States and Mode Transitions

The Dish Manager acts as the high-level orchestration TANGO device for the Dish. As such, it does not have a physical statits own; instead, it aggregates and computes its states, modes, and configurations based on the statuses of its underlying sub-elements:

• DS (Dish Structure)

• SPF (Single Pixel Feed Controller)

• SPFRx (Single Pixel Feed Receiver)

State computation is handled dynamically by evaluating a set of predefined transition rules using the rule_engine library. These rules are housed in the ska_mid_dish_manager.models.transition_rules directory.

Commands, Target States, and Aggregated Attributes

When the Dish Manager receives a command, it does not immediately change its own state. Instead, it delegates the command down to the relevant sub-elements and monitors their telemetry. The Dish Manager only transitions to the Desired State once the transition rules calculate that the Aggregated Attributes from the specific Target Sub-devices have reached their required values.

Commands	Desired dishMode	Target Sub-device(s)	Additional dishMode attribute(s)	Attributes to watch and their expected values
SetStandbyLPMode	STANDBY_LP	DS, SPF, SPFRx		operatingMode DSOperatingMode.STANDBY (DS) SPFOperatingMode.STANDBY_LP (SPF) SPFRxOperatingMode.STANDBY (SPFRx) powerState DSPowerState.LOW_POWER (DS)
SetStandbyFPMode	STANDBY_FP	DS, SPF, SPFRx		operatingMode DSOperatingMode.STANDBY (DS) powerState DSPowerState.FULL_POWER (DS)
SetStowMode	STOW	DS		operatingMode DSOperatingMode.STOW achievedPointing desiredpointingel == 90 degrees
SetMaintenanceMode	MAINTAINANCE	DS, SPF, SPFRx		operatingMode DSOperatingMode.STOW SPFRxOperatingMode.STANDBY SPFOperatingMode.MAINTENANCE
ConfigureBand [1, 2, 3, 4, 5a, 5b]	OPERATE (with new Band)	DS, SPF, SPFRx		configuredBand SPFRx.configuredband (SPF) bandInFocus SPF.bandinfocus (SPF) indexerPosition DS.indexerposition (DS)
Scan	SLEW TRACK	DS		pointingState PointingState.SLEW (DS) desiredPointing achievedPointing achievedTargetLock
Track	SLEW TRACK	DS		pointingState PointingState.SLEW (DS) desiredPointing achievedPointing achievedTargetLock
Slew	SLEW	DS		pointingState
TrackStop	READY	DS		PointingState.READY
TrackLoadStaticOff		DS		actstaticoffsetvaluexel actstaticoffsetvalueel
SetKvalue		SPFRx	KValue updated

Transition Logic and ignored sub-elements

To support engineering, maintenance, and partial-system operations, the Dish Manager allows operators to “ignore” certain sub-elements. The transition engine dynamically swaps the rule sets based on which devices are currently active or ignored. For every aggregated state, the Dish Manager defines specific rule sets such as:

• RULES_ALL_DEVICES: Evaluated when all sub-elements are communicating and monitored.

• RULES_SPF_IGNORED: Evaluated when the SPF controller is ignored.

• RULES_SPFRX_IGNORED: Evaluated when the SPFRx device is ignored.

• RULES_DS_ONLY: Evaluated when only the Dish Structure is monitor

Note

Users can configure the sub-element(s) actively being controlled and monitored by Dish Manager by setting the following boolean attributes on the dish manager interface;

• ‘ignorespf’

• ‘ignorespfrx’

Power State Transitions

The overall Dish Manager Power State (e.g., UPS, LOW_POWER, FULL_POWER, OFF) is computed by checking the power states of the sub-elements.

Power State Rule Evaluation

When calculating the aggregated Power State, the Dish Manager uses different rule dictionaries depending on whether there are any sub-elements monitored or ignored.

