Nucletron Simulix-HQ User manual

Simulix-HQ
Technical Manual
REF 112.907ENG-00
NUC-T375-00

How to contact Nucletron Offices
NUC-T380-12
HOW TO CONTACT NUCLETRON OFFICES
Unless otherwise stated the service dispatch call number is the main telephone number.
Head Office and Manufacturer:
Nucletron B.V.
PO Box 930
3900 AX VEENENDAAL
Waardgelder 1
3905 TH VEENENDAAL
The Netherlands
Tel.: [phone]
Fax: [phone]
Service: [phone]
E-mail [email protected]
Web site: www.nucletron.com
BeNeLux
Nucletron B.V.
PO Box 930
3900 AX VEENENDAAL
Waardgelder 1
3905 TH VEENENDAAL
The Netherlands
Tel.: [phone]
Fax: [phone]
Service: [phone]
E-mail [email protected]
Web site: www.nucletron.com
Germany
Theranostic Medizintechnik GmbH
Obere Dammstrasse 8-10
D-42653 Solingen
Tel.: [phone]
Fax: [phone]
Service: [phone]
E-mail: [email protected]
Web site: www.theranostic.de
France
Nucletron S.A.R.L.
Parc d’Activités l. Bernard Vergnaud
15 rue Paul Langevin
93274 SEVRAN Cedex
Tel.: [phone]
Fax: [phone]
E-mail: [email protected]
Italy
Nuclital srl
Viale Elvezia no. 2
20052 MONZA (Milan)
Tel.: [phone] / 323148
Fax: [phone]
E-mail: [email protected]
United Kingdom
Nucletron UK Ltd.
Nucletron House
Chowley Oak
Tattenhall
CHESTER CH3 9EX
Tel.: [phone]
Fax: [phone]
E-mail: [email protected]
Sweden
Nucletron Scandinavia AB
Box 1704
Klostergatan 12
SE–751 47 Uppsala
Sweden
Tel: [phone]
Fax: [phone]
E-mail: [email protected]
Spain
Nucletron S.A.
Puerta de las Naciones
Calle Ribera del Loira, 46 Edificio 2
28042 MADRID
Tel. [phone]
Fax [phone]
E-mail: [email protected]
Europe / Middle East and Africa
Poland
Nucletron Poland Sp. z o. o.
Oddzial w Warszawie
Al. Krakowska 285
02-133 Warszawa
Poland
Tel.: [phone]
Fax: [phone]
E-mail: [email protected]

How to contact Nucletron Offices
NUC-T380-12
HOW TO CONTACT NUCLETRON OFFICES
Unless otherwise stated the service dispatch call number is the main telephone number.
USA
Nucletron Corporation
8671 Robert Fulton Drive
COLUMBIA, MD 21046
Tel.: [phone]
Fax: [phone]
E-mail: [email protected]
North and South
America
Canada
Nucletron Canada Inc.
411 Legget Drive, Suite 502
Kanata, Ontario
K2K 3C9
Canada
Tel: [phone]
Fax: [phone]
E-mail: [email protected]
Hong Kong
Nucletron Asia Pacific Ltd.
Room 1005, Tower 2, Silvercord,
30 Canton Road, Tsim Sha Tsui,
Kowloon, HONG KONG
Tel.: [phone] / 2684 / 3025
Fax: [phone]
E-mail: [email protected]
Australia
Nucletron Pty. Limited
Suite 4, 26 Sparkes Street
Camperdown. NSW. 2050
Sydney
Tel.: [phone]
Fax: [phone]
Email: [email protected]
China
Nucletron Asia Pacific Ltd.
Beijing Representative Office
Room 21D CITIC Building,
19 Jian Guo Men Wai Da Jie
Beijing, China
Post Code: 100004
Tel.: [phone] / 41
Fax: [phone]
E-mail: [email protected]
Web site: www.nucletron-china.com
India
Nucletron India Pvt Ltd.
No. 3, D’Silva Road
Mylapore
Chennai 600 004
Tel.: [phone]
Fax: [phone]
E-mail: [email protected]
Web site: www.nucletron-india.com
Nucletron Asia Pacific Ltd.
Shanghai Representative Office
Shanghai, China
Tel.: [phone] / 48
Fax: [phone]
E-mail: [email protected]
Web site: www.nucletron-china.com
Asia Pacific
Singapore
Nucletron Asia Pacific Ltd.
Singapore Representative Office
89 Science Park Drive
Rutherford # 03 - 06
Singapore 118261
Tel.: [phone]
Fax: [phone]
E-mail: [email protected]
Your Distributor / Agent

