motion Electronics Design Introduction motion control systems consist of three main components: motion controller, motor driver or amplifier, and a motion device. motion control systems consist of three main components: motion controller, motor driver or amplifier, and a motion device. The primary purpose of a motion controller is to control the dynamics of the motion device. The motor driver converts the command signals from the motion controller into power signals required to drive the motor. The motion device is any mechanical device that provides motion and is actuated by a motor. Such motion devices typically contain feedback devices to provide information such as position and velocity to the motion controller (see Figure 1). Each section is further explained below. motion controllers In a motion system, the motion controller is used to control motion devices such as stages and actuators so that they move or stop in a desired manner. If the motion system is equipped with position, velocity, or torque sensors, the signals from these sensors are fed to the controller. In servo systems, the controller compares the actual signal to a desired value and takes corrective actions. Common motion systems use three types of control methods: position control, velocity control, and torque control. Position control is used in applications where precise positioning and position tracking are of utmost importance. In these applications, the primary feedback device is an encoder. Velocity control is used in applications such as spindle, conveyor belts, and such where velocity regulation is of primary importance. In these applications, the primary feedback device is a tachometer. Torque control is used in applications such as robotics where the torque applied by end-effectors must be controlled accurately in order to grasp or release objects. In these applications, the primary feedback device is a torque/force sensor such as a strain gauge. A majority of Newports motion systems use the position control method. They use both encoder and tachometer feedback to attain high levels of positioning as well as velocity regulation. The purpose of the motion controller in these systems is to command a motor so that the actual position of the moving mechanism tracks the desired position specified by a preplanned trajectory. While the main objective of a motion controller is to control a motion device, many advanced motion controllers provide various additional functions such as: Trajectory generation for moving devices from one point to another or for coordinating the motion of multiple devices Interface to let users configure and command the motion system to perform various tasks Monitoring end-of-travel limits, amplifier faults, feedback errors, etc. for safety of the system Digital input/output lines to synchronize external events to motion or vice versa Memory for storing and running on-board motion programs Furthermore, the output of the motion controller can be configured depending upon the type of motor used to move a motion device. To control stepping motors, most motion controllers send two digital signals to the motor driver (amplifier). The driver must interpret these signals and provide appropriate commutation to rotate the stepping motor. These signals can be used in one of two ways: Step and Direction one signal is pulsed to command the driver to step the motor and the other indicates the desired direction of motion. Plus (CW) and Minus Pulses (CCW) one signal is pulsed to command the driver to step the motor in the positive direction, and the opposite signal is pulsed to command the driver to step the motor in the negative direction. A stepper motor control system does not require position feedback. The motion controller can simply provide the correct number of pulses to rotate the stepper motor the appropriate amount for a desired move. However, for improved positioning accuracy, a more sophisticated stepper motor system can also incorporate a feedback system (e.g., shaft-mounted rotary - or glass-scale linear -encoder) that can be used to directly monitor the position and provide the motion controller with actual displacement information. The motion controller can then provide a quasi-servo closed-loop positioning system that adds or subtracts output pulses to the driver to correct for positioning errors. For DC Servo motors, conventional motion controllers feed an analog voltage to the motor driver that varies from 10Vdc to +10Vdc. This command signal is often referred to as the DAC control signal. The motion controller adjusts the DAC output in order to make the actual position of the motion device accurately follow a desired position. (See Closed-Loop control section) To control servo motors in positioning applications, the motion device (i.e. stage) must provide some type of position feedback. A third mode used for brushless DC servo motors requires the motion controller to send two DAC control signals. These two sinusoidal signals are shifted 90° (or 120°) out of phase and used to directly commutate the motor. This method can also be used to commutate stepper motors, eliminating the need for complicated driver electronics. Motor Drivers A motor driver receives input signals from a controller and converts them to power to drive a motor. A motor driver can be a simple amplifier or it can be an intelligent device that can be configured through software for varying operation parameters. There are three classes of motor drivers available to support the different types of motors used in motion control. Stepper Motor Drives The stepper motor drive receives input signals from the motion controller commanding it to step the motor to a commanded position. The stepper motor drive then applies current to the stepper motor windings in order to move the stepping motor to the next step (increment). This basic operation is known as the Full Step operation of a stepper motor. In this mode, if power is removed from the motor, the stepper motor will not move significantly from its current position due to its inherent holding or detent torque. A more sophisticated stepper motor driver is capable of applying current to both windings of the stepper motor simultaneously. Proportioning the current of the two windings allows precise control of the position of the motor rotor