Abstract: A dual-loop torque sensing system includes four position sensors disposed in the motor and the reduction drive to form a dual-loop for detection to calculate the output torques. The detection of the position sensors is for confirming abnormality of the dual-loop or the position sensors. A failure alarm is issued to enhance the safety of the working environment.

Abstract: The invention relates to a camera arrangement, in particular for a vehicle, having a movably mounted camera unit which can be moved between a passive position and an active position, characterized by a cable system attached to the camera unit, which is operatively connected to a cable winch that can be rotated about an axis of rotation.

Abstract: A pneumatic robotic tool, such as grinder, sander, etc., implements passive force control and compliance using two or more double-acting pneumatic pistons distributed about a pneumatic motor within the tool housing. The multiple pistons facilitate a compact design, reducing tool stack height, as compared to prior-art, single-piston designs. In one embodiment, filtered breather vents and an air pressure equalization passage maintain ambient atmospheric pressure throughout the tool, while preventing the infiltration of dust and other particulates. In one embodiment, a hard port rigidly affixed to the tool housing is provided for at least motor supply pneumatic fluid. The motor supply air is transferred from the hard port to the pneumatic motor via a flexible pneumatic fluid tube within the tool housing. In one embodiment, the pneumatic motor discharge air is vented from the tool housing in a sealed passage that accommodates the tool compliance motion, and prevents dust infiltration.

Abstract: There is disclosed in one example an inner loop controller for an aircraft flight computer, including: a stall protection circuit to compute, for an attitude angle ?, an attitude limit ?max as a function of a flight path angle (?) and an angle of attack limit (?max); a transfer function circuit to convert ? to an attitude rate {dot over (?)}, wherein {dot over (?)} is a time derivative of ?; and a load protector circuit to compute a limit on {dot over (?)} ({dot over (?)}max) as a function of a load factor limit (Nz,max) and a true airspeed (v).

Abstract: In a method for monitoring an operating behavior of a tool holder, a resultant measurement axis signal is calculated using at least two measurement axis signals of at least two radially oriented measurement axes of a sensor provided in the tool holder. The monitoring is performed using the resultant measurement axis signal or the resultant.

Abstract: Cable-driven robotic platform systems and methods of operation are disclosed. The system includes a robotic platform suspended by a system of overhead cables, motorized cable reels and pulleys. A master control computer coordinates operation of the motorized cable system as a function of sensor data captured by navigation sensors on-board the platform so as to move the robotic platform inside an industrial plant. The system is configured to maneuver around pipings and avoid obstacles in the plant in order to maximize the effective workspace that the robotic platform can reach to perform operations including inspection or repair. Additionally, a robotic “wire jacket” device can be attached to suspension cables and configured to crawl along a cable. The wire-jacket can be selectively positioned on a cable to provide an intermediate cable suspension point that improves platform mobility within congested spaces and avoids obstacles.

Abstract: The present invention refers to an automated painting system on oil ships, being executed by a mobile platform and an oscillating arm. The assembly only works due to the control of cables, winders and wheels. This approach is aimed at painting large vertical walls. The painting deck suspension uses four cables, each connected to a pivot on the mobile platform, and two fixed pivots plus four winders. The winders contain a servo motor in a synchronous serial network. The cables are made of reduced-weight polyethylene. Each cable is connected exclusively to one winder. Suspension is achieved with the aid of two adapted cranes and initialization through the addition of a giraffe-type crane.

Abstract: An alarm notification system configured to assist an operator so that the operator can effectively carry out a teaching operation, etc. The alarm notification system includes: a storing section configured to, with respect to a past alarm which occurred when a program generated by a teach pendant was executed, store alarm data including a name of the program and a number of a line of the program when the alarm occurred; a judging section configured to judge as to whether or not an alarm prediction condition using the alarm data stored in the storing section is satisfied, when the program is executed again; and an alarm predicting section configured to notify the operator who is carrying out teaching of the robot of alarm information relating to the alarm, when the alarm prediction condition is satisfied.

Abstract: A method comprises displaying a surgical environment image. The surgical environment image includes a virtual control element for controlling a component of a surgical system, and the virtual control element includes a real-time image of the component of the surgical system in the surgical environment image. The method further comprises displaying an image of a body part of a user. The body part is used to interact with the virtual control element. The method further comprises receiving a gesture of the body part of the user in a predetermined motion, via a gesture based input device registering movement of the body part of the user, while the body part interacts with the virtual control element. The method further comprises adjusting a setting of the component of the surgical system based on the received gesture.