Preface
NUC-T374-02 v
Preface
Identification
Manuals are identified by a part number. The part number consists of three
parts:
Example:
The part number is printed on the right bottom side of the front page.
Numbers printed on other pages are for internal revision control and may
differ.
CE Classification
Manuals made for products that have been CE (Conformité Européenne)
marked have the CE mark on the front page. The number behind the CE
Mark defines the responsible notified body.
Nucletron systems are classified according to IEC 601-1 as Class I, type B.
Nucletron systems meet the relevant provisions of the European Medical
Device Directive 93/42/EEC or the European Active Implantable Medical
Device Directive 90/385/EEC; this is based on conformity of the products
and the quality system according to ISO 9001:2000 and ISO 13485:2003.
For this reason mark is used.

Preface
vi NUC-T374-02
Directive WEEE
Symbol Meaning Remarks
Location: Near or on
the type identification
plate.
Symbol for separated collection of
electrical and electronic equipment per
Directive 2002/96 of the European
Parliament and the Council of the
European Union (Directive on Waste of
Electrical and Electronic Equipment). If
applicable to the type of device, it
indicates legally imposed obligations
within EU member states, Iceland,
Norway and Switzerland when the
equipment is disposed of, at the end of
its life-time.
Owners of marked equipment should
contact the organization that imported
the equipment into their country, when
they want to dispose of the equipment,
at the end of its lifetime. The Directive
prioritizes re-use of equipment over re-
use of components over re-use of
materials over disposal as waste. Article
5 part 2d allows producers to decline the
return of any used equipment that is or
may be biologically or radiologically
contaminated.
Conventions
Throughout this manual certain conventions are used. These are Warnings,
Cautions and Notes. They provide a means of prioritizing information to be
brought to the attention of the user. They are given as follows:
Warning: Designates a possibly dangerous situation. Non-observance may lead
to death or the most severe injuries
Caution: Designates a possibly harmful situation. Non-observance may lead to
minor injuries or damage to the product.
Note: Designates a possibly harmful situation. Non-observance may lead to
damage to the product or the environment.
Precautions
The user is expected to use the product (soft and hardware) in accordance
with the instructions given in this manual, which must be read before the
system is used. Any unauthorized deviation from the procedures laid down
in this manual can affect the contractual obligations between purchaser and
vendor.
Warning: Do not modify any part of Nucletron supplied computer's hardware,
software or software configuration. Installing or running an appli-
cation that has not explicitly been approved by Nucletron may
compromise patient safety and will result in termination of all
warranty and service contracts.

Preface
NUC-T374-02 vii
Warning: The Nucletron products are designed for use and maintenance using
only parts available from Nucletron. No liability for failure can be
accepted by Nucletron through the use of parts obtained from other
suppliers unless written permission is obtained from Nucletron.
Copyright
All rights reserved. No part of this manual may be reproduced or transmitted
in any form whatsoever, including photocopying and recording without
written permission of the copyright holder: Nucletron B.V., PO Box 930,
3900 AX VEENENDAAL, The Netherlands.
Concerning this Publication
Information contained in this publication is subject to change without
notice. Whenever the equipment is delivered with a documentation medium
such as a CD or DVD, the user shall always check the medium for latest
information. This information is part of Release Notes and Document
Upgrade files.
Neither Nucletron B.V. and its subsidiaries nor anyone else who has been
involved with the development, production or delivery of the documentation
be liable for any special, incidental or consequential damages, whether
based upon breach of warranty, breach of contract, negligence, strict
liability in tort or any other legal theory.

