Abstract: An apparatus, method and computer program product for: receiving information on a position of at least one user with respect to a spatial audio field provided by an audio source device, determining an audio volume level at the position of the at least one user, receiving information relating to background noise generated by the audio source device when providing the spatial audio field, determining, based on the audio volume level at the position of the at least one user and the information relating to the background noise, control information for controlling the audio source device, and controlling the audio source device based on the control information when providing the spatial audio field.

Abstract: Electric trolley includes safety controller that determines whether or not to stop the driving of driving wheel, and driving commander that outputs, to the motor driver, (i) an operation permission signal for permitting motor to be operated and (ii) a control signal for controlling an operation of motor, in which safety controller performs control to stop inputs of the operation permission signal and the control signal to motor driver when the safety controller determines to stop the driving of driving wheel.

Abstract: Provided are a motor control method and a device, applicable in the technical field of motor control, and particularly applicable to a controller in a motor control system. The system comprises one controller and at least two motors, and each of the motors drives one drive entity. The method comprises: acquiring a control instruction at a current time, a positional relationship of drive entities, and a system state after a previous program cycle has ended; on the basis of the acquired information, and in combination with a pre-established mapping of transition relationships and transition conditions between all system states, determining, from the control instruction at the current time, a target system state corresponding to the system state after the previous program cycle has ended, determining, according to the target system state, a target control instruction, and controlling actions of all of the motors.

Abstract: A converter, a first switch, a second switch, and an inverter are disposed in that order along a second direction, at a first position in a first direction. A reactor and a capacitor are disposed in that order along the second direction, at a second position in the first direction. Energy is stored in the reactor via the first switch. The capacitor is discharged via the second switch. At least one of a set of the reactor and the converter and a set of the capacitor and the inverter is disposed side by side along the first direction.

Abstract: A surgical instrument is disclosed. The instrument includes a microcontroller coupled to a memory, the microcontroller is configured to control the surgical instrument and a usage counter stored in the memory that is incremented when the surgical instrument is activated, wherein the microcontroller is further configured to prevent actuation of the surgical instrument when the usage counter is above a predetermined threshold.

Abstract: Surgical devices and methods are described herein that provide improved motor control and feedback, thereby combining advantages of manually-operated and powered surgical devices. In one embodiment, a surgical device includes a proximal handle portion that includes a motor, a distal end effector coupled to the handle portion, and a cutting element configured to cut tissue engaged by the end effector, wherein the motor is configured to supply power that moves the cutting element. The device also includes a motor control mechanism configured to cause the amount of the power to dynamically change in response to a manual user input when the cutting element is moving.

Abstract: An interior permanent magnet electric machine includes a stator having a plurality of teeth disposed around a circumference oriented radially towards a center defining slots interposed between each of the teeth, and a conductive winding wrapped around each of the teeth of the stator to receive an electrical current. The electric machine also includes a rotor which is rotatable relative to the stator. The rotor defines a plurality of openings to receive permanent magnets near an outer portion of the rotor and a number of spokes interposed between mass reduction cutouts located closer to the center relative to the permanent magnets. Each of the permanent magnets defines a magnetic pole and each of the spokes is circumferentially aligned with one of the magnetic poles.

Abstract: Various exemplary methods, systems, and devices for controlling a motor of a robotic surgical system are provided.

Abstract: A work vehicle has a running motor and includes a first controller generating a speed command value to control the motor and adding an actual running speed of the work vehicle to a relationship between a torque command value for a torque in the motor and a running speed of the work vehicle to generate a first torque command value and a second controller generating a second torque command value based on the speed command value and the actual running speed, controls the motor using a smaller one of the first and second torque command values when the work vehicle moves forward, and controls the motor using a greater one of them when the work vehicle moves backward. The first controller determines the speed command value based on an accelerator opening used to regulate the running speed, the actual running speed, and an actual movement direction of the work vehicle.

Abstract: The variable speed drive system is arranged to receive input power at fixed input voltage magnitude and frequency and provide power at a variable voltage and variable frequency. The variable speed drive includes a converter connected to an AC source to convert the input voltage to a boosted DC voltage. A DC link connected to the converter filters the DC voltage from the converter stage. An inverter converts the DC link voltage into variable voltage and the variable frequency AC power. An electromagnetic compatibility (EMC) filter includes a series RC circuit from phase-to-ground circuit for each input phase of the converter. The RC circuit includes a resistor connected in series with a capacitor between the converter phase and ground. The EMC filter is connected to the line side of the converter. An inductor is connected between the input source and the EMC filter.

