Lloyd Johnson Dan Golding

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AIAA ATS 2006SVF Start Script19 May 2006

• Author Lloyd Johnson, Boeing
• Co-author Dan Golding, Cimarron (on Contract to
  Boeing)

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AIAA ATS 2006 - SVF Start Script

• The Software Verification Facility (SVF) is a key
  component of the Software Development Integration
  Laboratory (SDIL) located at the Sonny Carter
  Training Facility.

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AIAA ATS 2006 - SVF Start Script
The above figure is a closeup of the SVF portion
of the previous slide. This figure showcases many
of the features of the SVF. The terminals shown
in the above figure are from when the control
room was downstairs in the same room as the
equipment racks. The control room has since been
moved upstairs (away from the noise of the rack
cooling fans).
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SVF/ITR Architecture
AIAA ATS 2006 - SVF Start Script
RTIOP
RTIOP
Tier 1 MDM (CC)
1553
1553
1553
RTIOP
RTIOP
Tier 2 MDMs (INT, PMCU, GNC, PL, etc.)
1553
1553
ISS Simulations are hosted on RTIOPs (Real Time
Input Output Processors) The RTIOPs share data
with each other on a fiber optic reflective
memory ring. The simulations can be preconfigured
using cidinit files (initialization
files). Flight software items can be
preconfigured to a limited extent by loading PPLs
(PrePosition Loads) into EEPROM. To establish the
desired test configuration, commands are issued
from simulated MCC (Mission Control Center) or
simulated PCS (Portable Computer System).
RTIOP
RTIOP
1553
Tier 3 MDMs (PVCU, S0, S1, P1, N1, LA, etc.)
1553
1553
RTIOP
RTIOP
Fiber Optic Ring
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AIAA ATS 2006 - SVF Start Script
The displays shown are for the various
simulations and data monitoring equipment. Stage
Verification Tests are performed in the SVF
Control Room after the test configuration has
been established by running the SVF Start Script.
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AIAA ATS 2006 - SVF Start Script
The above diagram illustrates the Command Data
Handling Architecture of the ISS
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AIAA ATS 2006 - SVF Start Script
The CC (Command and Control) MDM
(Multiplexer/Demultiplexer) is key to configuring
flight elements to establish a test
configuration. All commands from the ground are
sent to CCS (Command Control Software) which
either executes the commands or routes them to
other flight elements The CES (CCS Environment
Simulation) includes a simulation of S-Band
equipment used by the ground to communicate with
the CCS. The CES also provides the user with the
ability to develop a C test script that is
compiled into a relocatable object module. At
run-time, the script processing capability of the
CES accepts requests from the operator to load
compiled test script object files and execute
them. A CES script is used to send commands to
CCS and receive telemetry from CCS via simulated
S-Band.
Simulated S-Band (within CES)
Commands
Telemetry
CC MDM
Commands
Telemetry
Other Flight Elements and Simulations
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AIAA ATS 2006 - SVF Start Script
During test execution, the PCS console is used
for commanding and verifying status. The PCS can
also be used by Test Operations personnel for
debugging and correcting start script execution
problems.
PCS Console
CES Console
In addition to monitoring the SVF Start Script,
and other scripts, the CES console is also used
for commanding CC via S-Band and monitoring
S-Band telemetry.
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AIAA ATS 2006 - SVF Start Script
Early SVF Start Scripts
Start

• From Assembly Flight 5A through 11A, the SVF
  Start Script performed relatively few functions
• Separate scripts were written to configure the
  GNC (Guidance Navigation and Control) system or
  the ECLSS (Environment Control Life Support
  System).
• As we started test development for ISS Assembly
  Flight 12A, the scripts were combined and
  additional functionality was added.
• It took approximately 1.5 hours to run the start
  script sometimes longer if problems were
  encountered.
• The script would pause and wait for operator
  intervention if problems were encountered.

Connect Simulated PCS
Activate Simulated S-Band
Power on lower Tier MDMs and command to
Operational
Activate Internal Thermal Control System (ITCS)
Report MDM Checksums and Exit
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AIAA ATS 2006 - SVF Start Script
In December of 2002, An Accelerated Improvement
Workshop (AIW) was conducted for the Lab
Operations Process. A Goal from the AIW was to
setup rig hardware and software such that
scheduled tests can start on time. Dan Golding
was a member of the AIW team. In February 2003,
Lloyd Johnson wrote a white paper proposing
methods in which the SVF Start Script could be
improved. Dan Golding implemented this approach
resulting in our current SVF Start Script.
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AIAA ATS 2006 - SVF Start Script
Previous Start Script Implementation
Proposed Start Script Concept
Start
Start
Perform Subsystem 1 Activation
Perform Subsystem 1 Activation
Perform Subsystem 2 Activation
Perform Subsystem 3 Activation
Perform Subsystem n Activation
Perform Subsystem 2 Activation
Perform Subsystem 3 Activation
Exit
The main concept embedded in the proposed SVF
Start Script improvement was to perform subsystem
activations in parallel.
Perform Subsystem n Activation
Exit
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AIAA ATS 2006 - SVF Start Script
Present Start Script Implementation
A while loop was used to implement parallel
subsystem activation. If the conditions were
established for subsystem activation, a function
call for the subsystem module would be
executed. Only a single command within the
subsystem activation would be issued provided the
conditions for this command have been met. The
function would exit after updating status
parameters to identify the state of the subsystem
activation module.
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AIAA ATS 2006 - SVF Start Script
A status structure was defined to track the
status of each module Content consists of Index
counter to indicate the next command to be
executed. Status of module execution Amount of
time to wait for telemetry Number of errors
encountered when telemetry is not received in
allocated time Total run time of module
Status Structure
struct stat_struct int indx /
each module's cmd index / int stat
/ each module's status / define START
1 / module has started / define INPROG
2 / in process / define WAIT 3
/ module is waiting for
telemetry confirmation / define PAUSED
4 / user intervention required /
define DONE 5 / module is finished /
unsigned int wait_time / wait counter in
seconds represents
time to wait for
desired telemetry state / int err
/ each module's error ctr / int time_min
/ each module's run time in min / int
time_sec / each module's run time in sec
/
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AIAA ATS 2006 - SVF Start Script