Abstract: A lifting support device that includes a linear actuator including a first end configured to support an object, and a load sensor positioned to determine application of a first load on the load sensor by at least the object. The linear actuator is maintained in equilibrium when supporting the first load. The lifting support device further includes a controller coupled in communication with the load sensor, and the controller is configured to selectively actuate the linear actuator in response to application of a second load on the load sensor.

Abstract: A powered user interface for a robotic surgical system includes a handle on a linkage having a plurality of joints, a base, and actuators. The interface operates in accordance with a first mode of operation in which a plurality of its actuators are operated to constrain predetermined ones of the joints to permit motion of the handle in only 4DOF with respect to the base, and a second mode of operation in which the actuators permit motion of the handle in at least 6DOF with respect to the base.

Abstract: Provided is an offshore crane heave compensation control system and method using video rangefinding to achieve heave compensation in a directly driven pump-controlled electro-hydraulic heave compensator. The heave compensation and the heave compensator are applicable for special operation and control requirements on a fixed offshore platform and allow the crane to achieve steady lifting of a load away from or lowering of a load on to a supply vessel without being influenced by the motion of the supply vessel caused by ocean currents, ocean winds, or ocean waves. Also provided is a test platform for the offshore crane heave compensation control system using video rangefinding. The test platform provides a realistic simulation for all lifting and lowering processes of an offshore platform crane in offshore environments to study the motion control of the provided system.

Abstract: The present invention relates to a lithographic apparatus, comprising: —a primary frame (10) which is provided with a functional unit (11, 12, 14), —a secondary frame (20), —a primary frame support (30), which is adapted to support the primary frame onto the secondary frame, —a flexible utility connection (40), adapted to connect the functional unit to an auxiliary system (51, 52, 53), —a vibration isolation body (60) having a body mass, which is moveably connected to the secondary frame by a flexible passive body support (61) having a body support stiffness, wherein the flexible utility connection is fixed to the vibration isolation body at a distance from the primary frame.

Abstract: A parallel link robot includes a movable portion, a base, a plurality of drive sources, a plurality of links, and a tension member. The plurality of drive sources is attached to the base. The plurality of links is respectively connected to the plurality of drive sources. The tension member is connected between the movable portion and at least one of the plurality of links such that a bending tension is generated.

Abstract: A gimbal for a robotic surgical system includes a support link, an input link, and a vibration assembly. The input link extends from the support link and the vibration assembly is mounted to the support link. The vibration assembly includes a central support, an end cap, and a voice coil. The end cap is moveable relative to the central support. The voice coil has an inner member that is fixed to the central support and an outer member that is fixed to the end cap. The voice coil is configured to vibrate the gimbal in response to a voltage being applied to one of the inner or outer members.

Abstract: Methods, apparatus, and computer readable media applicable to balancing robots. Some implementations are directed to maintaining a given end effector pose (relative to a world frame) of an end effector of a balancing robot when there is a disturbance to a balancing base of the balancing robot. Some implementations are additionally or alternatively directed to transitioning a balancing robot from a fallen configuration to a balanced configuration. Some implementations are additionally or alternatively directed to mitigating the risk that a balancing robot will fall when interacting with actuable environmental objects (e.g., doors) and/or to lessen the disturbance to a balancing base when interacting with actuable environmental objects.

Abstract: A device for cutting a workpiece along a cutting line between a first end point and a second end point including a saw head, comprising an advancing mechanism with a guide carriage and with an advancing motor. The saw head is arranged on the guide carriage movable along an advancing direction, including a sensor system with a sensor element for monitoring the saw head, the advancing mechanism or the work process, including a control unit with a control element to control the saw head, the advancing mechanism and the sensor system as well as an evaluation element to evaluate a measured quantity detected by the sensor system, including an operating device to operate the saw head and the advancing mechanism, and including a display. On the basis of the measured quantity, the control unit calculates the momentary work result which is shown on the display.

Abstract: Systems and methods are provided for coupling a robotic surgical tool with a tool driver of a robotic surgical system via a sterile barrier disposed between the tool and the driver. The tool has an elongate shaft and an end effector coupled thereto, as well as a mating interface member having a plurality of independently movable portions and a plurality of coupling features disposed about a perimeter of an outer wall of the mating interface member. The coupling features are configured to reversibly engage with a proximal end of a corresponding actuation member from a plurality of actuation members of the tool driver. The coupling features reversibly engage with the proximal ends of the actuation members so as to allow the actuation members to move in proximal and distal directions independently from one another to thereby control operation of the end effector.