Abstract: Surgical devices and methods are described herein that provide improved motor control and feedback, thereby combining advantages of manually-operated and powered surgical devices. In one embodiment, a surgical device includes a proximal handle portion that includes a motor, a distal end effector coupled to the handle portion, and a cutting element configured to cut tissue engaged by the end effector, wherein the motor is configured to supply power that moves the cutting element. The device also includes a motor control mechanism configured to cause the amount of the power to dynamically change in response to a manual user input when the cutting element is moving.

Abstract: A first motor controller generates commanded speeds of a first rotor of a first electric motor for a first time interval and a second time interval. A first speed monitor detects observed speeds of the first rotor for the time intervals. A first ratio is determined based on a relationship between respective commanded speeds and corresponding observed speeds for the first time interval and the second time interval. A first data processor increments a persistence counter for the first motor if the first ratio increases or changes during the time intervals. A first motor deceleration is estimated if the persistence counter exceeds a stall limit count. A target rotor speed of a second motor is adjusted based on the estimated first motor rate of change to track the first motor rate of change (or first rotor speed) if the persistence counter exceeds the stall limit count.

Abstract: A system, multiplexed controller, and a method of controlling a plurality of motors is described. The system includes a plurality of motors, at least two of the motors requiring a variable-frequency source or being a multi-speed motor. The multiplexed controller of the system is configured to control operation of the plurality of motors, the controller directly communicating with each of the plurality of motors.

Abstract: According to an embodiment of the invention, an apparatus is provided which includes a microprocessor, and a built-in temperature sensor configured to measure a temperature of the microprocessor as a reference temperature. The apparatus further includes external temperature sensors, where at least one of the external temperature sensors is configured to measure the temperature of the microprocessor. The microprocessor is configured to make an external temperature calibration using the reference temperature measured by the built-in temperature monitor. Each of the external temperature sensors is configured to monitor temperature information of a component and provide the temperature information to the microprocessor.

Abstract: A fan control system includes a first fan, a second fan adjacent to the first fan, a first motor that rotates the first fan, a second motor that rotates the second fan, and a control unit. The control unit controls the rotational speeds of the first motor and the second motor. The control unit decreases the rotational speed of the first motor and increases/decreases the rotational speed of the second motor when the rotational speed of the first motor must be decreased. The control unit can decrease the rotational speed of the second motor when the rotational speed of the first motor whose rotational speed has been decreased is lower than a prescribed rotational speed, and increase the rotational speed of the second motor when the rotational speed of the first motor whose rotational speed has been decreased is higher than the prescribed rotational speed.

Abstract: The invention relates to a drive apparatus (10) for the linear movement of a processing tool with respect to a workpiece, having a tool holder (18) which is fixed on a carriage (16) and is intended for the fastening of the processing tool, having a stationary guide device (12) in which the carriage (16) is guided such that it can be displaced in a vertically linear manner, and having a drive device (42) with a first force transmission means (46) which, in an engaged position, engages with a second force transmission means (40) connected to the carriage (16) in order to move the carriage (16). According to the invention, it is provided that the drive device (42) is mounted in the guide device (12) such that it can be moved between a release position, in which the force transmission means (40, 46) do not engage with one another, and the engaged position in such a way that the gravitational force of the drive device (42) causes a movement from the release position into the engaged position.

Abstract: A fan speed control circuit includes a first fan, a second fan, a first temperature sensor, a second temperature sensor, a PWM regulator, and a driving module. The first temperature sensor senses a temperature of the first component to generate a first temperature signal. The second temperature sensor senses a temperature of a second component to generate a second temperature signal. The PWM regulator is connected to the first temperature sensor and the second temperature sensor. The PWM regulator generates a first PWM signal according to the first temperature signal and generates a second PWM signal according to the second temperature signal. The driving module is connected to the PWM regulator. The driving module generates a first driving voltage provided to the first fan according to the first PWM signal. The driving module also generates a second driving voltage provided to the second fan according to the second PWM signal.

Abstract: According to an embodiment of the invention, an apparatus is provided which includes a microprocessor, and a built-in temperature sensor configured to measure a temperature of the microprocessor as a reference temperature. The apparatus further includes external temperature sensors, where at least one of the external temperature sensors is configured to measure the temperature of the microprocessor. The microprocessor is configured to make an external temperature calibration using the reference temperature measured by the built-in temperature monitor. Each of the external temperature sensors is configured to monitor temperature information of a component and provide the temperature information to the microprocessor.

