2nd Supervisory BoardPackage 3.1 Summary

OUTLINEUniversity

Secondment

PACMAN alignment bench

25/09/2015by Iordan Doytchinov

University

2

1st year University review passed.

Advancing literature review for thesis. Topics in state of art literature reviewed:

PhD title: “Measurement Uncertainty Budget for future particle accelerators alignment bench”

- Standards for Uncertainty Evaluation, GUM, ISO, ASME as applied to various metrology systems

- Error budgets in precision machine design

- Uncertainty budgets in Metrology CT evaluation systems

- Uncertainty budgets in Articulated CMM arms Uncertainty Evaluation

- Uncertainty budgets in Task Specific CMM Uncertainty Evaluation,

The Virtual CMM’s

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- Current state of art in accelerator pre-alignment uncertainty budgets papers

Gap of knowledge

Secondment

3

2) Registration B to CExperiments

Clamp common fiducial

Requirements:U(A-B) <= 300 µm?

U(B-C) <= 100 µm at real time?

Fluoroscopy and CT

Surgical robot

Planned trajectory

Location on bone

A

C

1) Registration of location of A to B Experiment

B

1st June – 11th of September 3+ months

Secondment1st June – 11th of September 3+ months

- Reviewed relevant ISO, ASME and state of art

- Developed artefacts and measurement methods for uncertainty evaluation via the ‘substitution method’ of both arm and CT

- Written Monte Carlo Error based error budget MATLAB tool.

errorEncoders Q2 and Q3 = +- 3 arc minutes or +- 0.05deg (at Q mean = 280deg) (Gaussian distribution)errorEncoders Q4, Q5, Q6 = +- 6 arc minutes or +-0.1deg (at Q mean 60deg) (Gaussian distribution

Polar Coordinates future design error propagation of angle based Gaussian errors:

1 1.5 2 2.5 3 3.5 40.08

0.1

0.12

0.14

0.16

0.18

0.2

0.22

0.24Error PCT

1 1.5 2 2.5 3 3.5 4 4.5 5 5.5 60.2

0.22

0.24

0.26

0.28

0.3

0.32

Error PCT VS CMM Zehatz Fiducial

1 1.5 2 2.5 3 3.5 40

0.1

0.2

0.3

0.4

0.5

0.6

0.7Error CT

Error CT VS CMM Zehatz Fiducial Error PCT VS CMM Iordan Fiducial

+- 3 to +-6 arc minutes or +- 0.05deg Gaussian distribution angle Err.

STD Y = 0.3611mm

-0.0126 -0.0126 -0.0126 -0.0126 -0.0125 -0.0125 -0.01250

10

20

30

40

50

60Histogram of Gausion Error Distribution in Z

mm

PDE -200

0

200

-2000

200400

600

-200

-100

0

100

200

X [mm]

(43.2489,-266.7936, 711.2471)

Arm Kinematics Workspase

Z [mm]

Y [m

m]

5

PACMAN alignment bench

BPM axis determination

Wire

Sensor

𝑼 𝟏

𝑼 𝟐

𝑼 𝟑

𝑼 𝟒

GUM Supplement 1, 2008

ISO GPS part 2 Reproduction

Version 1 of Error sources completed by 2nd of October

To apply Virtual CMM and ‘substitution’ method with artefacts to study CMM Uncertainty (both with none contact and tactile sensor of CMM.

Highest error sources expected:- Thermal Issues- Magnetic influence- Uncertainties based on

methodology

To perform series of experiments in order to map the PDE distributions of the biggest contributors. To evaluate various measurement strategies expected uncertainty

Thank you for listening

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