between detent positions. Using this method known as Microstepping, the motor driver can divide the input step command by 1 to 1000 microsteps. This provides a much higher positioning resolution for stepping motors and minimizes resonance problems inherent to stepper motors over the speed range of the motion device. However, in this mode, if power is removed from the motor, the motor will move to its closest detent or full-step position. High-Voltage Chopper Technology A simple four-phase driver is suitable for basic, low performance applications. But, if high speeds are required, quickly switching the current with inductive loads becomes a problem. When voltage is applied to a winding, the current (and therefore, the torque) approaches its nominal value exponentially (Figure 2). When the pulse rate is fast, the current does not have time to reach the desired value before it is again turned off, so the total torque generated is only a fraction of nominal. The time required for the current to reach its nominal value depends on three factors: the motor windings' inductance, its resistance, and the voltage applied. The inductance cannot be reduced, but the voltage can be temporarily increased to bring the current to its desired level faster. The most widely used technique is a high voltage chopper. If, for instance, a stepper motor requiring only 3 V to reach the nominal current is connected momentarily to 30 V, it will reach the same current in only 1/10 the time. Once the desired current value is reached, a chopper circuit activates to keep the current close to the nominal value (Figure 3). DC Servo Motor Drives Drivers for DC Servo motors simply convert a 10Vdc to +10Vdc analog control signal from the motion controller to a usable current to drive the motor. DC Brushless Motor Drives Most brushless DC Motor drives are simple amplifiers that convert control signals from the motion controller to a usable current to drive the motor, with the motion controller providing the motor commutation. In some applications, however, the motor drive is an intelligent device that receives an analog input similar to the DC servo motor drive. In this case, the driver must have some internal microprocessing capability and requires feedback from the motor in order to commutate it. Brushless DC motor drives are available in three basic types. One type accepts a single analog 10 Vdc control signal (which represents either velocity or torque) from the motion controller and Hall effect signals from the motor, which is needed for commutation reference. Another type accepts two analog 10Vdc commutation signals from the controller and, therefore, does not require Hall signals from the motor. Lastly, there are intelligent drives that can self-commutate (generate its own sine and cosine commutation signals). These drivers are very flexible and can use the stages encoder feedback or Hall effect signals for motor commutation. Feedback Devices A feedback devices basic function is to transform a physical parameter into an electrical signal for use by a motion controller. Common feedback devices are encoders for position feedback, tachometers for velocity feedback, optical or mechanical switches for end-of-travel information, index signals for a fixed reference position, and hall effect sensors for brushless motor phase information, see Stage Components Considerations.

controller/Driver Selection Guide For stage and controller compatibility, Stage and controller Compatibility. For the NanoPZ controller, Ultra-High Resolution Actuator and controller

UTM Series Mid-Range Travel Steel Linear Stages The UTM Series linear stages feature an all-steel construction with preloaded linear ball bearing slides to provide high stiffness and thermal stability in a space-saving format. A large variety of DC, stepper, and manual drives, all available with different resolutions, allow selection of a stage that exactly meets your application. Smooth motion is provided by a diamond-corrected lead screw and a matched, precision lapped nut to ensure high position stability with high vertical load capacity. The nut design includes anti-backlash preloading and a sophisticated decoupling system that prevents lead screw eccentricity errors from affecting stage movement. All UTM stages include a center home position switch,supplemented by an index pulse signal from the encoder for precise origin location. The home position may also be set to either end of the stages travel via an external switch on the stage body. All-steel construction offers high stiffness and thermal stability with up to 150 mm travel range Multiple motor and feedback configurations allow exact matching to your application Backlash compensated lead screw with reduction gear provides 0.1 mm resolution with high position stability Vacuum compatible versions up to 10-6 Torr Stepper Drive Versions Stepper-motor-driven stages are offered in four variants: Two mini-step drive versions with resolutions of 1 mm (PP1HL) and 0.1 mm (PP.1). These combine high speed positioning and smooth displacement from 1/10-step per encoder count driving mode. For ultra-smooth low-speed positioning, micro-stepping up to 250x is possible using either the ESP300 or XPS motion controllers. Two full-step versions with resolutions of 1 mm (PE1) and 0.1 mm (PE.1). These are primarily designed for applications requiring the position to be maintained within the stages resolution when power is switched off, such as operation in vacuum. DC-Servo Drive Versions Four DC-motor-driven configurations are available: Two high-power DC-servo versions with resolutions of 1 mm (CC1HL) and 0.1 mm (CC.1). The CC1HL features a built-in tachometer to provide superior speed stability. Two low-power versions with resolutions of 1 mm (CC1DD) and 0.1 mm (CC.1DD). These stages offer a cost-effective performance alternative for those who have precision positioning needs with budget limitations. Design Details 1) Additional motor mounted gear on some drive options, see Stage Motor Technical Information Specifications 1) For a travel of 100 mm See the Metrology Tutorial section for more information on typical and guaranteed specifications motion controller Options For optimum performance and seamless compatibility, we recommend using one of the following motion controllers/Drivers: Assembly Pattern Stacking UTM Series stages either together or with other Newport stages is easily accomplished using optional Captive Screws (M-CAP-M41). Shown below are the assembly patterns used. These interfaces are accessed by removing the upper and lower plates of the stages. For assemblies requiring precise orthogonality (50 mrad), please consult our technical staff. Load Characteristics Ordering Information The UTM series of stages will be offered for a limited time only. Refer to the UTS series (see Mid-Travel Steel Linear Stages) of stages for comparable replacement units. Contact Newport Applications Engineers for special requirements. Dimensions

