High-precision linear stages used for applications such as surface measurement in life sciences, semiconductor manufacturing and other industries often require two distinctly different modes of motion. A rapid mode usually is needed to change locations quickly in the workspace, which might then be followed by very slow motion for finer focusing and resolution. The traditional option for achieving dual-speed motion has been to stack one stage atop another. But a promising new development controls dual-speed motion with a single-stage configuration. Watch this webinar to learn: –About both types of linear positioning system configurations –How to determine the extent to which they satisfy design requirements for velocity, range of motion and compactness

1. Developments In Precision
Positioning Stages with
High Speed Range

2. Before We Start
This webinar will be available afterwards at
designworldonline.com & email
Q&A at the end of the presentation
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3. Moderator
Presenter
Leslie Langnau
George Jaffe
Design World
Steinmeyer

4. Finding A Precision
Positioning Stage for
Applications with
Extremely Large
Velocity Range

5. “Dual-Speed”- Drive for Nanopositioning with Ball Screws
1.
2.
3.
4.
5.
Problem description
State of the art
New approach to the problem
Results of field tests
Some Applications

6. 1. Problem description – some typical requirements
for such a linear positioning stage
•
High dynamic velocity range (extremely slow to fast)
(Measurement, microelectronics, engineering,…)
•
High system accuracies for positioning - in sub-micrometer
range
•
Repeatability < 100 nm
•
Long travel - up to 300 mm and more

7. Another way to look at the issue . . .
Dr. Ing. h.c. F. Porsche AG
Speed from 1 km/h up to 300 km/h Speed from 0.05 mm/s up to 100 mm/s
Dynamic range = 3 x 102 : 1
Dynamic range = 2 x 103 : 1
But suppose the . . .
Requirement is 10 nm/s up to 100 mm/s
Dynamic range = 1 x 107 : 1 ! !

8. 2. State of the art – generally 3 possibilities
Advantages
Disadvantages
Ball screw /
DC-Motor/
Stepper motor
- horizontal and vertical application
- cost effective
- robust and tested principle
- low dynamic range
(1 : 2000)
Direct drives
- relatively cost effective
- very high accel and velocities possible
- no drive wear
- vertical usage critical (brake)
- heat generation
Piezo stack
- travels possible in submicrometer range
- very short travel ranges
- closed loop difficult
- position drift
- high voltage

9. 2. State of the art – or “if one stage doesn‘t work, use two!”
Combination of ball screw/motor-drive and piezo stacks
XYPiezo.stacksystem
XYBall.screwsystem
Mad City Labs
Inc.

10. 2. Stacked stages – what are the limitations of this approach?
•
•
•
•
•
2 stages = discontinuous position (variable performance)
due to series connection of drives -> low system stiffness
(low self frequency)
2 force generators / 2 measuring systems / 2 controllers
piezo mechanism is sensitive to shock and overload
high costs

11. 3. A New (and Patented) Approach to the Problem
Combination DC-Motor with ball screw drive/rotating piezo motor
DC-motor
Incremental measuring system
Ball screw
Rotational encoder
Rotating piezo-motor
Bellows coupling
Fixed bearing
Slide system
Support bearing
Permanent-electromagnetic coupling

12. 3.
A New Approach to the Problem Using a Rotary Piezo Motor

13. 3. A New Approach to the Problem
Characteristics of the rotary piezo motor

14. 3. A New Approach to the Problem – more details
Characteristics of the measuring system
- Scale resolution programmable from 5 μm-5 nm
- Accuracy 1 μm
- Interpolation error
< ± 0.12 μm over a
scale period of 20 μm

15. 3. A New Approach to the Problem – test set-up
Rotating piezo motor – Test assembly
Piezo motor

16. 4. First results of field tests – 10 µm steps
[nm]
10025
8020
6015
4010
2005
0
Positioning: 10µm steps

17. 4. First results of field tests – 1 µm steps
[nm]
1015
812
609
406
203
0
Positioning: 1µm steps

18. 4. First results of field tests – 50 nm steps
[nm]
65
52
39
26
13
0
-13
Positioning: 50nm steps

19. So, by way of review . . . “Dual Speed” stage
• We now have the possibility to move extremely slowly or
quite rapidly in a single stage with a common drive
element
• We are no longer limited to only very small movements in
small increments
• Now to some applications . . .

20. 5. Optical 3D Tool
e.g. Optical 3D measurement
Alicona Imaging - Graz

21. 5. Confocal Microscopy
• Coarse adjustment, focussing and scanning with
combined drive system possible
• Measuring range not limited to piezo stack range as
with this instrument 
Physik Instrumente (PI) GmbH & Co. KG.

22. Thanks for your attention!

23. Questions?
Design World
Leslie Langnau
llangnau@wtwhmedia.com
Phone: 440.234.4531
Twitter: @DW_RapidMfg
Steinmeyer
George Jaffe
gjaffe@steinmeyer.com
Phone: 781.273.6220

24. Thank You
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