Precision Linear Motorized Stages

1
Precision Linear Motorized Stages

• Proteep Mallik
• OPTI 521 Tutorial Presentation
• December 4, 2006

2
Precision Linear Motorized Stages

• Long travel (2m)
• High precision (nm level)
• Stepper drives
• Parker Motion products

3
Outline

• Motion Control
• what, where and why?
• System Components
• stage (long range)
• motor (servo vs stepper)
• controller
• computer/software
• Examples
• vendors
• specifications
• cost

• Parker Motion System
• Linear sliders and stages
• 6K controller
• Computer monitor
• Null test system
• Conclusions

4
Motion Control

• Precise positioning of optics and mechanics
• Used in
• laser machining, welding
• printing, patterning
• wafer fabrication, lithography
• robotics
• and of course, in many optical systems

5
Motion Control

• Why motorized?
• repeatable, precise and smooth
• moving heavy parts
• automation
• easy to manage complex systems
• less manpower

6
System Components -overall system
ROTARY BRAKE
SHAFT BRAKE
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System Components -stage

• Range of travel ( 2m)
• Precision ( nm)
• Repeatability ( sub nm)
• Stiffness (extruded Al, excellent)
• Motor requirements (torque, efficiency)
• Cost (5000)
• Ease of operation (cabling, computer control)
• Mount on large, flat surface (minimum deflection)

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System Components -motor

• Servo
• Ironcore, ironless, slotless
• Typical repeatability 1nm, resolution 0.01nm
• Needs position encoders
• Very smooth, fast motion for large loads
• AC or DC, high voltage
• Expensive (5000 )
• Stepper
• Multi-pole motors
• N-bit encoders (2N bits/step)
• Repeatability 10nm, resolution sub nm
• No need for position encoder
• Easier maintenance and lower cost than servo

9
System Components -controllers

• Interfaces user to linear stage
• via computer or remote control
• Drive, encoder, limit and communication inputs
• Programmable

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System Components -computer

• RS-232 or ethernet communication
• Software from manufacturer
• Programming via Active X or other windows
  platforms
• Industrial computers, touchscreen control monitors

11
Vendors

• Parker Automation (Parker Hannifin, Daedal
  Positioning, Compumotor)
• Aerotech
• Velmex
• Newmark

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Specifications
13
Parker Automation
www.parkermotion.com
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Parker Automation

• Workstations
• Ethernet communication with controllers
• Controllers can be used in client-server modes
• Controllers can be connected to each other via
  ethernet hub
• Touchscreen monitors

15
Null Test System
3-axis stage
Tilt stage
CGH positioning stage
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Null Test System

• 5A drivers/motors
• 20A, 120V AC input power

17
Conclusions

• Precision motion control a reality and necessity
• 3 choices to make stage, motor, controller
• Complete automation via computer and available
  software