Topic ID: id_15460701
Version: 2.0
Date: Nov 8, 2018 1:36:23 AM

Gantry/Table Interference Test

1 Interference Test

1.1 Prerequisites

Be sure that the System State was restored from DVD per Restore System State.
Reset the hardware to download the new characterization values before performing the table/ gantry interference tests in this section.

1.2 Configuration

The table must:

Be flashed with latest software.
Have elevation, cradle, and IMS characterized.
Be mechanically aligned to gantry.
Have table/gantry characterization completed.
Have the table extender installed.

1.3 Test Outline

The following tests verify the proper tilt and table interference matrix on the gantry.

Table Elevation Tests,
Position Tilt: Move Table to Interference Limit,
Position Table: Move Tilt to Interference Limit,
Tilt Limits When Table Below Scan Plane Lower Limit,

1.4 Requirements

The following requirements are tested in this series of tests:

No motion causes the table to hit the gantry (or gantry to hit the table)
Requirement #1 includes the use of the table extender.
No tilt motion causes the gantry tilting frame to touch the stationary base covers for any tilt angle.

1.5 Limitations

These requirements are only met when the table is NOT in service mode.

1.6 Interpreting Test Results

If test results indicate that elevation and/or tilt display readings fail to meet specifications, DO NOT adjust the limit switches. Instead, re-characterize and/or adjust tilt speed. Perform elevation, cradle, and IMS first, then repeat the test. If it still fails, perform tilt.

2 Special Case Installations

Refer to the Installation Form, e4879.

3 Gantry Tilt Verification Test

3.1 Table Elevation Tests

Table 1. Table Elevation Tests
Test	Steps	Expected Results
1	Move the cradle (and IMS) to home position. Push the Table Down gantry push-button to lower the table to the minimum height.	Elevation Display should read 585.0 ± 3 mm
2	Raise the table to the maximum height using the gantry controls. If the mechanical alignment of the table/gantry is not correct, as is often the case during manufacturing staging, this value may be out of range. Most of the following tests are still valid: Those that might have some variation are indicated in bold type.	Elevation Display should read 25.0 ± 3 mm. If mechanical alignment of the table/gantry is not correct, this value can be as low as 0 mm and as high as 40 mm. Refer to Table Height Characterization in this manual.

3.2 Position Tilt, Move Table to Interference Limit

The following tests verify the table interference limits at different tilt locations.

note:

“S” means top of gantry tilts away from the table base.
“I” means top of gantry tilts toward the table base.

notice

For all tests, make sure there is 2.5 cm of clearance between the gantry and table. Also, for all tilt angles used in this test, make sure that the Gantry Tilting frame covers do not touch the stationary base covers.

Table 2. Position Tilt, Move Table to Interference Limit Tests
Test	Steps	Expected Results
1	Move cradle (and IMS) to home position and set internal landmark	Cradle position on the display should read 0.0.
2	Raise table height to maximum height. Set the internal landmark. Move the IMS into gantry 400 mm, as displayed on gantry. Set the internal landmark a second time. Move cradle into gantry 1 m.	Table elevation on the display should read 25.0 ± 3mm. (This value is the same as in the Table Elevation Test #2 in Table 1) Cradle position on display should read 1000.0 mm.
3	Tilt the gantry to I30.0. Lower the table until motion stops.	Table elevation on display should read 65 ± 3mm. Tilt display should read I30.
4	Tilt the gantry to I23. Lower the table until motion stops.	Table elevation on the display should read 124 ± 3mm. Tilt display should read I23.
5	Tilt the gantry to I20.0. Lower the table until motion stops.	Table elevation on the display should read 140 ± 3mm. Tilt display should read I20.
6	Raise the table elevation to maximum height.	Table elevation on the display should read 25.0 ± 3mm. (This value is the same as in Table Elevation Test #2 in Table 1)
7	Tilt the gantry to S30.0, then lower table until motion stops.	Table elevation on display should read 147 ± 3mm. Tilt display should read S30.
8	Tilt the gantry to S23.0. Lower the table until motion stops.	Table elevation on display should read 175 ± 3mm. Tilt display should read S23.
9	Tilt the gantry to S20.0. Lower the table until motion stops.	Table elevation on display should read 185 ± 3mm. Tilt display should read S20.
10	Raise the table to 145 mm.	Table elevation on display should read 145 mm. Tilt display should read S20.
11	Tilt the gantry to S30. Verify that the table height can be adjusted from 145 mm to 25 mm. (This value is the same as in the Table Elevation Test #2 Table 1)	Tilt display should read S30. The table lower limit should be 145 ± 3mm. Upper table limit should be 25 ± 3 mm. (This value is the same as in the Table Elevation Test #2 Table 1)
12	Set the table height to 63 mm.	Table elevation on display should read 63 mm.
13	Tilt the gantry to I30. Verify that the table height can be adjusted from 63 mm to 25 mm. (This value is the same as in Table Elevation Test #2 Table 1)	Tilt display should read I30. The table lower limit should be 63 ± 3 mm. The upper table limit should be 25 ± 3 mm. (This value is the same as in Table Elevation Test #2 Table 1)

3.3 Position Table, Move Tilt to Interference Limit

The following tests verify the tilt interference limits at different table heights.

note:

“I” means top of gantry tilts toward the table base
“S” means top of gantry tilts away from the table base.

notice

For all tests, make sure there is 2.5 cm of clearance between the gantry and table.