Abstract: A collision stress releasing device reversely rotates a feed motor by a return amount set in a return amount setter based on a contact position of a movement unit or a collision detection position regarded as a contact position. Generally, a large error does not occur even when the collision detection position is regarded as the contact position, but when the movement unit or the colliding member has low rigidity, a control of setting a return amount in response to the speed of the movement unit or a control of estimating an actual contact position from a rise curve of a load after a collision is more desirable.

Abstract: Systems and methods are provided for coupling a robotic surgical tool with a tool driver of a robotic surgical system via a sterile barrier disposed between the tool and the driver. The tool has an elongate shaft and an end effector coupled thereto, as well as a mating interface member having a plurality of independently movable portions and a plurality of coupling features disposed about a perimeter of an outer wall of the mating interface member. The coupling features are configured to reversibly engage with a proximal end of a corresponding actuation member from a plurality of actuation members of the tool driver. The coupling features reversibly engage with the proximal ends of the actuation members so as to allow the actuation members to move in proximal and distal directions independently from one another to thereby control operation of the end effector.

Abstract: An inverter control device that controls an inverter unit that converts a DC voltage from a converter unit to an AC voltage and supplies the AC voltage to the DC motor includes a storage unit that stores therein information regarding a synchronization-loss limit; a synchronization-loss limit-current calculation unit that calculates the limitation value on the synchronization-loss limit current on the basis of the magnet temperature of the DC motor, the bus voltage to be applied to the inverter unit, and the information regarding a synchronization-loss limit; and a control unit that compares the primary current to be input to the converter unit with the limitation value and that, when the primary current exceeds the limitation value, outputs an adjustment command to adjust the operating frequency of the DC motor such that the primary current becomes equal to or less than the limitation value.

Abstract: An integrated IC provided in an SBW-ECU has plural functions such as a receiving function of receiving output signals of an encoder and a current supply function of supplying current to each phase of the motor. A microcomputer checks individually whether the signal receiving function and the current supply function are potentially abnormal and checks whether the integrated IC is abnormal based on the check results about the signal receiving function and the current supply function. For example, when it is determined that only the signal receiving function of the integrated IC is potentially abnormal, the encoder is determined to be abnormal. When it is determined that the signal receiving function and the current supply function of the integrated IC are both potentially abnormal, the integrated IC is determined to be abnormal.

Abstract: A robot apparatus 1 includes: a multi-articulated robot 2; and a controller 3 that drive-controls the multi-articulated robot 2 based on an input motion command. The controller 3 includes: a joint angle computing unit 32 that computes each joint angle command for driving the multi-articulated robot 2 based on the motion command; a servo controlling apparatus 30 that moves the multi-articulated robot 2 by rotationally driving each rotational joint based on the joint angle command computed by the joint angle computing unit 32; a singular point calculating unit 51 that calculates a distance between the multi-articulated robot 2 and a singular point of the multi-articulated robot 2; and a maximum joint angle deviation adjusting unit 52 that limits a maximum rotation speed of a rotational joint specified in advance based on a singular point type, if the singular point distance becomes smaller than a predetermined value.

Abstract: A manipulator, such as for use in medical procedures, is provided. The manipulator includes a body and a first actuator system connected to the body at a first attachment point and capable of moving the first attachment point with at least three degrees of freedom. A second actuator system is connected to the body at a second attachment point and capable of moving the second attachment point with at least three degrees of freedom. A third actuator system is integrated with the body and is capable of moving at least a portion of the body with at least one degree of freedom.

Abstract: A collision detection method for a drive unit including an electric drive motor and a movable component which is driven thereby, wherein an actual torque and an actual acceleration of the electric drive motor are sensed and a collision of the movable component is detected on the basis of an evaluation of a predefinable mathematical combination of the actual torque and the actual acceleration.

Abstract: The present invention provides a lithography apparatus for forming a pattern on a substrate, including a motor configured to drive a table for holding the substrate in accordance with a driving profile, a setting unit configured to set one of a normal mode and a power saving mode as an operation mode of the motor, and a controller configured to change the driving profile when the power saving mode is set, such that an amount of generated heat of the motor caused by driving of the table is smaller than that in the normal mode, and the number of substrates to be processed by the lithography apparatus per unit time is satisfied.

