Restrictions on datatype/unit

[danielwilms]

First idea was using schema:rangeIncludes. Other ideas from @felix-loesch

• Option A: create OWL restrictions to store that information at the class level or solution
• option B: create master instances to store that information.

[felix-loesch]

I strongly suggest that we move the concrete VSS definitions (e.g. signals, branches) to OWL instances.
This makes defining the restrictions much easier than leaving them at the class level.

[danielwilms]

issue is related to #22 and should be discussed after #22 is decided.

[danielwilms]

Possible tooling extension for:
arrays: COVESA/vss-tools@4fc8709
units: COVESA/vss-tools@8065958
enumerations: COVESA/vss-tools@417db9b

[danielwilms]

@jdacoello will create proposal until 2022/05/30 for discussion

[jdacoello]

Here is a proposal to handle values and units.

Current problem/drawback

To give some context, as of today, a VehicleProperty can have a value and its associated datetime via direct data properties as shown below:

PROS:

• Simple structures and queries

CONS:

• To overwrite (i.e., update) the value, one must delete and then insert a new one
• The intention of this approach only focuses to answer: what is the current value?
• Any other information needed (e.g., unit) requires a new data property. Although possible and valid, this approach would prevent in practice having values in other units at the same time.
• As it was resolved in the VSS Ontology Workshop on 14.03, Specific DynamicVehicleProperty coming from VSS are now implemented as instances.
• Let's visualise the implications of the current status:
  

You can see in the figure how multiple values coming from different vehicles are linked to the same instance of a DynamicVehicleProperty, in this case Speed. So, the membership of these literals become unclear when multiple vehicles are instantiated and using the same instance of a DynamicVehicleProperty.

Proposal

I propose to have the following structure:

Here, the class VehiclePropertyValue (in orange) is introduced. In practice, this means that a specific vehicle will have specific values of the properties linked to it. If the concept is used to assign the type to a blank node, we could arbitrarily add any other metadata that might be needed (e.g., unit).

If the unit is fixed, make it part of the model

If the unit is not fixed, introduce quantity kind for correctness

Adopt an existing ontology for units and quantity kinds (e.g., QUDT)

VSS has the specification for the unit and the dimension to which it relates. We can use it to map into concrete instances of unit and quantity kind. Taking the extensive QUDT ontology as the reference:

Unit type	Unit (QUDT)	Domain	QuantityKind (QUDT)	Description
cm/s^2	http://qudt.org/vocab/unit/CentiM-PER-SEC2	Acceleration	http://qudt.org/vocab/quantitykind/Acceleration	Acceleration measured in centimeters per second squared
m/s^2	http://qudt.org/vocab/unit/M-PER-SEC2	Acceleration	http://qudt.org/vocab/quantitykind/Acceleration	Acceleration measured in meters per second squared
degrees	http://qudt.org/vocab/unit/DEG	Angle	http://qudt.org/vocab/quantitykind/Angle	Angle measured in degrees
degrees/s	http://qudt.org/vocab/unit/DEG-PER-SEC	Angular Speed	http://qudt.org/vocab/quantitykind/AngularVelocity	Angular speed measured in degrees per second
rpm	http://qudt.org/vocab/unit/REV-PER-MIN	Rotational Speed	http://qudt.org/vocab/quantitykind/AngularVelocity	Rotational speed measured in revolutions per minute
percent	http://qudt.org/vocab/unit/PERCENT	Relation	http://qudt.org/vocab/quantitykind/DimensionlessRatio	Relation measured in percent
ratio	http://qudt.org/vocab/unit/UNITLESS	Relation	http://qudt.org/vocab/quantitykind/DimensionlessRatio	Relation measured as ratio
A	http://qudt.org/vocab/unit/A	Electric Current	http://qudt.org/vocab/quantitykind/ElectricCurrent	Electric current measured in amperes
V	http://qudt.org/vocab/unit/V	Electric Potential	http://qudt.org/vocab/quantitykind/ElectricPotential	Electric potential measured in volts
kWh	http://qudt.org/vocab/unit/KiloW-HR	Energy Consumption	http://qudt.org/vocab/quantitykind/Energy	Energy consumption measured in kilowatt hours
N	http://qudt.org/vocab/unit/N	Force	http://qudt.org/vocab/quantitykind/Force	Force measured in newton
kPa	http://qudt.org/vocab/unit/KiloPA	Pressure	http://qudt.org/vocab/quantitykind/ForcePerArea	Pressure measured in kilopascal
mbar	http://qudt.org/vocab/unit/MilliBAR	Pressure	http://qudt.org/vocab/quantitykind/ForcePerArea	Pressure measured in millibars
Pa	http://qudt.org/vocab/unit/PA	Pressure	http://qudt.org/vocab/quantitykind/ForcePerArea	Pressure measured in pascal
Hz	http://qudt.org/vocab/unit/HZ	Frequency	http://qudt.org/vocab/quantitykind/Frequency	Frequency measured in hertz
cm	http://qudt.org/vocab/unit/CentiM	Distance	http://qudt.org/vocab/quantitykind/Length	Distance measured in centimeters
inch	http://qudt.org/vocab/unit/IN	Distance	http://qudt.org/vocab/quantitykind/Length	Distance measured in inches
km	http://qudt.org/vocab/unit/KiloM	Distance	http://qudt.org/vocab/quantitykind/Length	Distance measured in kilometers
m	http://qudt.org/vocab/unit/M	Distance	http://qudt.org/vocab/quantitykind/Length	Distance measured in meters
mm	http://qudt.org/vocab/unit/MilliM	Distance	http://qudt.org/vocab/quantitykind/Length	Distance measured in millimeters
g	http://qudt.org/vocab/unit/GM	Weight	http://qudt.org/vocab/quantitykind/Mass	Mass measured in grams
kg	http://qudt.org/vocab/unit/KiloGM	Weight	http://qudt.org/vocab/quantitykind/Mass	Mass measured in kilograms
lbs	http://qudt.org/vocab/unit/LB	Weight	http://qudt.org/vocab/quantitykind/Mass	Mass measured in pounds
g/s	http://qudt.org/vocab/unit/GM-PER-SEC	Mass per time	http://qudt.org/vocab/quantitykind/MassFlowRate	Mass per time measured in grams per second
g/km	http://qudt.org/vocab/unit/GM-PER-KiloM	Mass per distance	http://qudt.org/vocab/quantitykind/MassPerLength	Mass per distance measured in grams per kilometers
PS	http://qudt.org/vocab/unit/HP_Metric	Power	http://qudt.org/vocab/quantitykind/Power	Power measured in horsepower
kW	http://qudt.org/vocab/unit/KiloW	Power	http://qudt.org/vocab/quantitykind/Power	Power measured in kilowatts
W	http://qudt.org/vocab/unit/W	Power	http://qudt.org/vocab/quantitykind/Power	Power measured in watts
celsius	http://qudt.org/vocab/unit/DEG_C	Temperature	http://qudt.org/vocab/quantitykind/Temperature	Temperature measured in degree celsius
day	http://qudt.org/vocab/unit/DAY	Time	http://qudt.org/vocab/quantitykind/Time	Time measured in days
h	http://qudt.org/vocab/unit/HR	Time	http://qudt.org/vocab/quantitykind/Time	Time measured in hours
ms	http://qudt.org/vocab/unit/MilliSEC	Time	http://qudt.org/vocab/quantitykind/Time	Time measured in milliseconds
min	http://qudt.org/vocab/unit/MIN	Time	http://qudt.org/vocab/quantitykind/Time	Time measured in minutes
months	http://qudt.org/vocab/unit/MO	Time	http://qudt.org/vocab/quantitykind/Time	Time measured in months
s	http://qudt.org/vocab/unit/SEC	Time	http://qudt.org/vocab/quantitykind/Time	Time measured in seconds
weeks	http://qudt.org/vocab/unit/WK	Time	http://qudt.org/vocab/quantitykind/Time	Time measured in weeks
years	http://qudt.org/vocab/unit/YR	Time	http://qudt.org/vocab/quantitykind/Time	Time measured in years
Nm	http://qudt.org/vocab/unit/N-M	Torque	http://qudt.org/vocab/quantitykind/Torque	Torque measured in newton meters
km/h	http://qudt.org/vocab/unit/KiloM-PER-HR	Speed	http://qudt.org/vocab/quantitykind/Velocity	Speed measured in kilometers per hours
m/s	http://qudt.org/vocab/unit/M-PER-SEC	Speed	http://qudt.org/vocab/quantitykind/Velocity	Speed measured in meters per second
cm^3	http://qudt.org/vocab/unit/CentiM3	Volume	http://qudt.org/vocab/quantitykind/Volume	Volume measured in cubic centimeters
l	http://qudt.org/vocab/unit/L	Volume	http://qudt.org/vocab/quantitykind/Volume	Volume measured in liters
ml	http://qudt.org/vocab/unit/MilliL	Volume	http://qudt.org/vocab/quantitykind/Volume	Volume measured in milliliters
l/h	http://qudt.org/vocab/unit/L-PER-HR	Flow	http://qudt.org/vocab/quantitykind/VolumeFlowRate	Flow measured in liters per hour
kWh/100km	NA	Energy Consumption per distance	NA	Energy consumption per distance measured in kilowatt hours per 100 kilometers
l/100km	NA	Volume per distance	NA	Volume per distance measured in liters per 100 kilometers
ml/100km	NA	Volume per distance	NA	Volume per distance measured in milliliters per 100 kilometers
mpg	NA	Distance per Volume	NA	Distance per volume measured in miles per gallon
stars	Not used	Rating	Not used	Rating measured in stars
UNIX Timestamp	Not used	Time	Not used	Unix time is a system for describing a point in time. It is the number of seconds that have elapsed since the Unix epoch, excluding leap seconds.

[danielwilms]

Meeting 2022/06/27:

1. We go with a new property called vsso-core:VehiclePropertyValue instead of previous solution (maybe use for SVP) (used in OMP as well as pattern)
2. Rather use concrete units instead of QuantityKind

[danielwilms]

• @jdacoello create PR for vsso-core
• @danielwilms adapt the vss-tools to use it

[jdacoello]

@rtroncy will provide a counter proposal that is based on cudt.