Preface
viii NUC-T374-02

Table of Contents
112.907ENG-00 Simulix-HQ – Technical Manual ix
Table of Contents
1. Introduction 1-1
1.1 Intended Audience ............................................................................................................. 1-1
1.2 Related Documents............................................................................................................ 1-1
1.3 About This Manual ............................................................................................................. 1-1
1.4 Glossary of Terms.............................................................................................................. 1-2
1.5 Co-ordinate Conventions.................................................................................................... 1-2
2. System Overview 2-1
2.1 General............................................................................................................................... 2-1
2.2 System Architecture ........................................................................................................... 2-1
2.3 Central Cabinet................................................................................................................... 2-2
2.4 Basic Computer System..................................................................................................... 2-2
2.5 User Interface..................................................................................................................... 2-3
2.6 Service Panel ..................................................................................................................... 2-3
2.7 Safety System .................................................................................................................... 2-3
2.7.1 Hard Collision Detection ..................................................................................... 2-4
2.7.2 Computer Failure Detection................................................................................ 2-4
2.7.3 Mains Power Failure Detection........................................................................... 2-5
2.7.4 Power Supply Failure Detection.......................................................................... 2-5
2.7.5 Position Transducer Failure Detection................................................................ 2-5
2.7.6 Control Panel Failure Detection.......................................................................... 2-5
2.7.7 Relay Failure Detection....................................................................................... 2-5
2.7.8 Enable Bars......................................................................................................... 2-5
2.7.9 Brakes Normally On............................................................................................ 2-5
2.7.10 Unintended Movement Protection....................................................................... 2-6
2.8 Micro-Processor Output Interface ...................................................................................... 2-6
2.8.1 DC Motor Control Boards.................................................................................... 2-7
2.8.2 Relay Board ........................................................................................................ 2-7
2.8.3 Signal Conversion Boards .................................................................................. 2-7
2.9 Micro Processor Input Interface ......................................................................................... 2-7
2.10 Externals and Options........................................................................................................ 2-8
2.10.1 Collimator Light................................................................................................... 2-8
2.10.2 Optical FSD meter (ODI)..................................................................................... 2-8
2.10.3 Room Lights........................................................................................................ 2-8
2.10.4 Iso-Centre Locators ............................................................................................ 2-8
3. Installation 3-1
3.1 Overview............................................................................................................................. 3-1
3.2 Installing the Floor Interface............................................................................................... 3-1
3.3 Installing the Central Cabinet............................................................................................. 3-1
3.4 Installing the Gantry ...........................................................................................................3-2

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x Simulix-HQ – Technical Manual 112.907ENG-00
3.5 Installing the Pedestal Table.............................................................................................. 3-2
3.6 Mounting the Collimator ..................................................................................................... 3-2
3.7 Mounting the Image Intensifier System.............................................................................. 3-2
3.8 Mounting the Cassette Holder............................................................................................ 3-2
3.9 Installing the X-ray System................................................................................................. 3-2
3.10 Externals and Options........................................................................................................ 3-2
3.11 Service Control Box (Service Panel).................................................................................. 3-3
3.12 Service Override Button ..................................................................................................... 3-3
4. Adjustments and Calibrations 4-1
4.1 Configuration...................................................................................................................... 4-2
4.1.1 User Set Up......................................................................................................... 4-3
4.1.1.1 Screen Layout.................................................................................... 4-5
4.1.1.2 Movement Names.............................................................................. 4-8
4.1.1.3 Treatment Machine Parameters........................................................ 4-9
4.1.1.4 Fixed Treatment Field Names ......................................................... 4-13
4.1.1.5 User Preferences............................................................................. 4-14
4.1.1.6 Patient ON/OFF Load...................................................................... 4-16
4.1.1.7 Printer Set Up .................................................................................. 4-17
4.1.1.8 Length of Name/ID........................................................................... 4-31
4.1.2 Hardware Set Up............................................................................................... 4-32
4.1.2.1 Dimensions...................................................................................... 4-33
4.1.2.2 Image Intensifier Configuration........................................................ 4-34
4.1.2.3 Gantry/II Arm Configuration............................................................. 4-38
4.1.2.4 Collimator and Yoke Configuration.................................................. 4-39
4.1.2.5 Wireless Control Keys ..................................................................... 4-41
4.1.2.6 Hardware Options............................................................................ 4-48
4.1.2.7 Service Representative.................................................................... 4-49
4.1.2.8 Table Configuration ......................................................................... 4-50
4.1.3 Options.............................................................................................................. 4-51
4.1.3.1 Verification System.......................................................................... 4-52
4.1.3.2 Tomo Adapter.................................................................................. 4-56
4.1.4 EEPROM Maintenance..................................................................................... 4-60
4.1.4.1 Error Overview................................................................................. 4-62
4.1.4.2 Default Setting ................................................................................. 4-63
4.1.4.3 Error Correction ............................................................................... 4-65
4.2 Mechanical Iso-Centre Adjustments................................................................................. 4-68
4.2.1 Collimator Adjustments..................................................................................... 4-68
4.2.1.1 Cross-Wire Centring ........................................................................ 4-68
4.2.1.2 Field Illumination Pinhole Lateral Position....................................... 4-68
4.2.2 Collimator Axis Alignment................................................................................. 4-68
4.2.2.1 Axis Parallelism................................................................................ 4-69
4.2.2.2 Axis Co-incidence............................................................................ 4-69
4.2.3 X-ray Tube Alignment ....................................................................................... 4-70
4.2.3.1 Focal Height..................................................................................... 4-70
4.2.3.2 Field Co-incidence........................................................................... 4-70
4.2.4 Field Magnification Equivalence ....................................................................... 4-71
4.2.5 Optical FSD Meter (ODI)................................................................................... 4-71