Abstract: An HVAC/R system is configured with a variable frequency drive power supply which provides power to each of a compressor, a condenser fan, and a blower. In some embodiments, the compressor has a three-phase motor and the condenser fan has a single-phase motor.

Abstract: A system and method of spread-spectrum fan control for an air-cooled system is provided for reducing the vibrational and acoustical noise associated with the air-cooled system. The method includes generating a first control signal that controls a blade-passing frequency of a first cooling fan and a second control signal that controls a blade-passing frequency of a second cooling fan, wherein the first and second control signals may be pulse width modulated (“PWM”) signals. One or more noise generators independently vary duty cycles for the first and second PWM signals within a range around respective first and second blade-passing frequency set points. As a result, the blade-passing frequencies for the first and second cooling fans are independently and randomly modulated within a range around the respective first and second blade-passing frequency set points.

Abstract: A traction drive system comprising a plurality of electric motors selectably connected to a main shaft by engagement devices, each motor or combination of motors provides distinct performance characteristics along a broad spectrum of performance characteristics; and a method of managing a traction drive system including sensing physical parameters of the fraction drive system, selecting an electric motor having well-suited performance profile based on pre-selected criteria against which the sensed parameter is compared, and engaging one or more of the corresponding motors to the main shaft.

Abstract: A method of operating a motor is disclosed. The motor has a nameplate operating frequency and at least a first and second wiring configuration for operating at a first nameplate voltage and second, higher, nameplate voltage, respectively. The method includes operating the motor in the first configuration at a frequency and a voltage based on a set of frequency versus voltage ratios over a range of frequencies. A first ratio in a lower portion of the frequency range is lower than a second ratio in a middle portion of the frequency range. A third ratio in an upper portion of the frequency range is lower than the second ratio. The range of frequencies extends from a value below the nameplate frequency to a value above the nameplate frequency. The corresponding range of voltages extends from a value below the first nameplate voltage to a value above the first nameplate voltage.

Abstract: The present invention provides a motor drive system that is substantially more robust than those of the prior art. Generally, the motor drive system provides a redundant communication topology with the drives, thereby greatly reducing the chance of failure by a fault in the drive-to-drive communication link. Specifically, the motor drive system includes a plurality of motor drives joined by a communication media. Each motor drive has a motor control circuit configured to control the speed of an electric motor and a media access control unit having two communication modules. Each communications module includes a transmitter and a receiver joined to the communications media. A set of routing switches in the media access control unit joins the communication modules to connect the motor drives in an independent primary and a secondary ring communicating data for controlling the motor drives.

Abstract: An apparatus and method for servomotors of an electric injection molding machine includes a motion controlling unit, two driving amplifying units, and two servomotors respectively connected to the driving amplifying units. The motion controlling unit includes two servomotor position controllers both for receiving a first position command, and the driving amplifying units are respectively connected to the servomotor position controllers for receiving a second and third position command. Two position detectors are respectively received in the two screw caps that are mounted to the servomotors for detecting absolute positions of the corresponding screw caps. The screw caps are respectively connected to inputs of the first and second servomotor position controllers to form two screw cap position feedback circuits.

Abstract: The present invention discloses a system for realizing rotor variable frequency speed control asynchronously, which drives a plural of motors via one inverter. This system is consisted of a motor group, a rectifier group, a current limiter group, a chopper group, an isolator group, an active inverter, an A/D converter group, a signal processor group, a current detector group and a voltage detector group. By employing inversion control theory and CPU control technology, a plural of motors are controlled on line, the voltage output by one inverter is used as the additional inverse electromotive force of each motor, and each chopper is effectively turned on and turned off via a PWM signal which is output by each driver, so that four jobs of a crane, lifting, luffing, revolving and walking, can be realized. By the present invention, the circuit is simplified, the size is reduced, the cost is lowered, and the reliability is improved.

Abstract: Variable speed drives are utilized in refrigerant systems to operate motors of the system components at varying speeds, typically for the purposes of capacity adjustment, efficiency enhancement, reliability improvement or power consumption limitation. However, variable speed controls are expensive. The present invention offers flexibility to utilize a variable speed drive to provide variable speed functionality between compressor and fans (or other rotating components having electric motors) within a refrigerant system depending on operational and environmental conditions and external load demands. The switching device switches the variable speed drive between component motors as indicated by a control for the refrigerant system.