The RGV100BL is a very compact direct-drive rotation stage that provides ultra-fast rotation with very high resolution and outstanding positioning performance. Applications include semiconductor wafer inspection, micro-robotics, and precision metrology. The direct-drive technology of the RGV100BL eliminates the worm gear of traditional rotation stages. The advantages are higher speeds, superior reliability, and enhanced position sensitivity. Speed, resolution, and repeatability are increased by a factor of up to ten times compared to worm-driven rotation stages of the same size. A high efficiency brushless DC torque motor with rare earth magnets supplies an optimum ratio of torque per inertia for high acceleration, with minimal stage heating. At maximum continuous torque, the temperature of the motor increases by only 30°C. This is significantly less than other stage designs and guarantees high performance and high reliability for the most demanding applications. Precision is ensured by a high-resolution glass scale with 15,000 line pairs per revolution that directly measures the position of the rotating platen. The flat encoder is mounted on a precision ground reference surface and is perfectly aligned with the stages rotation axis to minimize position errors induced by eccentricity, wobble, or axial runout. The encoder signals are interpolated by the XPS motion controller with less than 0.1 arcsec resolution for outstanding position sensitivity and stability. The RGV100BL features a proprietary 4-point contact ball bearing. This unique, 2-piece design takes advantage of Newports excellent and proven capabilities in the design, manufacturing and assembly of precision mechanics and integrates multiple functions, like the bearing ways and the direct drive motor, minimizing the number of parts. The result is a more compact rotation stage with superior stiffness, high reliability and outstanding wobble and eccentricity specifications. A 30 mm diameter through-hole allows convenient routing of cables and vacuum lines through the stage. A once-per revolution index pulse permits precision homing to a unique home position. The RGV100BL also features two limit switches that can be enabled or disabled by an external switch.

HybrYXTM Single Plane XY Hybrid Air Bearing Stage Excellent price-to-performance value for demanding, high duty cycle industrial OEM applications. Ideal choice for scanning applications requiring ultra-low velocity ripple and dynamic following error. True single plane XY architecture with optional theta and Z-Tip-Tilt solutions. Extensive use of advanced ceramic materials provides lightweight, rigid, and a well damped structure. Large XY travel range (1 meter). Scanning velocity up to 600mm/sec and 0.6G acceleration. The all-new HybrYXTM single plane XY hybrid stage is the latest addition to Newports family of air bearing products offering the advantages of a single plane air bearing stage at a much lower cost than previously possible. The HybrYX stage is well suited for semiconductor wafer inspection systems and emerging maskless lithography applications. The stage is also an excellent choice for use in flat panel display (FPD) inspection and processing tools Innovative Architecture The HybrYX stage blends the cost advantage of mechanical bearings with the precision of a single plane air bearing carriage to deliver a powerful combination of throughput, precision and value. During motion, a ceramic carriage slides freely in X and Y on a precision lapped granite reference plane using a proprietary pressure-vacuum air bearing design. This carriage is guided along the Y-axis, using pressure-vacuum air bearings, by a rigid and lightweight ceramic beam. This ceramic beam is in turn supported at each end by recirculating ball bearing carriages and guided along the X-axis by linear rails. This results in a low-profile design that is extremely rigid, well-damped, and capable of quick & precise point-to-point moves and exceptional high-speed scanning performance. Linear Motor Drives Typically used as the stepping axis, the X-axis is driven by a pair of iron-core linear motors, one motor on each end of the ceramic beam. These linear motors were selected for their high efficiency and torque. To optimize scanning performance, an ironless linear motor drives the Y-axis through the CG of the single plane carriage. Performance without Compromise HybrYX was developed to overcome the disadvantages found in conventional stacked XY stage systems. Truck-and-rail based stages have limited performance capabilities, long-travel crossed roller bearing designs are hindered by large footprints and may not have adequate life-time or MTBF characteristics, and a pure, dual axis air bearing is often cost prohibitive. The unique hybrid architecture of HybrYX addresses all of these typical drawbacks and offers the following outstanding performance characteristics for demanding scanning applications: Z-jitter & dynamic straightness of less than 25nm during high speed motion Better than 0.1% Velocity ripple Compact 1200mm by 765mm footprint (with standard 650mm by 350mm travel range) Long-life & High MTBF (air bearing is not limited by bearing travel/life-expectancy) motion controller The XPS motion controller is recommended for optimized performance and ease of integration with the HybrYX stage. The XPS is a standalone motion controller in a 19in (4U) chassis capable of controlling and driving up to 8 axes of brushless linear/rotary, brushed-DC, and stepping motors. HybrYX utilizes three axes, leaving room for control of other motion devices. With all controller, interpolator, amplifier, and power supply components housed