Table of Contents
112.907ENG-00 Simulix-HQ – Technical Manual xi
4.2.6 Mechanical FSD Meter ..................................................................................... 4-71
4.3 Calibration of Movements................................................................................................. 4-72
4.3.1 The Software End Stops................................................................................... 4-72
4.3.2 Potentiometer Wiring Check............................................................................. 4-74
4.3.3 Gantry Calibration............................................................................................. 4-75
4.3.3.1 C-Arm Rotation................................................................................ 4-75
4.3.3.2 FAD Movement................................................................................ 4-76
4.3.3.3 AFD Movement................................................................................ 4-77
4.3.3.4 II-X and II-Y Movements.................................................................. 4-77
4.3.4 Table Calibration............................................................................................... 4-78
4.3.4.1 Table Height..................................................................................... 4-78
4.3.4.2 Table Iso-centric Rotation................................................................ 4-79
4.3.4.3 Table Eccentric Rotation.................................................................. 4-79
4.3.4.4 Table Lateral and Longitudinal ........................................................ 4-80
4.3.4.5 Table Speed..................................................................................... 4-80
4.3.5 Collimator Calibration........................................................................................ 4-80
4.3.5.1 Collimator Rotation .......................................................................... 4-81
4.3.5.2 Field Wires....................................................................................... 4-81
4.3.5.3 Collimator Shutters .......................................................................... 4-82
4.3.5.4 Shadow Tray Calibration ................................................................. 4-83
4.4 DC Motor Drives............................................................................................................... 4-85
4.4.1 Adjustments To Be Done At Installation or Replacement................................. 4-85
4.4.2 Factory Adjustments, Part 1.............................................................................. 4-85
4.4.3 Adjustment of Movement Velocity..................................................................... 4-85
4.4.4 Adjustment of Offset ......................................................................................... 4-86
4.4.5 Adjustment of I-Imp........................................................................................... 4-86
4.4.6 Adjustment of I-eff (sometimes called I-nom) ................................................... 4-87
4.4.7 Adjustments To Be Done At Installation or Replacement................................. 4-88
4.4.8 Factory Adjustments, Part 2.............................................................................. 4-89
5. System Checks 5-1
5.1 Settings Check List.............................................................................................................5-1
5.2 Movement Ranges ............................................................................................................. 5-1
5.3 Collision Avoidance Checklist ............................................................................................ 5-2
6. Preventive Maintenance 6-1
7. Troubleshooting 7-1
7.1 Service Screens .................................................................................................................7-1
7.2 Error Handling .................................................................................................................... 7-9

Table of Contents
xii Simulix-HQ – Technical Manual 112.907ENG-00
8. System Block Diagram 8-1
9. Functional Diagrams 9-1
10. Signals Lists 10-1
10.1 Introduction....................................................................................................................... 10-1
10.2 Signal Lists....................................................................................................................... 10-1
10.3 Name Conventions........................................................................................................... 10-1
10.4 Abbreviations.................................................................................................................... 10-1
10.5 Signal List – Sorted By “Location”.................................................................................... 10-3
10.6 Signal List – Sorted By “Name”...................................................................................... 10-11
11. Jumpers, Indicators and Fuses 11-1
11.1 Jumpers............................................................................................................................ 11-1
11.2 LED Indicators................................................................................................................ 11-44
11.3 Fuses................................................................................................................................ 11-1
12. Illustrated Parts Catalogue 12-1
12.1 Spare Parts List................................................................................................................12-1
12.2 System Interconnection Cables...................................................................................... 12-70
13. Additional Information 13-1