Below are the decision tables based on transition rules evaluated by the engine when all devices are active, as well as when sub-device(s) are ignored:

POWER_STATE_RULES_ALL_DEVICES

Rule	Condition
UPS	DS.powerstate in [‘DSPowerState.UPS’, ‘DSPowerState.OFF’]
LOW (Case 1) LOW (Case 2) LOW (Case 3)	DS.powerstate == ‘DSPowerState.LOW_POWER’
	DS.powerstate == ‘DSPowerState.UNKNOWN’ and SPF.powerstate == ‘SPFPowerState.LOW_POWER’
	DS.powerstate == ‘DSPowerState.UNKNOWN’ and SPF.powerstate == ‘SPFPowerState.UNKNOWN’
FULL (Case 1) FULL (Case 2)	DS.powerstate == ‘DSPowerState.FULL_POWER’
	DS.powerstate == ‘DSPowerState.UNKNOWN’ and |SPF.powerstate == ‘SPFPowerState.FULL_POWER’

POWER_STATE_RULES_SPF_IGNORED

Rule	Condition
UPS	DS.powerstate in [‘DSPowerState.UPS’, ‘DSPowerState.OFF’]
LOW	DS.powerstate in [‘DSPowerState.LOW_POWER’, ‘DSPowerState.UNKNOWN’]
FULL	DS.powerstate == ‘DSPowerState.FULL_POWER’

Dish Mode Transitions

Dish Mode transitions (e.g., STARTUP, STANDBY_LP, STANDBY_FP, OPERATE, STOW, MAINT) are determined by a combination of the sub-element Operating Modes, Power States, and Indexer Positions.

Dish Mode Rule Evaluation

DISH_MODE_RULES_ALL_DEVICES

Rule	Condition
STARTUP	DS.operatingmode == ‘DSOperatingMode.STARTUP’ or SPF.operatingmode == ‘SPFOperatingMode.STARTUP’ or SPFRX.operatingmode == ‘SPFRxOperatingMode.STARTUP’
STOW	DS.operatingmode == ‘DSOperatingMode.STOW’
CONFIG	SPFRX.operatingmode == ‘SPFRxOperatingMode.CONFIGURE’ or DS.indexerposition == ‘IndexerPosition.MOVING’
OPERATE	DS.operatingmode == ‘DSOperatingMode.POINT’ and SPF.operatingmode == ‘SPFOperatingMode.OPERATE’ and SPFRX.operatingmode == ‘SPFRxOperatingMode.OPERATE’
STANDBY_LP	DS.operatingmode == ‘DSOperatingMode.STANDBY’ and DS.powerstate == ‘DSPowerState.LOW_POWER’ and SPF.operatingmode != ‘SPFOperatingMode.OPERATE’
STANDBY_FP	DS.operatingmode == ‘DSOperatingMode.STANDBY’ and DS.powerstate == ‘DSPowerState.FULL_POWER’

DISH_MODE_RULES_SPF_IGNORED

Rule	Condition
STARTUP	DS.operatingmode == ‘DSOperatingMode.STARTUP’ or SPFRX.operatingmode == ‘SPFRxOperatingMode.STARTUP’
STOW	DS.operatingmode == ‘DSOperatingMode.STOW’
CONFIG	SPFRX.operatingmode == ‘SPFRxOperatingMode.CONFIGURE’ or DS.indexerposition == ‘IndexerPosition.MOVING’
OPERATE	DS.operatingmode == ‘DSOperatingMode.POINT’ and SPFRX.operatingmode == ‘SPFRxOperatingMode.OPERATE’
STANDBY_LP	DS.operatingmode == ‘DSOperatingMode.STANDBY’ and DS.powerstate == ‘DSPowerState.LOW_POWER’
STANDBY_FP	DS.operatingmode == ‘DSOperatingMode.STANDBY’ and DS.powerstate == ‘DSPowerState.FULL_POWER’

DISH_MODE_RULES_SPFRX_IGNORED

Rule	Condition
STARTUP	DS.operatingmode == ‘DSOperatingMode.STARTUP’ or SPF.operatingmode == ‘SPFOperatingMode.STARTUP’
STOW	DS.operatingmode == ‘DSOperatingMode.STOW’
CONFIG	DS.indexerposition == ‘IndexerPosition.MOVING’
OPERATE	DS.operatingmode == ‘DSOperatingMode.POINT’ and SPF.operatingmode == ‘SPFOperatingMode.OPERATE’
STANDBY_LP	DS.operatingmode == ‘DSOperatingMode.STANDBY’ and DS.powerstate == ‘DSPowerState.LOW_POWER’ and SPF.operatingmode != ‘SPFOperatingMode.OPERATE’
STANDBY_FP	DS.operatingmode == ‘DSOperatingMode.STANDBY’ and DS.powerstate == ‘DSPowerState.FULL_POWER’