Abstract: A method for determining a status of at least one machine includes the following steps: a processing unit is utilized to receive and record spindle load values of the spindle in a period of time to generate a spindle load record of the spindle, and to determine if a preset condition is matched according to the spindle load record. When the preset condition is matched, the processing unit is utilized to determine a present category corresponding to the spindle load record of the spindle, and to obtain parameter-to-be-collected information corresponding to the present category. The processing unit is utilized to obtain at least one value of at least one collected parameter of the at least one machine according to the parameter-to-be-collected information corresponding to the present category, and to determine a status of the at least one machine according to the obtained value of the at least one collected parameter.

Abstract: In one implementation, a method is disclosed in which a lock sensing mode is entered for a robotic surgical instrument. In the lock sensing mode, the degrees of freedom of movement in the robotic surgical instrument are switchably reduced. Further in the lock sensing mode, one or more end effectors of the robotic surgical instrument are switchably clamped together in the robotic surgical instrument. An increased level of torque may also be applied to the end effectors to increase a gripping force applied by the one or more end effectors in response to the reduced degrees of freedom of movement in the robotic surgical instrument.

Abstract: A motor control apparatus includes a torque-limit output unit configured to output a torque limit with which power consumption of a motor is equal to or smaller than a predetermined motor power limit value and voltage amplitude required for driving the motor is equal to or smaller than a predetermined voltage limit, a position-command generating unit configured to generate a position command to a reference position according to the torque limit value, and a power/voltage limiting unit configured to perform processing for correcting a motor torque current on the basis of an excess of the motor power consumption with respect to a motor power consumption limit value and processing for correcting a motor excitation current on the basis of an excess of a motor torque divided voltage with respect to a motor torque divided voltage limit value.

Abstract: This disclosure discloses a motor control device including a main circuit, a voltage detector, and a controller. The controller includes a position controller and a speed controller, The position controller generates a speed command The speed controller generates a torque command and controls a inverter based on the torque command Further, the controller includes a torque limiter, and a speed matching instruction part. The torque limiter starts torque limiting by the torque command to a predetermined torque or less and cancels the torque limiting. The speed matching instruction part matches the speed command with a first position command speed after the cancellation of the torque limiting. The holding part calculates and holds an accumulated position deviation.

Abstract: A motor control apparatus includes, a converter which converts input AC to DC for output, an inverter which converts the DC output of the converter to provide an AC output for driving a motor, and an inverter control part for controlling the same, and a numerical control part which outputs a motor operation command for commanding the operation of the motor, and wherein when AC current or power input to the converter lies outside a predetermined range, the inverter control part controls the AC output of the inverter so that the motor is operated in accordance with a limited torque command produced by limiting a torque command originally specified in the motor operation command.

Abstract: When a short-circuited FET is identified as one of low-side FETs, maximum phase voltages of three phases are detected when a steering operation is performed by a driver, and the detected maximum phase voltages of the three phases are compared with one another to identify a short-circuit phase. On the other hand, when a short-circuited FET is identified as one of high-side FETs, minimum phase voltages of the three phases are detected when a steering operation is performed by the driver, and the detected minimum phase voltages of the three phases are compared with one another to identify a short-circuit phase.

Abstract: The present invention is aimed to realize a method and a system for controlling an electric cylinder by which the load detector that is attached to an electric cylinder and the rod of the cylinder can avoid being overloaded. An unexpected bump between the rod of the cylinder and the material to be pressed can cause that overload. A servo controller 17 determines whether the load for pressurizing Pm detected by the load detector 13 is larger than or equal to the load for detecting a bump Pc. If it is determined that the load for pressurizing Pm is larger than or equal to the load for detecting a bump Pc, the servo controller 17 determines whether the flag for stopping is ON. Also, the controller 17 determines whether the speed Sm of the rod 11 is greater than or equal to an allowable speed to bump Sc.

Abstract: A control system of a servo press and a control method are provided for preventing an overload on a pressure capability of a press and a torque capability of a drive system. A control device of a servo press for pressing by transferring a drive force of a servomotor to a slide via a drive mechanism includes: a motion calculation unit for calculating slide target position data; a torque calculation unit for calculating process torque for pressing and control torque for speed change of the servo motor on the basis of slide target position data; a process system limit unit for limiting the calculated process torque to predetermined process limitation torque; and a drive system limit unit for limiting combined torque of the limited process torque and the control torque to predetermined drive limitation torque. The servo motor is driven on the basis of a command of drive limitation torque.

