provided for detecting a load on a drive source 1 for driving a movable member 2. Abnormality determining means 23 is provided for determining the load is abnormal if the lead as detected by the abnormality means 22 exceeds an abnormality determination level (Lb). The abnormality determining means 23 sets the abnormality determination level (Lb) on the basis of the load as measured during the preceding driving operation of the movable member 2 or the average of loads as measured during several past driving operations that are temporally close to the current one.
    Type: Application
    Filed: June 5, 2001
    Publication date: December 13, 2001
    Applicant: MURATA KIKAI KABUSHIKI KAISHA
    Inventor: Hidetsugu Kawai
  • Patent number: 6327516
    Abstract: Parameters of a robot is displayed on a display device of an operation terminal in a manner that parameters having been changed and parameters having not been changed of all the parameters are displayed in a distinguished manner such that the background color of the parameters having been changed differs from that of other data.
    Type: Grant
    Filed: April 12, 2000
    Date of Patent: December 4, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hideo Zenke
  • Patent number: 6322733
    Abstract: A method and an apparatus are disclosed for controlling a motional sequence of a first movable component of a plastic material injection molding machine having a first trajectory spatially overlapping at least partially a second trajectory of a second movable component of the plastic material injection molding machine. Motion of the first movable component is initiated depending on an enabling signal indicative for a motional state of the second movable component.
    Type: Grant
    Filed: October 15, 1999
    Date of Patent: November 27, 2001
    Assignee: Hekuma Herbst Maschinenbau GmbH
    Inventor: Richard Herbst
  • Patent number: 6324437
    Abstract: A system and method for managing garment alterations. The system includes a workroom processor having a display and operating a garment alteration application system. Alterations tickets are created using a garment alterations ticket terminal, or display interfaces on the workroom processor that prompt the user for garment alteration data. The alteration data is stored in an alteration ticket data structure that relates to the workflow of a typical workroom. Alterations tickets are presented in the ticket list from which the alteration ticket status updated according to work performed. The reports module generates corporate and workroom management reports based on data stored in relation to the alterations.
    Type: Grant
    Filed: December 22, 1999
    Date of Patent: November 27, 2001
    Assignee: New Century Information Services, Inc.
    Inventors: Charles Frankel, Fang Zhong Ding, Timothy J. Findlow, Robert M. Millman
  • Patent number: 6321139
    Abstract: An operation line searching method in which an operation start position is automatically approached and a robot/sensor system having such function of detecting the operation line. A robot having a laser sensor and an operation tool attached to a distal end thereof approaches an operation start position Q1 using various searching motion path patterns (a) to (d). Pattern (a) is determined to avoid an obstacle F or an obstructively-shaped portion G. The path thereof, for example, can be determined by specifying a coordinate axis of a coordinate system w. Patterns (b) and (c) are carried out by teaching, to the robot, data for determining the paths thereof in order. Pattern (d) is carried out in the following manner: an initial parameter <V1>, an angle of rotation and a norm increase factor are specified as parameters, and at the time when incremental travel quantity of a (i+1)th occurrence (i=0, 1, 2, . . .
    Type: Grant
    Filed: November 30, 1998
    Date of Patent: November 20, 2001
    Assignee: Fanuc Ltd.
    Inventors: Akihiro Terada, Mitsuhiro Okuda
  • Patent number: 6321137
    Abstract: A system for calibrating a robot used for inspecting a workpiece to maintain the accuracy of the robot during inspection of workpieces on a production basis, the system including means for storing a mathematical model of the robot, means for measuring the position of a target and then calibrating the robot based upon input from the mathematical model and the position of the target.
    Type: Grant
    Filed: February 15, 2000
    Date of Patent: November 20, 2001
    Assignee: Dynalog, Inc.
    Inventor: Pierre De Smet
  • Patent number: 6308110
    Abstract: A modular object handling system has a multi-level control architecture, which includes a system controller that coordinates the functions and/or operations of individual module controllers, that in turn control corresponding actuators, to provide a desired system function. The system controller performs the overall trajectory planning by taking the constraints of each of the module actuators into account. The system controller may compensate for deviations of objects from their planned trajectories by contemporaneously redetermining trajectories and trajectory envelopes to encode the various combinations of the system constraints and task requirements. The trajectory envelopes can denote regions around other trajectories to indicate control criteria of interest, such as control and collision boundaries.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: October 23, 2001
    Assignee: Xerox Corporation
    Inventor: Markus P. J. Fromherz
  • Patent number: 6298283
    Abstract: An industrial robot capable of preventing re-collision after colliding with an obstacle. Disturbing torque exerted on each servomotor for a robot axis is estimated by its associated disturbance estimating observer. When a hand attached to an end of a robot arm collides with an obstacle, an estimated value of disturbance given by a disturbance estimating observer exceeds a predetermined threshold, and the collision is detected. Then, each motor for driving a robot arm is drivingly controlled with a velocity command turned to “0”. Each motor for driving the robot hand is driven with torque having a predetermined magnitude (maximum magnitude) and the same sign as that of an estimated value of disturbing torque exerted on it, for a predetermined time, and then it is brought to an emergency stop. Thus, after colliding with an obstacle, the robot hand is driven in a direction such that it recedes from the obstacle.
