Finite State Machines (FSM) in Control Systems: getting started

1
Finite State Machines (FSM) in Control Systems
getting started

• Why FSM? Partitioning, hierarchy and automation
• The method
• A given example
• Practical instructions
• Conclusions

2
Why FSM?

• To reduce the number of parameters exported and
  managed in the supervisory layer
• To give a certain level of automation at complex
  Detector Control System
• to integrate in the ALICE DCS the sub-detector
  C.S. with related hierarchy and partitioning
  features.

3
Automation benefits
For the LHC detectors with thousands of HV LV
channels, gas , cooling, trigger, DAQ,
eccsystems, Maybe only a computer aided task
(an automatic task !) could safe operate such
apparatus.
But how reliable is it ??
ALICE QGP Bar
4
The method first step, a glance on the DCS
hardware
DCS Workstation With JCOP FW(PVSS), OPCs
ECS Workstation
Ethernet
CANbus?
NT Workstation
PLC
Some actuators ( as Liq. circ. Sub -system)
HV Sub-system
Physical Parameter
FEE Sub-system
5
Second Step Satate Diagram definition, e.g. the
HV
OFF
The yellow states are automatically left when
all the related actions are accomplished.
GO_STANDBY (Config Name)
RESET
The GO_STANDBY command provides to the HV control
program the Name of the configuration to be
downloaded.
ERROR
CONFIG
GO_OFF
STATES OFF The HV power supply is switched ON
but no VH is on the channel output STANDBY all
the board and channel parameters have been
configured but no VH are on the channel
output ON after the HV Ramp Up, all the enabled
channels have the set Voltage on the
output. ERROR alarm conditions,
e.g.over-current, over-voltage,over-temperature,
, push the control system in the ERROR state.
Once the alarm condition is removed and the
operator acknowledgement is given, then it will
be possible to issue the RESET command and
restart the system
Alarm Condition
HVSS Configured !
STAND BY
All Modules are in STANDBY !
GO_ON
RMdw
RMup
ON
All Modules are in READY !
GO_RDWn
6
DELPHY HV STATE DIAGRAM (by A. Augustinus)
Crate(s) powered on and running,all channels
OFF,no values loaded to hardware
OFF
Read values from databaseand write them to
hardware
CONFIGURING_LO
Crate(s) powered on,all channels
OFF,standby values loaded to hardware
Configured_lo
Channels ramping between offand intermediate
(Standby) value (and v.v.)
RAMPING_UP_LO
RAMPING_DOWN_LO
Crate(s) powered on,all channels on intermediate
Standby values
STANDBY
Read values from databaseand write them to
hardware
CONFIGURING
Configured
lt- Is this possible as stable state???
Channels ramping between Standby valueand
operational (On) value (and v.v.)
RAMPING_UP
RAMPING_DOWN
Crate(s) powered on,all channels on operational
On values
ON
7
HMPID DCS State Diagram
OFF
GO_STANDBY (Config Name)
RESET
The GO_STANDBY command provides to the control
system the Name of the configuration to be
downloaded.
ERROR
CONFIG
GO_OFF
Alarm Condition
All Sub System are Configured !
STAND BY
All Sub System are in STANDBY !
During the Count Down to READY State, in order to
operate safely the detector, the READY commands
to all the sub systems are dispatched according
to a defined sequence. This synchronization is
ensured by the DCS control program.
GO_READY
Count Down to READY
Count Down to STANDBY
All DCS Sub Systems are READY !
READY
GO_RDWn
8
LCS Sub System State Diagram
OFF
GO_STANDBY (Config Name)
RESET
Alarm Condition
ERROR
GO_OFF
CONFIG
MANUAL
GO_STANDBY
STAND BY
LCS Configured !
GO_MAN
GO_FILL
Empty !
PURGING
FILLING
GO_PURGE
FILLEDUP
GO_PURGE
Full !
9
third step with an example given Control
Device Units Architecture
SMI Control Unit
HMPID DCS
In order to design this architecture is required
just a good detector knowledge
Working in progress
SMI Device Unit
Advanced Status
HVPS1
HMPID DCS
PLC S300
Hardware Device
HV
LV
LCS
GAS
COOL
Phis. Par
Cooling System
Gas System
HVMod 1
LCSMod 1
LVSctr 1
HVPS1
LCSMain
LVPS1
LVPS1
CAEN SY1527
PLC S300
PLC S300
WIENER PL500F8
10
How do we practically start ?

• Tools in the JCOP FW,
• PVSS provides tools to configure the CS, to log,
  archive and Graphic User Interface (basically
  monitoring),
• SMI tools are used to model Devices and
  sub-system behaviour and to automate their
  operations.

http//clara.home.cern.ch/clara/fw/FSMConfig.pdf
SMI provides tools to build Device Units,
Control Units, Domains all behaving as finite
state machine to define the Partitioning mode
Included, Excluded,StandAlone, Command Disabled,
Manual and Ignored to define the Hierarchy
rules Exclusive or Shared mode.
ALICE DCS
TPC DCS
HMPID DCS
TPC HV ss
TPC FEE ss
HMPID HV ss
11
Working with the SMI toolkit
Configuring FSM Domains. It is relevant for
Patitioning purposes
Control Unit definition
Config. Panel for Device Type
Config. Panel for Logical Object type
12
HMPID_1_domain.sml
The beginning definition
objectset HMPIDSUSY_FWSETSTATES
Cooling, GasDistribution, LiquidCirculation, L
owVoltage, Physic objectset
HMPIDSUSY_FWSETACTIONS Cooling, GasDistribution,
LiquidCirculation, LowVoltage, Physic
state CONFIG
when (( all_in HMPIDSUSY_FWSETSTATES in_state
STANDBY,DISABLED ) and ( all_in
HMPIDHVSS_FWSETSTATES in_state STANDBY,DISABLED
) ) do NV_GOTO_STANDBY
object HVSS_1_FWM is_of_class
HVSS_1_FwChildMode_CLASS objectset
FWCHILDMODE_FWSETSTATES HVSS_1_FWM objectset
FWCHILDMODE_FWSETACTIONS HVSS_1_FWM
class hmpidSUSY_CLASS/associated state
READY action GO_STANDBY state
CONFIG state ERROR action RESET
state STANDBY action GO_PHYSICS
action STOP state RAMPUP state
RAMPDOWN state OFF action START
state DISABLED action STOP object
Cooling is_of_class hmpidSUSY_CLASS object
GasDistribution is_of_class hmpidSUSY_CLASS objec
t LiquidCirculation is_of_class
hmpidSUSY_CLASS object LowVoltage is_of_class
hmpidSUSY_CLASS object Physic is_of_class
hmpidSUSY_CLASS
HMPID DCS
The control program
13
THE HMPID DCS DEVICES LOCATION
HMPID
HMPIDDCS workstation
PLC T,P
HV, SY2527
Bld 581
14
HMPID GUI operation and monitoring panel
15
HV system monitoring and control
16
Conclusions

• The FSM approach to build the sub-detector and
  ALICE DCS with building blocks
• the PVSSSMI toolkit (avail. In the JCOP F.W.)
  for the monitoring and automation respectively
  (http//clara.home.cern.ch/clara/fw/FSMConfig.pdf)
  ,
• The HMPID prototype first results and suggestions