Introduction
112.907ENG-00 Simulix-HQ – Technical Manual 1-1
1. Introduction
1.1 Intended Audience
This manual is intended for service engineers involved in maintenance and repair of the Simulix-HQ
radiotherapy simulator system.
1.2 Related Documents
Publications related to this manual are listed in the following table:
Title REF Number
Simulix-HQ Operator’s Manual 112.900ENG
Simulix-HQ Acceptance Protocol (Section 1) 112.901ENG
Simulix-HQ Acceptance Protocol (Section 2) 112.456ENG
Simulix-HQ Installation Manual 112.902ENG
Simulix-HQ Site Preparation Manual 112.903ENG
Simulix-HQ Service Manual 112.904ENG
Simulix-HQ Concrete Mould Installation Instructions 112.906ENG
Simulix-HQ Log Book 112.908ENG
1.3 About This Manual
The Simulix-HQ consists of the following major parts:
• The gantry and the pedestal table with local control panels.
• The remote control console.
• The central cabinet with system electronics.
Various auxiliary equipment can be added; some of this equipment is described in this manual.
Note
If this manual does not provide all the information required for a specific type of auxiliary equipment, contact
the local Nucletron service organisation for details.
The system overview chapter provides an overall introduction of the Simulix-HQ system.
The installation chapter is a short description of the steps for a complete Simulix-HQ installation. For more
details, please refer to the Simulix-HQ Installation Manual, the Simulix-HQ Site Preparation Manual and the
Simulix-HQ Concrete Mould Installation Instructions.
This manual also provides the following information:
• Methods for adjustments and calibrations.
• How to check the functioning of the system.
• A troubleshooting assistance using the extensive error handling support of the Simulix software.
• A reference for fault finding in the electronics, for which the complete functional diagrams are enclosed.

Introduction
1-2 Simulix-HQ – Technical Manual 112.907ENG-00
The complex information about the electronics is organized in such a way that occurring errors can be
pinpointed efficiently. A system block diagram followed by the complete functional diagrams of the
electronics give insight in the working of the Simulix-HQ system.
Various reference tables are included for the electronic signals on connectors, pins, signal names, etc. The
tables also link the signals to the functional diagrams.
An overview of all jumpers, indicators and fuses is included.
Parts can be located with the illustrated parts catalogue.
1.4 Glossary of Terms
FAD Focus to Axis Distance: distance between X-ray tube focus and iso-centre.
AFD Axis to Film Distance: distance between iso-centre and film plane.
FSD Focus to Skin Distance: distance between the X-ray focus and a user-definable plane out of the
axis, usually the skin of the patient.
TAD Tabletop to Axis Distance: distance between tabletop and iso-centre.
FFD Focus to Film Distance: the sum of AFD and FAD.
IIX Image Intensifier (or film cassette) X-direction
IIY Image Intensifier (or film cassette) Y-direction
1.5 Co-ordinate Conventions
Iso-centric axis definitions:
Longitudinal The horizontal axis around which the gantry rotates.
Vertical The vertical axis around which the iso-centric rotation of table takes place.
Iso-centre Intersection of the longitudinal and vertical iso-centric axes. X, Y, Z co-ordinates are (0,0,0).
XThe lateral direction, i.e. in a horizontal plane and perpendicular to the longitudinal iso-
centric axis. When standing in front of the gantry, the X(+) direction is from the iso-centre to
the right.
YThe longitudinal direction, i.e. in a horizontal plane and parallel to the longitudinal iso-centric
axis. When standing in front of the gantry, the Y(+) direction is from the iso-centre towards
the gantry, away from the observer.
ZThe vertical direction, Z(+) is upwards.
CW Clockwise rotation, indicated as a (+) positive direction of rotation:
Longitudinal axis: right-hand rotation when standing in front of the gantry
Vertical axis: table iso-centric rotation, right-hand looking top-down (from the ceiling).
Collimator rotation, right-hand looking bottom-up (from the floor).
CCW Counter-clockwise.