Abstract: A complex signal processing system for multiple fans is used to control the rotation of a first fan and a second fan. The speed signals of the first fan and the second fan are processed through an XOR operation to obtain a complex speed signal. In response to the complex speed signal, the speed and the operational status of the first fan and the second fan can be evaluated.

Abstract: A method of operating a vehicle at a substantially low speed based on change in the vehicle position. The method comprises the following steps: (A) transforming a steering control algorithm into a substantially low speed (SLS) steering control algorithm, wherein the (SLS) steering control algorithm is configured to operate the vehicle in an asynchronous low speed mode; and (B) implementing the SLS steering control algorithm as a controller configured to operate the vehicle in the asynchronous low speed mode.

Abstract: A capacity control algorithm for a multiple compressor liquid chiller system is provided wherein the speed and number of compressors in operation are controlled in order to obtain a leaving liquid temperature setpoint. In response to an increase in the load in the chiller system, the algorithm determines if a compressor should be started and adjusts the operating speed of all operating compressors when an additional compressor is started. In response to a decrease in the load in the chiller system with multiple compressors operating, the algorithm determines if a compressor should be de-energized and adjusts the operating speed of all remaining operating compressors when a compressor is de-energized.

Abstract: A method for controlling a first fan motor using a first pulse width modulation signal having a first pulse control factor, and for controlling a second fan motor using a second pulse width modulation signal having a second pulse control factor, so as to bring about an overall air output according to a prespecified setpoint air output by the operation of the first and the second fan motor, a low-pass filter being provided in parallel to the fan motors in order to smooth out voltage fluctuations in voltage supply lines, wherein the first and the second pulse control factor are made available independently of each other, in order to minimize the current through the low-pass filter.

Abstract: A fan motor drive control apparatus comprises a plurality of drive circuits for driving respectively a plurality of fan motors, and a speed change-over control circuit for transmitting a control signal for changing over speeds of the fan motors, to the plurality of the drive circuits, wherein each of the drive circuit comprises a stopping detection terminal for detecting stopping of a fan motor as an object to be driven, and the speed change-over control circuit transmits the control signal in accordance with a signal received from the stopping detection terminal.

Abstract: A dual fan module system 28 includes a two-speed electric motor 12 for operating a first fan 36, a one-speed electric motor 14 for operating a second fan 38, and switching structure K1, K2, K3, and K4 constructed and arranged to operate the system at more than two different speeds.

Abstract: This invention relates to a rotational speed control system including a plurality of motor drivers for driving motors, and the object thereof is to drive a plurality of motors at the same rotational speed without depending on the number of motor drivers and without depending on the characteristics of each motor driver. A remote controller 31 and a motor driver 202 are connected to a motor driver 201. The motor drivers 201 and 202 control motors M11 and M12 at a prescribed rotational speed, respectively. A rotational speed instructing signal 91 indicative of the rotational speed is supplied from the remote controller 31 to the motor driver 201, and further supplied from the motor driver 201 to the motor driver 202. Because the rotational speed instructing signal 91 indicates a rotational speed which is transmitted in a digital value between the motor drivers 201 and 202, both of the motors M11 and M12 are driven at the rotational speed indicated by the rotational speed instructing signal 91.

Abstract: A variable speed drive is provided having a converter to convert an AC voltage to a DC voltage, a DC link to filter and store energy from the converter, and a plurality of inverters, wherein each inverter is configured to convert a DC voltage to an AC voltage to power a corresponding load connected to the inverter The converter is electrically connected to an AC power source, the DC link is electrically connected to the converter, and the plurality of inverters are electrically connected in parallel to the DC link. Each inverter of the plurality of inverters is configured to operate substantially independently of other inverters of the plurality of inverters.

Abstract: A fan controlling system applicable in an electronic system having a plurality of fans is disclosed. The fan-controlling system includes a first signal generating module and a second signal generating module for generating a first and a second pulse width modulation (PWM) signals according to control instructions output by the electronic system. The fan-controlling system further includes a phase-inverting module and a delay module. Therefore, PWM signals, which are delayed with a time interval one another, can be generated by the fan controlling system, so as to respectively control a plurality of fans of the electronic system, thereby avoiding the peak value of the total power signals when the fans are run from increasing instantly, and power signal for supplying the electronic system from decreasing instantly, making the electronic system run abnormally, and its stability becomes worse.