    Type: Grant
    Filed: December 27, 1999
    Date of Patent: October 2, 2001
    Assignee: Fanuc Ltd.
    Inventors: Tetsuaki Kato, Yukinobu Tsuchida
  • Patent number: 6292716
    Abstract: Several methods and subsystems are provided for aligning a workpiece as it is being loaded into a die space of a bending apparatus, and for performing sensor-based control of a robot as it moves a workpiece from one location to another within a bending apparatus environment. A backgaging mechanism is provided with finger gaging mechanisms having force sensors for sensing forces in directions perpendicular to and parallel to a die. In addition, a robot gripper sensor is provided for sensing either or both of shear forces and normal forces created by movement of a workpiece being held by the gripper.
    Type: Grant
    Filed: September 13, 1999
    Date of Patent: September 18, 2001
    Assignees: Amada America, Inc., Amada Company, Ltd.
    Inventors: Richard M. Moore, Jr., David Alan Bourne, Kerry L. Elkins, Anne Marie Murray, Robert H. Sturges, Jr., Kensuke Hazama
  • Patent number: 6289263
    Abstract: A spherical robot having a spherical body and a drive mechanism. The spherical body defines a cavity and a center. The drive mechanism is disposed within the cavity, coupled to the spherical body, wherein said drive mechanism includes a plurality of masses coupled to said body which are radially positionable within said cavity to create a moment about said center of said body, and is adapted to create a moment about the center of the body. This moment causes the body to rotate.
    Type: Grant
    Filed: December 15, 1998
    Date of Patent: September 11, 2001
    Assignee: Board of Trustees operating Michigan State University
    Inventor: Ranjan Mukherjee
  • Patent number: 6289264
    Abstract: A debugging system in which, when any trouble occurs in robot program using variables and debugging is to be performed, a specific variable as the probable cause of the trouble and a relevant reference variable are specified, and presence or absence of the specific variable in the called-up robot program is detected. When any specific variable appears, the values of the specific variable and the reference variables are acquired and displayed together with the robot program information.
    Type: Grant
    Filed: June 27, 2000
    Date of Patent: September 11, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hideo Zenke
  • Patent number: 6282460
    Abstract: A method for preventing collisions between robots by causing a first robot to stop or pause so that a second robot may safely pass by or perform a specified operation. Once the second robot has completed its operation then the first robot is allowed to resume operation. Each robot automatically stops when it reaches a certain point in its job. The robots communicate with a central controller which allows the robots to resume operation when the central controller has determined that all of the robots have reached their respective correct positions. This prevents collisions between robots which are operating in the same area, especially those robots operating on the same workpiece. This method works with existing robot welders, does not require modifications to the robots, and does not require expensive spatial analysis computer programs, which may not even be available for the type of processor used in a particular robot.
    Type: Grant
    Filed: January 29, 2001
    Date of Patent: August 28, 2001
    Inventors: Malcolm T. Gilliland, Kenneth Alan Gilliland
  • Patent number: 6278903
    Abstract: A robot body (21) is carried into the water chamber (2A) of a condenser (1) and disposed on a tube sheet (4) through which a number of narrow tubes (3) open. Inner nozzles (23) are inserted into narrow tubes (3) from working devices (24) installed on the front ends of four combined-use arms (22A through 22D) to position and fix the robot body (21). And the arm turning motors (25) and arm extending and contracting cylinder devices (26) of the combined-use arms (22A through 22D) are driven to move the robot body (21). Further, a cleaning brush (12) and a flaw detection probe (13) are inserted into a narrow tube (3) from each working device (24) and moved along the narrow tube (3) by cleaning water, whereby cleaning and inspection are performed. With three of the combined-use arms (22A through 22D) fixed to the narrow tubes (3), the inner nozzle (23) is extracted from the narrow tube (3) and the working device is moved to the next narrow tube (3).
    Type: Grant
    Filed: December 20, 1999
    Date of Patent: August 21, 2001
    Assignee: Hitachi Zosen Corporation
    Inventors: Hisashi Iwasaki, Shuji Komada, Hirotaka Takahashi, Minoru Hyuga, Takashi Fujimura
  • Patent number: 6278907
    Abstract: A modular object handling system has a multi-level control architecture, which includes a system controller that coordinates the functions and/or operations of individual module controllers, that in turn control corresponding actuators, to provide a desired system function. The system controller performs the overall trajectory planning by taking the constraints of each of the module actuators into account. The system controller may compensate for deviations of objects from their planned trajectories by contemporaneously redetermining trajectories and trajectory envelopes to encode the various combinations of the system constraints and task requirements. The trajectory envelopes can denote regions around other trajectories to indicate control criteria of interest, such as control and collision boundaries.