Table 3. Position Table, Move Tilt to Interference Limit Tests
Test	Steps	Expected Results
1	Move cradle (and IMS) to home position. Set internal landmark. Set gantry tilt to zero.	Cradle position on the display should read 0.0. Gantry tilt on the display should read 0.0.
2	Raise the table to maximum height. Set the internal landmark. Move the cradle into gantry 1 m.	Table elevation on the display should read 25.0 ± 3mm. (This value is the same as Table Elevation Test #2 in Table 1) Cradle position on the display should read 1000.0 mm.
3	Lower the table until height is 115 mm. Tilt the gantry top away from the table (“S”) until it stops.	Table elevation on the display should read 115 mm. The tilt display should read S30 ± 0.5º.
4	Tilt the gantry top toward the table (“I”) until it stops.	Table elevation on display should read 115 mm. Tilt display should read I24 ±0.5º.
5	Tilt the gantry to 0. Lower table until height is 200mm. Tilt the gantry top away from the table (“S”) until it stops.	Table elevation on display should read 200 mm. Tilt display should read S14.5 ± 0.5º.
6	Tilt the gantry top toward the table (“I”) until it stops.	Table elevation on display should read 200 mm. Tilt display should read I8 ± 0.5º.
7	Tilt the gantry to 0. Lower table until height is 210 mm. Tilt the gantry top away from the table (“S”) until it stops.	Table elevation on display should read 210 mm. Tilt display should read S10.5 ± 0.5º.
8	Tilt the gantry top toward the table (“I”) until it stops.	Table elevation on display should read 210 mm. Tilt display should read I6 ± 0.5º.

3.4 Tilt Limits When Table Below Scan Plane Lower Limit

The following tests verify the table and tilt interference limits when the table height is below the scan plane.

note:

“I” means top of gantry tilts toward the table base
“S” means top of gantry tilts away from the table base.

notice

For all tests, make sure there is 2.5 cm of clearance between the gantry and table.

Table 4. Tilt Limits When Table Below Scan Plane Lower Limit Tests
Test	Steps	Expected Results
1	Set the gantry tilt to zero. Move the cradle (and IMS) to the home position. Lower the table all the way. Set the internal landmark.	Cradle position on the display should read 0.0. Gantry tilt on the display should read 0.0. Table height should read 585 ± 3 mm. (This value is the offset from 560 mm by the same amount as the upper table limit varies from 25 mm in the Table Elevation Test #2 in Table 1)
2	Tilt the gantry forward and backward. Verify the following tilt limits: S0.5 & I30.	Gantry tilt on the display should read S0.5 ± 0.5º. Gantry tilt on the display should read I30.0 ± 0.5º.
3	Set the gantry tilt to 0. Using the gantry push-buttons, move the cradle in toward the gantry until it stops.	Gantry tilt on the display should read 0.0. Cradle should stop at 10.0 mm ± 6 mm from the home position. (This value is not valid if the table/gantry mechanical characterization is not correct as described in the Table Elevation Test #2 in Table 1. Ensure that the front of the table is at least 25 mm from the gantry.)
4	Set the gantry tilt to zero. Move the cradle to the home position.	Cradle position on the display should read 0.0 Gantry tilt on the display should read 0.0.
5	Raise the table to a height of 386 mm. Verify the following tilt limits: S11.0 & I30.0.	Table height should read 386 mm. Gantry tilt on the display should read S11.0 ± 0.5º. Gantry tilt on the display should read I30.0 ± 0.5º.
6	Set the gantry tilt to 0. Set the internal landmark. Using the gantry push-buttons, move the cradle (and IMS) in toward the gantry until it stops.	Gantry tilt on the display should read 0.0. The cradle should stop at 141 mm ± 6 mm from the home position.
7	Set the gantry tilt to zero. Move the cradle to the home position.	Cradle position on the display should read 0.0. Gantry tilt on the display should read 0.0.
8	Raise the table to a height of 242 mm. Verify the following tilt limits: S24.0 & I30.0.	Table height should read 242 mm. Gantry tilt on the display should read S24.0 ± 0.5º. Gantry tilt on the display should read I30.0 ± 0.5º.
9	Set the gantry tilt to 0. Raise the table to 210 mm. Using the gantry push-buttons, move the cradle in toward the gantry until it stops.	Gantry tilt on the display should read 0.0. The cradle should go all the way through the gantry bore to the full-extended position, (approximately 2445 mm for the GT 2000 table).
10	Set the gantry tilt to zero. Move the cradle (and IMS) to the home position. Lower the table all the way. Set the internal landmark.	Cradle position on the display should read 0.0. Gantry tilt on the display should read 0.0. Table height should read 586 ± 3 mm. (This value is the offset from 586 mm by the same amount as the upper table limit varies from 25 mm in the Table Elevation Test #2 Table 1)
11	Tilt the gantry top toward the table to a tilt of 30 degrees	Display should read I30.
12	With the table down all the way, move the cradle in until it stops.	The cradle position should be 378.5 ±3 mm.
13	Move the table to the home position. Raise the table to a height of 386 mm. Set the internal landmark. Move the cradle in until it stops.	Cradle position should be 403 ± 5 mm.
14	Raise the table to a height of 63 mm. Move the cradle in.	The cradle should go all the way through the gantry bore to the full-extended position, (approximately 2445 mm for the GT 2000 table).