Abstract: An electric vehicle in which left and right electric motors respectively driving left and right transporting parts are controlled by a control part and particular turning control of the electric motors is carried out when the electric vehicle turns. The electric vehicle has a left and right pair of push-button turn switches. When one of the turn switches is operated, the control part selects a pattern from multiple preset deceleration patterns and decelerates the motor on the inside of the turn, which corresponds to the turn switch being operated, on the basis of this deceleration pattern. The electric vehicle makes turns and returns to straight-line travel optimally and smoothly and can be operated easily by an operator with no skill or experience.

Abstract: To provide a power transmission device that can increase the range of speed variation between an engine and a power output shaft and effectively achieve reduction in size and cost of the device arrangement. The speed reduction ratios from an engine 1 to first output shaft 4c, 5c of first and second power distributors 4, 5 are different from each other. A speed change unit 10 is provided between the first output shaft 4c of the first power distributor 4 and a power output shaft 11 linked with driving wheels 2, 2 of the vehicle, and rotation transmission therebetween is achieved at a plurality of stages of speed reduction ratio. The rotation transmission from the first output shaft 5c of the second power distributor 5 to the power output shaft 11 is achieved via gears 20, 15b or rotation transmission mechanisms 15, 14 of a speed change unit 10 at a plurality of stages of speed reduction ratio.

Abstract: A dual motor configuration 10 is provided for driving two fans for moving air to cool an engine. The dual motor configuration includes a primary brushless motor 18 constructed and arranged to be electronically controlled to drive a first fan 16 over a range of speeds. A secondary brush motor 24 is constructed and arranged to be electronically controlled to drive a second fan 22 over a range of speeds. The secondary brush motor includes an electronic switching device 26 associated therewith for receiving a pulse width modulated signal for controlling speed of the secondary brush motor. Thus, different combinations of speeds of the first and second motors can be selectively chosen to meet cooling requirements.

Abstract: A cooling system includes multiple cooling fans, each driven by a corresponding fan motor controller. Each fan motor controller includes electronic commutation circuitry that is responsive to a modulated signal to control the speed of the associated motor and fan. The controller for one motor includes a microcontroller that receives a single control signal from an external control unit and translates that control signal into the modulated signals provided to all of the other motor controllers. In one embodiment, the microcontroller can adjust the duty cycle of the modulated control signals, and can stagger the on-off times of the signals to minimize conducted RFI emissions.

Abstract: A method (and apparatus) includes that a duty ratio of a driving voltage output to each wiper motor be required to be set according to several conditions. That is, while each wiper blade is moved in an interval from a starting position to a predetermined first wiping position in an upward operation, the duty ratio of a wiper motor on a driver's seat side is set so that the duty ratio is larger than the duty ratio of a wiper motor on a passenger seat side. Also, while each wiper blade is moved in another interval from each upper return position to a predetermined second wiping position in a return operation, the duty ratio of the wiper motor on the passenger seat side is set so that the duty ratio is larger than the duty ratio of the wiper motor on the driver's seat side.

Abstract: The invention concerns an improvement of a drive system of a color image forming apparatus. The color image-forming apparatus includes a plurality of image-forming elements; a plurality of first driving motors, each of which corresponds to each of the image-forming elements, to drive the plurality of image-forming elements; an intermediate transfer element that is disposed opposite the plurality of image-forming elements; a second driving motor to drive the intermediate transfer element; and a controlling section to control the plurality of first driving motors and the second driving motor. In the color image-forming apparatus, the controlling section controls the plurality of first driving motors and the second driving motor independently of each other, so that a first peripheral speed of each of the image-forming elements coincides with a second peripheral speed of the intermediate transfer element.

Abstract: A method for generating a compensated torque command signal to be applied to an electric power steering motor is disclosed. In an exemplary embodiment, the method includes generating an assist torque command signal responsive to a measured vehicle speed and an input steering torque signal. An assist dependent damping torque signal is generated, the assist dependent damping torque signal responsive to the assist torque command signal, the measured vehicle speed and a compensated motor velocity output value of the electric power steering motor. The assist dependent damping torque signal is then subtracted from the assist torque command signal.

Abstract: A control system controls the movement of an object based on desired position data. The control system includes a first regulator configured to regulate the position of the object, a feed forward control configured to feed the desired position data forward to a second regulator at a lower level than the first regulator, and a modeling filter configured to receive the desired position data and to provide the desired position data to the first regulator with a predetermined time delay.