System Overview
112.907ENG-00 Simulix-HQ – Technical Manual 2-1
2. System Overview
2.1 General
The Simulix-HQ is designed to simulate the functions of radiotherapy treatment machines.
The system consists of a pedestal patient table and a C-arm gantry with an X-ray source (tube) and on the
opposite side an imaging system (image intensifier with TV camera). The imaging system displays a
fluoroscopic, real-time X-ray image of the patient. A cassette holder is mounted on the image intensifier to
enable the insertion of a film cassette for X-ray photography.
The co-ordinates and angles of the Simulix-HQ are measured relative to the so-called iso-centre, the
intersection of the (imaginary) gantry rotation axis and the X-ray beam.
Various radiotherapeutical treatments can be simulated by observing the X-ray beam through the patient with
the gantry rotated under certain angles and the table in different lateral, longitudinal and height positions
relative to the iso-centre. Furthermore the image intensifier can be moved in a perpendicular plane to the X-
ray beam (X and Y direction).
To simulate different treatment machines the X-ray tube (focus) can be moved to and from the iso-centre,
thus varying the focus-axis distance (FAD). Also the image intensifier can be moved to and from the iso-
centre, changing the axis-film distance (AFD).
The Simulix-HQ has the possibility to perform combined movements of gantry, table and image intensifier to
reach pre-set positions and set-ups.
Limitation of the X-ray field is possible through adjustment of lead shutters in the collimator placed between
the X-ray source and the patient. Adjustable field delineating wires and fixed cross wires assist the operator
in optimising the X-ray field set up. A field light projector in the collimator visualises the set-up of the shutters,
the delineating wires and the cross wires on the skin of the patient, before actual X-ray radiation is applied.
The focus skin distance can be measured with a projector type optical distance indicator mounted on the
collimator.
During simulation the Simulix-HQ offers the controls for room lights to be dimmed or switched on-off and
laser iso-centre locators to be switched on off.
Optionally a computer tomography system (Simulix, CT Extension) may be added.
2.2 System Architecture
Technically speaking the Simulix-HQ provides the operator with the possibility of motorised movement of the
various system parts to the correct position and set-up required for the application.
The main system components are:
• Central cabinet with the system electronics.
• A microprocessor basic computer system.
• A user interface by means of dedicated control panels, an infrared hand held remote control (optional), a
keyboard, data monitor, and printer.
• A service panel.
• A safety system.
• Microprocessor output interface electronics to the actuators (motors).
• Microprocessor input interface to determine the actual positions of system parts (position potentiometers
or micro switches).
• Support of externals and options.

System Overview
2-2 Simulix-HQ – Technical Manual 112.907ENG-00
2.3 Central Cabinet
The central cabinet is a freestanding metal cabinet containing the system electronics such as
microprocessor, signal processing, motor control, power control, safety circuits etc.
The electronic hardware is mounted on three panels inside the cabinet:
• The upper panel comprises a computer rack and a connector for the service engineer control panel.
• The middle panel contains the motor control hardware and transformer and rectifiers for the DC-motors.
• The lower panel contains power supplies, mains power input circuitry and transformers, a fuse panel, the
hard-wired touch guard anti-collision provision and some electronics to control miscellaneous externals
like room-lights and room-lasers.
Power and signal cables are routed from the central cabinet to the gantry, the pedestal table and the control
panels.
2.4 Basic Computer System
The Simulix-HQ central control system consists of a 68020-based microprocessor, built around a
GESPAC-standard bus. It comprises four standard modules and a dedicated VDU board.
These modules are:
• The processor module (GESMPU-20).
• A general-purpose I/O module (GESCIO-1B).
• Two TTL I/O modules (GESPIA-2A).
• Interfaces to the control panels, the colour data monitor and, optionally, a third monochrome or colour
data monitor interface.
The processor module, together with the VDU board, a +5VDC power regulator and a data monitor, form a
minimal operational system. The processor module is a printed circuit board with the CPU, 256 kB of static
RAM memory and a set of four ROM's.
The general-purpose I/O module consists of a set of 16 input and 16 output channels, all opto-coupled.
Through a pair of flat cables the I/O module is coupled to a relay board.
Each TTL I/O module has 40 programmable input or output lines on two ports. The modules are connected
to signal conversion boards through flat cables.
The VDU board has all the supporting hardware for proper functioning of the CPU:
• The VDU interface; each VDU is connected via a signal conversion board which sits piggyback on the
VDU board.
• The configuration EEPROM, the language EPROM and the firmware.
• Three RS422 serial interfaces for communication with the consoles.
• An RS232 serial line interface (SLI, for service).
• A +/- 12V-voltage converter for the RS232 serial line interface.
• A real-time clock (RTC).
• The interface to the service control box.
• A set of status LED's.
After powering up the system with the mains switch on the remote control panel, the Simulix software
performs a start-up sequence including a software system check.
The system presents itself to the user via the connected VDU in the so-called user mode.