DISH_MODE_RULES_DS_ONLY

Rule	Condition
STARTUP	DS.operatingmode == ‘DSOperatingMode.STARTUP’
STOW	DS.operatingmode == ‘DSOperatingMode.STOW’
CONFIG	DS.indexerposition == ‘IndexerPosition.MOVING’
OPERATE	DS.operatingmode == ‘DSOperatingMode.POINT’
STANDBY_LP	DS.operatingmode == ‘DSOperatingMode.STANDBY’ and DS.powerstate == ‘DSPowerState.LOW_POWER’
STANDBY_FP	DS.operatingmode == ‘DSOperatingMode.STANDBY’ and DS.powerstate == ‘DSPowerState.FULL_POWER’

Band and Pointing Configurations

Dish Band Configuration rules

The Band Configuration state (e.g., OPERATE with a specific band) is determined by evaluating the configured band on the SPFRx, the band in focus on the SPF, and the indexer position on the DS. A transient change to the CONFIG mode may also occur during band changes.

CONFIGURED_BAND_RULES_ALL_DEVICES

Rule	Condition
NONE	SPFRX.configuredband == ‘Band.NONE’
B1	DS.indexerposition == ‘IndexerPosition.B1’ and SPFRX.configuredband == ‘Band.B1’ and SPF.bandinfocus == ‘SPFBandInFocus.B1’
B2	DS.indexerposition == ‘IndexerPosition.B2’ and SPFRX.configuredband == ‘Band.B2’ and SPF.bandinfocus == ‘SPFBandInFocus.B2’
B3	DS.indexerposition == ‘IndexerPosition.B3’ and SPFRX.configuredband == ‘Band.B3’ and SPF.bandinfocus == ‘SPFBandInFocus.B3’
B4	DS.indexerposition == ‘IndexerPosition.B4’ and SPFRX.configuredband == ‘Band.B4’ and SPF.bandinfocus == ‘SPFBandInFocus.B4’
B5a	DS.indexerposition == ‘IndexerPosition.B5a’ and SPFRX.configuredband == ‘Band.B5a’ and SPF.bandinfocus == ‘SPFBandInFocus.B5a’
B5b	DS.indexerposition == ‘IndexerPosition.B5b’ and SPFRX.configuredband == ‘Band.B1’ and SPF.bandinfocus == ‘SPFBandInFocus.B5b’

CONFIGURED_BAND_RULES_SPF_IGNORED

Rule	Condition
NONE	SPFRX.configuredband == ‘Band.NONE’
B1	DS.indexerposition == ‘IndexerPosition.B1’ and SPFRX.configuredband == ‘Band.B1’
B2	DS.indexerposition == ‘IndexerPosition.B2’ and SPFRX.configuredband == ‘Band.B2’
B3	DS.indexerposition == ‘IndexerPosition.B3’ and SPFRX.configuredband == ‘Band.B3’
B4	DS.indexerposition == ‘IndexerPosition.B4’ and SPFRX.configuredband == ‘Band.B4’
B5a	DS.indexerposition == ‘IndexerPosition.B5a’ and SPFRX.configuredband == ‘Band.B5a’
B5b	DS.indexerposition == ‘IndexerPosition.B5b’ and SPFRX.configuredband == ‘Band.B1’

CONFIGURED_BAND_RULES_SPFRX_IGNORED

Rule	Condition
B1	DS.indexerposition == ‘IndexerPosition.B1’ and SPF.bandinfocus == ‘SPFBandInFocus.B1’
B2	DS.indexerposition == ‘IndexerPosition.B2’ and SPF.bandinfocus == ‘SPFBandInFocus.B2’
B3	DS.indexerposition == ‘IndexerPosition.B3’ and SPF.bandinfocus == ‘SPFBandInFocus.B3’
B4	DS.indexerposition == ‘IndexerPosition.B4’ and SPF.bandinfocus == ‘SPFBandInFocus.B4’
B5a	DS.indexerposition == ‘IndexerPosition.B5a’ and SPF.bandinfocus == ‘SPFBandInFocus.B5a’
B5b	DS.indexerposition == ‘IndexerPosition.B5b’ and SPF.bandinfocus == ‘SPFBandInFocus.B5b’

CONFIGURED_BAND_RULES_DS_ONLY

Rule	Condition
B1	DS.indexerposition == ‘IndexerPosition.B1’
B2	DS.indexerposition == ‘IndexerPosition.B2’
B3	DS.indexerposition == ‘IndexerPosition.B3’
B4	DS.indexerposition == ‘IndexerPosition.B4’
B5a	DS.indexerposition == ‘IndexerPosition.B5a’
B5b	DS.indexerposition == ‘IndexerPosition.B5b’

Pointing State

Reflects whether the Dish is READY, SLEW, or TRACK. This state relies almost entirely on the Dish Structure (DS) tracking telemetry.