Abstract: An electric chain saw has an electric drive motor defining a motor-specific characteristic line of the drawn-in current as a function of the rotational speed of the motor. A control unit controls the current flowing through the drive motor below an engaging rotational speed to values below the motor-specific characteristic line. In order to generate an operating point the operator can feel in a working region in a predetermined rotational speed band, a control characteristic line of the electric input power of the electric drive motor as a function of the rotational speed is provided above the engaging rotational speed. The control characteristic line is adapted to reduce the electric input power within the rotational speed band to an approximately even mean power so as to cause the torque of the drive motor to increase within the rotational speed band with falling rotational speed.

Abstract: If it is predicted that the sum of the output of a servo motor and the output of a spindle motor exceeds power supplied by a rectifier unit, during a cutting operation, a motor drive control device controls alternating-current power of a first inverter unit so as to reduce the feed speed of at least one feed axis and controls alternating-current power of a second inverter unit so as not to limit torque of the spindle motor. Further, if it is predicted that the sum of the output of the servo motor and the output of the spindle motor exceeds power supplied by the rectifier unit, during an operation other than the cutting operation, the motor drive control device controls the alternating-current power of the second inverter unit so as to limit the torque so as not to reduce the feed speed.

Abstract: Methods of and a system for providing a visual representation of force information in a robotic surgical system. A real position of a surgical end effector is determined. A projected position of the surgical end effector if no force were applied against the end effector is also determined. Images representing the real and projected positions are output superimposed on a display. The offset between the two images provides a visual indication of a force applied to the end effector or to the kinematic chain that supports the end effector. In addition, tissue deformation information is determined and displayed.

Abstract: A control method for a power assist device provided with an operation handle, a force sensor that detects an operation force applied to the operation handle and an orientation of the operation force, a robot arm, and an actuator. When the orientation of the operation force is detected to be within a predetermined angle range with respect to a preset advancing direction of the operation handle, the actuator is controlled so as to move the operation handle along the advancing direction by employing only a component of the operation force along the advancing direction; and when the orientation of the operation force is detected to be outside the predetermined angle range, the actuator is controlled to move the operation handle by the operation force applied to the operation handle and the orientation of the operation force.

Abstract: Rotary encoders for use with trolling motors are disclosed. An example rotary encoder includes a housing defining an aperture and a linear guide and an input sleeve to extend through the aperture. The input sleeve includes an exterior guide to be engaged and followed by a shuttle to enable rotary position information to be obtained from the input sleeve. The shuttle is movably coupled within the linear guide. The shuttle is biased to engage a central portion of the exterior guide if rotation of the input sleeve moves the shuttle past first or second ends of the groove to prevent the rotary encoder from being damaged by over-rotation of the input sleeve.

Abstract: A motor control apparatus includes, a converter which converts input AC to DC for output, an inverter which converts the DC output of the converter to provide an AC output for driving a motor, and an inverter control part for controlling the same, and a numerical control part which outputs a motor operation command for commanding the operation of the motor, and wherein when AC current or power input to the converter lies outside a predetermined range, the inverter control part controls the AC output of the inverter so that the motor is operated in accordance with a limited torque command produced by limiting a torque command originally specified in the motor operation command.

Abstract: Disclosed are apparatus and methodology for providing a feedback mechanism to a system operator that provides a positive indication of the position of a valve which controls gas flow to a consumer. Rotation of a stepper motor controlling a valve mechanism is optically monitored and a feedback signal is sent to the system operator indicating positive operation of the valve only when a selected number of rotations of the stepper motor is reported. The stepper motor may be operated in different modes, each associated with different nominal current consumption levels. In a higher current consumption mode, such as a torque-oriented mode, the stepper motor may be stepped a few additional steps after valve closure to ensure seating of the valve.

Abstract: The present invention is aimed to realize a method and a system for controlling an electric cylinder by which the load detector that is attached to an electric cylinder and the rod of the cylinder can avoid being overloaded. An unexpected bump between the rod of the cylinder and the material to be pressed can cause that overload. A servo controller 17 determines whether the load for pressurizing Pm detected by the load detector 13 is larger than or equal to the load for detecting a bump Pc. If it is determined that the load for pressurizing Pm is larger than or equal to the load for detecting a bump Pc, the servo controller 17 determines whether the flag for stopping is ON. Also, the controller 17 determines whether the speed Sm of the rod 11 is greater than or equal to an allowable speed to bump Sc.