System Overview
112.907ENG-00 Simulix-HQ – Technical Manual 2-3
2.5 User Interface
Three dedicated control panels are the primary user interface for the Simulix-HQ operator:
• The remote control panel is designed for use on a desk in an operator's room, next to the X-ray shielded
area of the simulator. The panel has two pieces, a console containing the joysticks and push buttons and
a so-called miscellaneous box with the electronics and connectors. Typically, the miscellaneous box is
mounted under the desk.
• On each side of the pedestal table a local control panel is mounted. These panels provide a limited (as
referred to the remote control panel) number of simulator controls.
Optionally, an infrared control system can be installed consisting of a handheld unit and a receiver box,
which is typically mounted on top of the central cabinet.
Entering of patient data and system set-ups can be done through an alphanumeric keyboard. Through the
user interface the operator commands the Simulix-HQ software to perform certain functions. The effect of
these commands can be observed by the actual movement of parts of the Simulix-HQ and by looking at the
displayed information on the data monitor.
If required, information about the patient and Simulix-HQ treatment set-up can be printed.
2.6 Service Panel
This panel becomes active in the service mode and is also used during installation.
• To enter the service mode, press the CH SCR button on the service panel.
WARNING:
Only qualified service personnel is allowed to operate the Simulix-HQ via the service panel.
WARNING:
In service mode the service panel directly actuates system movements (motors) through the
software without taking software anti-collision pre-cautions into account.
Note:
Hardware movement end switches are always operational.
2.7 Safety System
The Simulix-HQ system is equipped with an elaborate safety system to protect the patient on the table, and
the simulator hardware against operator mistakes and hardware errors. The safety system comprises:
• Hard collision detection.
• Soft collision detection.
• Computer failure detection.
• Mains power failure detection.
• Power supply failure detection.
• Position transducer failure detection.
• Control panel failure detection.
• Relay failure detection.
• Emergency control panel.
• Enable bars on control panels (dead man button principle).
• Brakes normally on.
• Unintended movement protection.

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2-4 Simulix-HQ – Technical Manual 112.907ENG-00
2.7.1 Hard Collision Detection
The hard collision detection system prevents the collimator and image intensifier assemblies from running
into the table or into the patient on the table. The detection system consists of a set of switches, wired in
series. The switches are activated by the collimator touch bar and the spring-mounted film cassette holder.
If one of the collision detection switches is activated, then all table and gantry motions will be arrested.
The operator can override the arrest on the table motions by depressing the 'override' push button on the
control panel when the push button is lit (it depends on the gantry angle, which table motion is possible).
Also the outward movement of the collimator and image intensifier can be activated in the same manner.
The soft collision detection system is implemented in the computer program that controls the movements of
the simulator. The program keeps track of the positions of the collimator, the image intensifier and the patient
table and takes appropriate action when any of these approach such obstacles as the floor, the ceiling, or
each other too closely.
WARNING:
The anti-collision system can only avoid collisions with known, fixed objects in the room and only if
it has been programmed (configured at installation time) to do so.
Each moving part of the machine is considered to be surrounded by three concentric invasion zones, the
outer zone, the middle zone and the inner zone.
• If the outer zone is invaded, the operator is allowed to press the 'override' push button to continue the
motion.
• If the middle zone is invaded while executing pre-sets, then the offending motions are arrested; the
'override' push button lights and a message is displayed on the data screen, alerting the operator. The
motion can be continued by depressing the 'activate pre-sets' and 'override' push buttons; and pushing
the control lever that corresponds to the offending motion, all at the same time.
WARNING:
Moving any Simulix component in 'override' mode may result in an actual collision.
• The inner zone approaches the machine parts very closely, and serves as a protection zone against
erroneous input of pre-set values. If the operator attempts to enter a pre-set that would lead to an
invasion of the inner zone, then the entered value will be rejected.
Note:
To avoid collisions between the table and parts of the gantry, table and gantry rotational motions are only
allowed when the table is locked in its normal position (no eccentric tabletop rotation).
2.7.2 Computer Failure Detection
When power is switched on to the Simulix-HQ system, the computer executes a sequence of functional tests
to ascertain that all power supply voltages are present and that the system control hardware, including the
computer itself, functions correctly.
If the basic computer system does not contain a fatal error, then an error message will be displayed on the
data screen if an error is found somewhere in the control system. A fatal computer failure is indicated by the
CPU status LED's on the VDU board.
The computer system is supervised by a pair of watchdog timers. Each watchdog timer contains a relay,
wired in series with the emergency stop switches.
At power-up, each watchdog timer is tested and if found functional, activated by a signal from the processor;
the timer then closes its relay. However, after approximately 150 milliseconds, if nothing more happens, the
watchdog will time out. If all is well, the processor will prevent the timeout by sending a new activation signal
every 50 milliseconds.
If the processor is defective, (e.g. due to a memory fault or power supply failure); or unable to execute its
program properly, it will not be able to re-activate the timer.
If the processor fails to reset a watch dog timer, the watchdog relay opens. The emergency stop circuit
opens, causing the motor power control relays to switch the motor drive power off.