Dish Health States

The Dish Manager also computes aggregated health states such as OK, DEGRADED, FAILED, and UNKNOWN based on the health states of the sub-devices.

Dish Health State Rule Evaluation

HEALTH_STATE_RULES_ALL_DEVICES

Rule	Condition
DEGRADED	DS.healthstate == ‘HealthState.DEGRADED’ and SPF.healthstate in [‘HealthState.OK’, ‘HealthState.DEGRADED’, ‘HealthState.UNKNOWN’] and SPFRX.healthstate in [‘HealthState.OK’, ‘HealthState.DEGRADED’, ‘HealthState.UNKNOWN’]
	or
	DS.healthstate in [‘HealthState.OK’, ‘HealthState.DEGRADED’, ‘HealthState.UNKNOWN’] and SPF.healthstate == ‘HealthState.DEGRADED’ and SPFRX.healthstate in [‘HealthState.OK’, ‘HealthState.DEGRADED’, ‘HealthState.UNKNOWN’]
	or
	DS.healthstate in [‘HealthState.OK’, ‘HealthState.DEGRADED’, ‘HealthState.UNKNOWN’] and SPF.healthstate in [‘HealthState.OK’, ‘HealthState.DEGRADED’, ‘HealthState.UNKNOWN’] and SPFRX.healthstate == ‘HealthState.DEGRADED’
FAILED	DS.healthstate == ‘HealthState.FAILED’ or SPF.healthstate == ‘HealthState.FAILED’ or SPFRX.healthstate == ‘HealthState.FAILED’
OK	DS.healthstate == ‘HealthState.OK’ and SPF.healthstate == ‘HealthState.OK’ and SPFRX.healthstate == ‘HealthState.OK’
UNKNOWN	DS.healthstate == ‘HealthState.UNKNOWN’ or SPF.healthstate == ‘HealthState.UNKNOWN’ or SPFRX.healthstate == ‘HealthState.UNKNOWN’

HEALTH_STATE_RULES_SPF_IGNORED

Rule	Condition
DEGRADED	DS.healthstate == ‘HealthState.DEGRADED’ and |SPFRX.healthstate in [‘HealthState.OK’, ‘HealthState.DEGRADED’, ‘HealthState.UNKNOWN’]
	or
	DS.healthstate in [‘HealthState.OK’, ‘HealthState.DEGRADED’, ‘HealthState.UNKNOWN’] and SPFRX.healthstate == ‘HealthState.DEGRADED’
FAILED	DS.healthstate == ‘HealthState.FAILED’ or SPFRX.healthstate == ‘HealthState.FAILED’
OK	DS.healthstate == ‘HealthState.OK’ and SPFRX.healthstate == ‘HealthState.OK’
UNKNOWN	DS.healthstate == ‘HealthState.UNKNOWN’ or SPFRX.healthstate == ‘HealthState.UNKNOWN’

HEALTH_STATE_RULES_SPFRX_IGNORED

Rule	Condition
DEGRADED	DS.healthstate == ‘HealthState.DEGRADED’ and SPF.healthstate == ‘HealthState.DEGRADED’ SPF.healthstate in [‘HealthState.OK’, ‘HealthState.DEGRADED’, ‘HealthState.UNKNOWN’]
	or
	DS.healthstate in [‘HealthState.OK’, ‘HealthState.DEGRADED’, ‘HealthState.UNKNOWN’] and SPF.healthstate == ‘HealthState.DEGRADED’
FAILED	DS.healthstate == ‘HealthState.FAILED’ or SPF.healthstate == ‘HealthState.FAILED’
OK	DS.healthstate == ‘HealthState.OK’ and SPF.healthstate == ‘HealthState.OK’
UNKNOWN	DS.healthstate == ‘HealthState.UNKNOWN’ or SPF.healthstate == ‘HealthState.UNKNOWN’

HEALTH_STATE_RULES_DS_ONLY

Rule	Condition
DEGRADED	DS.healthstate == ‘HealthState.DEGRADED’
FAILED	DS.healthstate == ‘HealthState.FAILED’
OK	DS.healthstate == ‘HealthState.OK’
UNKNOWN	DS.healthstate == ‘HealthState.UNKNOWN’