ADMET ppt

1

Study of Accuracy of a Long-Travel-Range, Ultra-High-Resolution, Hybrid-Drive Translational Stage using Laser

Interferometer

BySamik Dutta, Somnath Chatterjee, Ranjan Sen

CMERI Durgapur

Objective1. Performance evaluation of individual stage

movements of meso-micro-nano machine tools in the micro and nano scale range.

2. Linear and angular errors of state-of-the-art hybrid drive translational stage has been examined by laser interferometer.

3. To exploit full potentials of scanning probe microscope to take nano scale measurement of 3D surface topography, high precision nano positioning stage are essential for testing.

Experimental Set-up1. Smart table (vibration isolation table) UT2 with ST-200

controller of Newport corporation with IQ damping technology.

• Working Surface: 400 Series ferromagnetic stainless steel 3/16 in. (4.8 mm) thick with integrated damping layer

• Surface Flatness : ±0.1 mm over 600 mm2

• Core Design : Trussed honeycomb, vertically bonded closed cell construction.

• Maximum dynamic deflection coefficient: 0.4 × 10-3

• Maximum relative motion value : <7.6 × 10-8mm• Deflection under load : <1.3 × 10-3mm

Experimental Set-up contd…2. Translational stage, M511.HD, PI made:• C-702 controller• Hybrid drive consisting of a motor and piezo

actuator with a servo control mechanism • Guiding mechanism: ball screw • Linear optical encoder resolution: 2nm • Minimum incremental motion : 4nm • Accuracy < 0.05 µm• Hysteresis : 0.01 µm• Pitch, Yaw: ± 25 (5.15) µrad (arcsec)

Experimental Set-up contd…3. Reference scale: LASER interferometer• LASER source: He-Ne laser (λ=632nm)• Accuracy : 1 part in 107 which is 10 nm in 100 mm • Working principle: Michelson laser interferometerTemperature of experiment: 20±0.5°C

6

Measurement of Length Michelson Interferometer

L

LIntensity

Output sinusoidal

with a phase lp=q L4

For λ = 632.8 nm and for a length L = 1m

No. of oscillations = 1580278.13

Using modern detectors it is possible to measure 1 to 1000 parts of one oscillation

Resolution in this case is 0.3164 nm

Experimental Set-up contd…

Reading

Temperature sensor

M-511.HD

Mirror & beamsplitter

Laser source

C-702

Experimental Set-up contd…

Laser source

Mirror & beamsplitter

Translational Stage

Reading

Angular Measurements

Result Com

position (mm)

True position

(forward) (mm)

Error (f) (µm)

True position (backward) (mm)

Error (b)

(µm)

Hysteresis (µm)

0 0 0 0 0 05 5.0001 -0.1 5.0006 -0.6 0.5

10 10.0003 -0.3 10.0006 -0.6 0.315 15.0005 -0.5 15.0004 -0.4 0.120 20.0005 -0.5 20.0005 -0.5 025 25.0005 -0.5 25.0008 -0.8 0.330 30.0006 -0.6 30.0007 -0.7 0.135 35.0005 -0.5 35.0005 -0.5 040 40.0011 -1.1 40.0005 -0.5 0.645 45.0015 -1.5 45.0006 -0.6 0.950 50.0016 -1.6 50.0011 -1.1 0.555 55.0019 -1.9 55.0012 -1.2 0.760 60.0021 -2.1 60.002 -2 0.165 65.003 -3 65.0023 -2.3 0.770 70.0029 -2.9 70.0021 -2.1 0.875 75.0027 -2.7 75.0022 -2.2 0.580 80.0026 -2.6 80.0024 -2.4 0.285 85.003 -3 85.0018 -1.8 1.290 90.0023 -2.3 90.0019 -1.9 0.495 95.0016 -1.6 95.0014 -1.4 0.2

100 100.0011 -1.1 100.0011 -1.1 0

Result contd…

-10 0 10 20 30 40 50 60 70 80 90 100 110

-3.0

-2.5

-2.0

-1.5

-1.0

-0.5

0.0

0.5

1.0

1.5

Par

amet

ers(

mic

ron

)

Commanded Position(mm)

ErrorF ErrorB Hysteresis

Result contd…CommandPosition (mm)

Yaw (F) (arcsec)

Yaw (B) (arcsec)

Pitch (F) (arcsec)

Pitch (B) (arcsec)

0 0 0 0 0

10 2.94 1.42 3.5 2.55

20 2.2 0.57 6.24 5.15

30 2.49 1.54 7.63 7.15

40 2.22 1.07 9.55 9.88

50 3.05 1.93 11.81 12.6

60 2.31 2.66 15.28 14.72

70 2.39 1.46 17.26 16.35

80 0.08 -0.45 19.26 17.6

90 -3.34 -3.91 19.28 19.1

100 -5.58 -5.58 19.53 19.53

Result contd…

-10 0 10 20 30 40 50 60 70 80 90 100 110

-2

0

2

4

6

8

10

12

14

16

18

20

22

Pit

ch e

rro

r(ar

csec

on

d)

Commanded Position(mm)

PitchF PitchB

-10 0 10 20 30 40 50 60 70 80 90 100 110-7

-6

-5

-4

-3

-2

-1

0

1

2

3

4

Yaw

err

or(

arcs

eco

nd

)Commanded Position(mm)

YawF YawB

Conclusions

• To get the best performance, there is a definite ratio between incremental step and velocity.

• Future work can be done to get the best ratio using design of experiment.

• There is some problem of linear positioning between 65mm to 85mm. It may be due to errors in guide mechanism.

Thank You