System Overview
112.907ENG-00 Simulix-HQ – Technical Manual 2-5
The state of the watch dog timers is indicated by means of a LED.
2.7.3 Mains Power Failure Detection
The Simulix-HQ control system will shut down in orderly fashion when the mains power sags or fails. Motor
drive power will be switched off by the safety relays and the processor resets.
When mains power returns, the processor will execute a full start-up cycle, including power-on testing.
2.7.4 Power Supply Failure Detection
The DC power supplies are directly monitored by the processor. Loss of DC power will be detected by the
processor and the data monitor will display an error message.
2.7.5 Position Transducer Failure Detection
The positions of the various moving parts in the simulator are recorded by means of wire wound precision
potentiometers. Since the potentiometer readouts constitute the only information that the control system has
on the whereabouts of the moving parts of the simulator and the information is used in the anti-collision
algorithms, a potentiometer failure must be detected as soon as it occurs.
The low end of each potentiometer is always connected to 0 VDC, the high end to the 10 VDC reference
supply.
However, the whole travel range of the potentiometers is never used. Therefore a hard 0 V or 10 V readout
on a potentiometer indicates a fault in the circuit (defective potentiometer, broken wire, short circuit).
If the control computer detects a defective potentiometer circuit the data monitor will display an error
message.
2.7.6 Control Panel Failure Detection
The Simulix-HQ control desks are self-contained, processor-controlled units that communicate with the
central control system through a serial communication link. Only the Emergency Stop, Drive Power On,
Override switches and Enable bars are hard wired into the central cabinet.
The communication link is always active, even when no commands are issued from the control panel. If a
control panel fails to respond correctly to signals from the central control system, an error message will be
displayed on the data screen.
2.7.7 Relay Failure Detection
All circuits that control motor drive power are provided with a mechanical safety relay circuit or relays in
series, monitored by the processor for correct operation.
The safety relays are constructed in such a way that if one contact pair should become stuck together, the
other contacts become inoperative.
The relays are always used in pairs, their contacts are wired together so that they close a circuit only if the
relays are both on or both off. If this circuit is inserted in series with the relay coils, then the relays can be
activated only if they are both fully operational. Alternatively, the interlock circuit may be monitored by
another safety device: if the circuit is open, then one of the relays is known to be defective.
2.7.8 Enable Bars
No part of the simulator will move unless the operator actively presses the enable bar on the control panel
and simultaneously takes positive action to actuate a movement control (a push button, joystick or executing
presets). Motion will stop as soon as the operator releases the enable bar (dead man principle).
2.7.9 Brakes Normally On
The brakes of the motors require electrical release power.
So before movement can take place the software must give release power to the motor brakes.

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2-6 Simulix-HQ – Technical Manual 112.907ENG-00
2.7.10Unintended Movement Protection
The software continuously monitors the position of the following movements:
• Gantry Rotation
• FAD
• AFD
• XRII Lateral
• XRII Longitudinal
• Collimator Rotation
• Table Vertical
• Table Lateral
• Table Longitudinal
• Table Iso-centric Rotation
When one of these parts moves while the software has not issued a movement command, the Drive Power
will be deactivated (by deactivating the two watchdog relays). This will stop all movements.
The unintended movement protection software operates at all times that the Drive Power is on. This feature
may be demonstrated as follows:
1) Switch on the Simulix and Drive Power.
2) Introduce an unintended movement as follows
• Actuate relay K133 manually.
The Image intensifier will move a short distance to the right
The Drive Power will automatically be deactivated, all movements will stop and blue error screen
appears
3) To clear this error, follow the instructions of the screen, that is:
• Press F5 to clear the error screen
• Press “Drive Power” to re-establish drive power
WARNING:
After an “unintended movement” error, do not switch on the Drive Power with a patient on the table.
The movement that caused the error may still be defect and may start moving when the drive power
is re-established. Although the unintended movement protection will deactivate Drive Power again
when it detects the unintended movement, the distance to the patient will become shorten.
When during an emergency off load while the power is still on, the Simulix-HQ table is lowered, two error
messages may appear:
a) An unexpected movement error from the table vertical drive software.
b) An unexpected movement error from the global unintended movement protection.
Special provisions have been made to make sure that no error messages will appear during calibration. At
the same time, the “unexpected movement error” that may appear when performing the calibration for Table
Vertical, Gantry Rotation, FAD or AFD is also suppressed.
2.8 Micro-Processor Output Interface
The software translates all user wanted movement commands into motor control commands which must be
interfaced from the computer to the physical machine.
All kinds of AC and DC voltages and currents have to be generated for different kinds of resistive and
inductive loads.