    Type: Grant
    Filed: November 24, 1999
    Date of Patent: August 21, 2001
    Assignee: Xerox Corporation
    Inventors: Markus P. J. Fromherz, Sudhendu Rai
  • Patent number: 6256556
    Abstract: A remote operation system for a robot for facilitating the restoring operation of the robot. In the system, when an abnormal operation or abnormal parameter on a user side is detected, the information of such an abnormality is displayed on the operation terminal of a service staff side and further operation instruction and comments relating to the restoring operation are applied from the service staff side to the operation terminal of the user side and displayed thereon.
    Type: Grant
    Filed: May 25, 2000
    Date of Patent: July 3, 2001
    Assignee: Mitsubishi Denki Kabushiki Kaisha
    Inventor: Hideo Zenke
  • Publication number: 20010004718
    Abstract: A method for preventing collisions between robots by causing a first robot to stop or pause so that a second robot may safely pass by or perform a specified operation. Once the second robot has completed its operation then the first robot is allowed to resume operation. Each robot automatically stops when it reaches a certain point in its job. The robots communicate with a central controller which allows the robots to resume operation when the central controller has determined that all of the robots have reached their respective correct positions. This prevents collisions between robots which are operating in the same area, especially those robots operating on the same workpiece. This method works with existing robot welders, does not require modifications to the robots, and does not require expensive spatial analysis computer programs, which may not even be available for the type of processor used in a particular robot.
    Type: Application
    Filed: January 29, 2001
    Publication date: June 21, 2001
    Inventors: Malcolm T. Gilliland, Kenneth Alan Gilliland
  • Patent number: 6249718
    Abstract: A method for automatically tracking the joint between a first component and a second component, or the edge of a component, a welding operation. A preliminary path is defined for the joint or edge (703), a welding torch (100) is moved along the preliminary path while an arc welding current is provided to the welding torch. The welding torch is moved slightly to a first side (705A) of the preliminary path and then to a second side (705B) of the preliminary path as the welding torch is being moved along the preliminary path. A first current measurement is obtained by measuring the arc welding current when the welding torch is to the first side, and a second current is obtained by measuring the arc welding current when the welding torch is to second side. The first current measurement and the second current measurement are compared and used to redefine the preliminary welding path by moving the welding torch slightly to the side having the preferred current measurement.
    Type: Grant
    Filed: May 24, 1999
    Date of Patent: June 19, 2001
    Inventors: Malcolm T. Gilliland, Kenneth Alan Gilliland
  • Patent number: 6243621
    Abstract: A method of determining position information of a workpiece relative to a robot includes the ability to move the workpiece into a variety of orientations relative to the robot during the touch sensing location procedure. The position information is then used for performing a robot operation including coordinated motion. A coordinated reference frame is defined with respect to a moveable positioner that supports the workpiece. Known kinematic relationships between the positioner and the robot are used to control operation of the robot within the coordinated reference frame throughout the touch sensing location procedure. By moving the workpiece relative to the robot during the touch sensing location procedure, a greater variety of workpieces can be processed and relatively complicated workpiece configurations can be accurately determined. The robot operating parameters are modified according to the determined position information.
    Type: Grant
    Filed: March 13, 1998
    Date of Patent: June 5, 2001
    Assignee: FANUC Robotics North America, Inc.
    Inventors: Jianming Tao, Jason Tsai, Robert A. Bolhouse
  • Patent number: 6230075
    Abstract: A library apparatus of the present invention has directors which respectively determine operations of two carrying devices traveling along one traveling path. A servo control units move the carrying devices based on the determination of the directors. The serv control units obtain positional data of the carrying devices, and judge whether or not the carrying devices come into contact with each other by comparing these pieces of positional data. The servo control unit, when judging that the carrying devices come into contact with each other, stops a driving circuit of each carrying device. A drive of a motor for supplying each carrying device with power is thereby stopped, and the carrying device is stopped.