• The SVF Start Script currently consists of 18
  modules falling into 4 categories.
• 1. MDM Activation Powers on and configures
  Tier 2 MDMs INT, EXT, GNC, PM and PL.
• Subsystem Activation configures ECLSS, ECZ, PV,
  IATCS, EATCS, GNC, TRRJ, EEATCS, etc.
• PPL Loads loads PPLs into GNC, PL, CCS and PM
  to establish desired test configuration.
• 4. Other Miscellaneous activies not falling in
  the other categories

Module Definitions
/ define module ptrs in mod_stat / define
INT_MDM_MOD 0 define EXT_MDM_MOD
1 define GNC_MDM_MOD 2 define PM_MDM_MOD
3 define PL_MDM_MOD 4 define
ECLSS_MOD 5 define ECZ_MOD
6 define PV_MOD 7 define IATCS_MOD
8 define EATCS_MOD 9 define GNC_MOD
10 define OTHER_MOD 11 define
PM_PPLS_MOD 12 define CCS_PPLS_MOD
13 define SARJ_MOD 14 define
GNC_PPLS_MOD 15 define TRRJ_MOD
16 define EEATCS_MOD 17
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AIAA ATS 2006 - SVF Start Script
CES Simulation User Interface
Start Script execution status is displayed on the
CES SimUI (Simulation User Interface). As each
subsystem module function is called, the
subsystem is identified. The time of the function
call is identified. A brief description of what
the module is doing is reported. The SimUI data
is also stored in a log file.

• Metrics data from the log file can be extracted
  and used to support Process Based Management

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AIAA ATS 2006 - SVF Start Script

• In addition to the SimUI window, the UI Graphical
  Display will provide status of the start script
  execution.
• The UI Graphical Display (also called MADS for
  Monitor And Display System) provides continue
  buttons that can be clicked to force a paused
  module to resume execution.

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AIAA ATS 2006 - SVF Start Script
As shown below in the eclss_start_5.c script,
conditional compilation statements exist that
allow each module to be compiled as a standalone
script.
/ module list / include "int_mdm_start_6.c" in
clude "ext_mdm_start_5.c" include
"gnc_mdm_start_7.c" include "pm_mdm_start_6.c" i
nclude "pl_mdm_start_5.c" include
"eclss_start_11.c" include "ecz_start_10.c" incl
ude "pv_start_9.c" include "iatcs_start_5.c" inc
lude "eatcs_start_5.c" include
"gnc_start_8.c" include "other_start_4.c" includ
e "pm_ppls_7.c" include "ccs_ppls_5.c" include
"sarj_start_6_clean.c" include
"gnc_ppls_4.c" include "trrj_start_5.c" include
"eeatcs_start_4.c" include "12ato12a1_ppl_load.c"
/ Main Routine Begins Here / ifndef SCENARIO
/ SCENARIO defined in
main startup script / void
scenario(void) / Allows script to be
run standalone
/ struct stat_struct mod_statMOD_NUM
int i / General Loop Variable / /
Initialize Structure / for (i0iltMOD_NUMi)
mod_stati.indx0 mod_stati.statSTA
RT mod_stati.wait_time0
mod_stati.err0 mod_stati.time_min0
mod_stati.time_sec0 / end for /
eclss(mod_stat) endif
The modules that make up the SVF Start Script
module are contained in separate files and are
added to the main via include statements.
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AIAA ATS 2006 - SVF Start Script
Conclusions/Summary The SVF Start Script
multi-threaded design has reduced the start
script execution time by almost 80 percent (90
minutes to 20 minutes) providing more time for
test development and test execution The operator
interface provides clear status and will allow
the script to continue configuring other
subsystems even though a problem in a subsystem
has been encountered. Depending upon the test
objectives, the problem may have been encountered
in a subsystem that does not impact the test. The
logged data can be used for troubleshooting and
gathering metrics on problem occurrences and
execution time. The modular nature of this design
lends itself to modification as new flight
elements are introduced and existing flight
software and simulations are revised.