Abstract: Disclosed are a robot arm having high back-drivability to interact with a human being, which is safely stopped, and a method of controlling the robot arm. When the operation of the robot arm having high back-drivability to interact with a human being is converted into a safety mode due to the occurrence of an emergency, in which the operation of the robot arm is stopped, only a torque having a degree to compensate for gravity applied to the robot arm, i.e., only a torque to maintain the kinematical position of the current state of the robot arm without falling of the robot arm due to gravity, is outputted to control the robot arm as if the robot arm is in a weightless state, thus being capable of safely stopping the robot arm.

Abstract: A management apparatus is for managing a storage medium. The apparatus includes a rack including a cell which has a first opening and a second opening, a robot for inserting or ejecting the storage medium with respect to the cell through the first opening, and a controller for executing a process. The process includes driving the robot to start inserting or ejecting the storage medium with respect to the cell, detecting a failure in inserting or ejecting the storage medium, stopping the robot from inserting or ejecting the storage medium for a given time upon detecting the failure, and driving the robot to restart inserting or ejecting the storage medium with respect to the cell after the stopping the robot from inserting or ejecting the storage medium for the given time.

Abstract: A medical robotic system includes a surgical instrument, a robotic arm assembly, an input device, and a processor. The surgical instrument has an end effector and a sensor for sensing a force exerted by the end effector, and is operatively mounted on the robotic arm assembly. The processor is configured to receive commanded movement of the end effector from the input device, receive information of the force from the sensor, determine a reduced velocity of the commanded movement that would inhibit damage causing motion of the end effector, and control robotic manipulation of the surgical instrument in response to the commanded movement of the end effector while restricting the velocity of the commanded movement to the reduced velocity.

Abstract: An opening/closing control method for a window regulator, which is a method of performing opening/closing control with a pinching prevention function while determining a detection signal from a sensor based on a threshold value. The method includes setting the threshold value as a value offset from a reference value for control, and updating the reference value in correspondence to a value of the detection signal from the sensor in an initial stage of control, and each time when the value of the detection signal from the sensor continuously changes in a certain time within a range where the value of the detection signal from the sensor does not exceed the threshold value, the reference value is modified by a value corresponding to such a changed value.

Abstract: The mechanical differential actuator according to the present invention comprises a mechanical differential having three mechanicals ports. A first transducer with a low impedance is coupled to a first port, a second transducer with a high impedance is coupled to a second port, and the mechanical load is coupled to the third port. The mechanical differential actuator enables controlling a force and a speed at a load coupled thereto through a known relation between the force and the speed. Moreover, the mechanical differential actuator presents a compact structure enabling the transfer of a large force relative to its volume.

Abstract: A method is disclosed for automatically determining an effective mass of a door system that is driven by a motor and has at least one door. In this case a speed change accomplished during an acceleration movement is established, and a force variable, for example the motor current or an armature voltage, influencing the drive force of the motor is summed or integrated during the acceleration movement. The effective door mass is established from the sum or the integral of the force variable and the speed change, the summation or the integration of the force variable being performed over a number of operating system cycles of a control device assigned to the door system. Also described is a control device for automatically determining the effective door mass, having a memory for force variable profiles that is designed in such a way that mass can be established for different force variable profiles in the memory in conjunction with an unchanged program code.

Abstract: A control device for controlling a machine tool which can be used to drive tools includes a memory for storing a movement limit value which is respectively assigned to the tools and is specific to the respective tool. A desired value generating unit generates desired values for controlling the movement of the tool. The desired values are limited by a limiting unit on the basis of the assigned movement limit value in such a manner that the movement limit value is not exceeded when moving the tool.

Abstract: Methods, apparatus, and systems are disclosed for identifying force-ripple and/or side-forces in actuators used for moving a multiple-axis stage. The identified force-ripple and/or side-forces can be mapped, and maps of corresponding position-dependent compensation ratios useful for correcting same are obtained. The methods are especially useful for stages providing motion in at least one degree of freedom using multiple (redundant) actuators. In an exemplary method a stage member is displaced, using at least one selected actuator, multiple times over a set distance in the range of motion of the subject actuator(s). Each displacement has a predetermined trajectory and respective starting point in the range. For each displacement, respective section force-command(s) are extracted and normalized to a reference section force-command to define a section compensation-ratio.