Abstract: An answer system for technical support comprises an web server for receiving information of an inquiry sent from a user via an internet; an inquiry-information data base for storing the inquiry information which has been received by the web server; a fire wall for preventing the information of the inquiry, which is stored in the inquiry-information data base, from being accessed by outsiders via the telecommunication network; an intranet for communicating the information of the inquiry, which is stored by the web server, to an information service furnisher; an input unit for inputting an answer to the information of the inquiry, which has been communicated via the intranet; and a mail server for sending the answer to the information of the inquiry, which has been input by the input unit.

Abstract: A control system for an electric lift truck that controls a traction motor and a hydraulic pump motor is disclosed. The speed of rotation of both motors is controlled by a pulse width modulated current supplied from a battery source by the controller in direct response to a demand communicated to the controller through an interface manipulated by an operator. A pump driven by the pump motor supplies pressurized hydraulic fluid to a lift mechanism and a power assisted steering unit. A joystick with function switches mounted thereto is provided so that the operator steers with one hand while controlling truck propulsion and all functions of the lift mechanism with the other hand. The direct control of the pump motor speed enables a fully proportional control of the hydraulic system. The control system is a compact structure that requires minimal cabling and ensures that the hydraulic system operates with energy efficiency and minimal wear.

Abstract: A driving controller of electric vehicles. An angular accelerative dimension error calculator calculates error information having a dimension of angular acceleration of a car body. A feedback torque calculator calculates the feedback torque on the basis of the error information according to the sign of a steering angle and the error information, and ON/OFF of an accelerator. A vehicle controller corrects the reference torque, determined according to an accelerator angle and braking force, by the feedback torque, and outputs the corrected reference torque toward motor controllers, thereby improving vehicle running safety.

Abstract: A power output apparatus (20) of the present invention includes a clutch motor (30), an assist motor (40), and a controller (80) for controlling the clutch motor (30) and the assist motor (40). The clutch motor (30) includes an outer rotor (32) linked with a crankshaft (56) of a gasoline engine (50) and an inner rotor (34) connecting with a drive shaft (22). The assist motor (40) includes a rotor (42) connecting with the drive shaft (22). A control CPU (90) of the controller (80) controls a first driving circuit (91) to make the clutch motor (30) carry out power operation, so that the drive shaft (22) is rotated at a revolving speed higher than that of the crankshaft (56). The control CPU (90) also controls a second driving circuit (92) to make the assist motor (40) carry out regenerative operation. The electric power regenerated by the assist motor (40) is supplied to the clutch motor (30) to cover the electric power consumed by the clutch motor (30).

Abstract: A servo device which simultaneously controls plural servo systems, using a digital signal processor (DSP). The servo device includes plural servo systems, plural control subjects, and plural sensors which determine control quantities of the respective control subjects. The servo device also includes a calculation processing device which finds operating amounts of the respective control subjects from the control quantities which have been detected. The calculation processing device measures the gain of each servo system, and during the gain measurement of a given servo system, drops the control band of other servo systems, or sets the other servo systems to OFF or HOLD.

Abstract: An automated drafting system particularly suitable for drafting textile strands of sliver is provided. The automated drafting system includes a synchronous drive sliver drafting roller system utilizing toothed gears in the preferred embodiment operatively connecting a pair of drafting rollers with one of the rollers being directly driven by a motor to thereby cause identical rotation of both rollers. The automated drafting system also includes a system for securing and pressuring together upper and lower sliver drafting rollers wherein the lower roller of a pair of drafting rollers is preferably maintained in a fixed but rotational position while the upper roller of the pair is pressured towards the lower roller and controllably restricted as to both horizontal and vertical movement during the drafting process.

Abstract: A dual guide beam stage mechanism for accurate X-Y positioning for use e.g. in semiconductor processing equipment provides accurate planar motion and yaw control. Over-constraint between components in their relative motion is minimized by utilizing flexibly mounted air bearings at the connection between at least one of the moveable guide beams and its corresponding stationary guide, and between at least one of the guide beams and the adjacent stage itself. Thus stage yaw motion is provided by allowing yaw motion of one of the guide beams. Preloading provides enough constraint through the air bearings without over-constraining the moving components, thereby improving accuracy and also reducing the need for close manufacturing tolerances.