    Type: Grant
    Filed: March 31, 2000
    Date of Patent: May 8, 2001
    Assignee: Fujitsu Limited
    Inventors: Hiroaki Nishijo, Shinobu Sasaki
  • Patent number: 6226569
    Abstract: A rotary transmitter for registration of the steering angle of a motor vehicle, with a transmitter component (49) on which is provided a coding (51) of a predetermined number n of locally sequentially digital words (Wi) with a width of m bits (b1, b2, . . , Bm) in m adjacent to each other tracks, at least one detector (55) for essentially simultaneous registration of the individual bits (b1, b2, . . . , Bm) of a digital word (Wi), whereby the transmitter component (49) and at least the one detector (55) are movable relative to each other, and with an evaluation unit (11) to which is conducted the signal of at least the one detector (55). The evaluation unit (11) ascertains the absolute position of the transmitter component (49) relative to at least the one detector (55), at least one time, by evaluation of a predetermined number (p) of sequentially detected digital words (Wi), whereby the evaluation unit (11) assigns to a detected p-measure (Wi, Wi+1, . . .
    Type: Grant
    Filed: October 20, 1999
    Date of Patent: May 1, 2001
    Assignee: TRW Automotive Electronics & Components GmbH & Co. KG
    Inventors: Cornelius Peter, Wolfgang Huber, Trevor Stewart, Zdenek Pavlis, Danilo Caratto
  • Patent number: 6212444
    Abstract: A method of preventing interference of an industrial robot in which teaching of an operation program to the robot is easy and interference of the robot with an external cooperative apparatus can be easily avoided. If a current position of a reference point on the robot for detecting interference is outside a common area (S12) and a target position of the reference point is outside the common area (S18), a motion command is outputted to drive the robot. If the target position of the reference point is within the common area, it is determined that whether or not a movable part of the cooperative apparatus is within the common area, and if the movable part is outside the common area, an operation forbidding signal for the cooperative apparatus is turned on and the motion command is outputted to make the robot move. If the movable part of the cooperative apparatus is within the common area, the motion command is withheld till the movable part of the cooperative device moves out of the common area (S4, S5).
    Type: Grant
    Filed: February 18, 1998
    Date of Patent: April 3, 2001
    Assignee: Fanuc Limited
    Inventors: Tetsuaki Kato, Atsuo Nagayama
  • Patent number: 6185480
    Abstract: An interference preventing method for industrial robots comprising a step (II) of reading a present position of the hand, a step (III) of computing the difference between the taught target position and the present position of the hand, a step (IV) of judging whether this difference is within a predetermined range or not, a step (V) of setting a moving speed of the hand to a predetermined normal speed when the difference is within the predetermined range, a step (VI) of setting the moving speed of the hand to a predetermined low speed when the difference is out of the predetermined range, and a step (VII) of moving the hand automatically to the target position at the set speed. When the hand is moved over a long distance in the case of which interference is liable to occur, the moving speed thereof is low; when the hand is moved over a short distance, the moving speed thereof is normal.
    Type: Grant
    Filed: December 12, 1997
    Date of Patent: February 6, 2001
    Assignee: Toyo Kohan Co., Ltd
    Inventors: Toshiyuki Takahashi, Atsushi Nakajima, Yukimasa Shiomichi
  • Patent number: 6173215
    Abstract: A method is disclosed for responding to the detection of an obstacle in the path of a mobile machine as the mobile machine traverses the path at a work site. The method includes the steps of scanning a field of interest, detecting the presence of an obstacle, and determining a set of parameters as a function of the mobile machine, the obstacle, and the work site. The method also includes the steps of determining a level of predictability of motion of the obstacle, defining ranges of a plurality of zones as a function of the level of predictability and the parameters, and initiating an action in response to the obstacle being in one of the zones.
    Type: Grant
    Filed: December 19, 1997
    Date of Patent: January 9, 2001
    Assignee: Caterpillar Inc.
    Inventor: Jagannathan Sarangapani
  • Patent number: 6167142
    Abstract: In an object movement simulation apparatus, a collision arithmetic unit performs arithmetic including a detection of two closest points in accordance with information representative of a plurality of objects. An image producing unit produces a three-dimensional image including a virtual object representative of a closest line coupling the two closest points to each other. The image producing unit produces the three-dimensional image, where a viewpoint is moved in a direction vertical to the closest line, looking at the viewpoint after a movement.
    Type: Grant
    Filed: April 28, 1998
    Date of Patent: December 26, 2000
    Assignee: Fujitsu Limited
    Inventor: Naoyuki Nozaki
  • Patent number: 6161058
    Abstract: A library apparatus of the present invention has directors which respectively determine operations of two carrying devices traveling along one traveling path. A servo control units move the carrying devices based on the determination of the directors. The serv control units obtain positional data of the carrying devices, and judge whether or not the carrying devices come into contact with each other by comparing these pieces of positional data. The servo control unit, when judging that the carrying devices come into contact with each other, stops a driving circuit of each carrying device. A drive of a motor for supplying each carrying device with power is thereby stopped, and the carrying device is stopped.
    Type: Grant
    Filed: January 30, 1998
    Date of Patent: December 12, 2000
    Assignee: Fujitsu Limited
    Inventors: Hiroaki Nishijo, Shinobu Sasaki