Candidate Sensor Description Terms

This is a list of descriptive metadata fields we developed for the Track 2 training. It includes the common descriptive metadata terms deemed most often useful in working with sensor data.

For Track 1, you are welcome to use this list, modify it, or create your own list.

Sensor Information

Note that in this document, the term 'sensor' is meant to describe any device (aka instrument) that measures one or more things. A sensor may itself include other sensors. Sensors include transducers (described below) to do the actual measuring.

If a sensor contains other sensors, these terms are repeated for each subsensor.

sensor id

unique number or string that identifies the device

sensor name

optional free text name according to user convention

sensor manufacturer

name of the company or organization making the device

sensor model number

model number assigned by the manufacturer to this device

sensor serial number

serial number assigned by the manufacturer to this device

sensor type

term from a controlled vocabulary that indicates the function of this device

Transducer Information

A transducer may only measure or control one thing. Each transducer is considered to have only one input and only one output. Although in general the transducer can have the physical world on either the input or the output side, in this document we are only worrying about the case where the real world is being turned into measurements.

The transducer terms are repeated for each transducer.

transducer id

unique number or string that identifies the component

transducer name

optional free text name of the component according to user convention

transducer manufacturer

name of the company or organization making the component

transducer model number

model number assigned by the manufacturer to this component

measurand

property measured by this component

Data Record Information

The sensor may put out multiple data records, of different formats. If these records are of well-defined formats, they can be described enough for a computer to automatically parse and process them.

If the sensor puts out records whose format changes and is not easily described, this makes automation of the processing very difficult. (It also makes understanding the data years later, or without the manual, hard to impossible.) Each record in that case can only be broadly described.

The data record terms are repeated for each data record.

data record id

unique number or string that identifies the component

data record name

a free text name according to user convention

asciionly

indicates whether record is entirely composed of ASCII characters; if not, record is considered "binary" (can contain non-ASCII characters)

field delimiter

what delimiter(s) separate each field in a record of this type

line delimiter

what delimiter(s) separate line in a record of this type

Data Variable Information

The sensor may put out multiple data variables, or values, in each data record. Metadata descriptions enable systems to provide searchable discovery of data produced by the sensor, and to automatically process data in many different ways.

The data variable terms are repeated for each variable.

variable id

unique number or string that identifies the component

variable name

a free text name according to user convention

units

the unit of measure used for this variable; should be from a controlled vocabulary

standard name mapping(s)

term from another controlled vocabulary that is the equivalent of this variable; the controlled vocabulary should be specified as part of the term

legal value range

minimum and maximum values that this sensor can represent

nominal value range

minimum and maximum values that this sensor can measure within the specified error

specified measurement error

maximum error the transducer allows when calibrated

More advanced information may be necessary or useful in describing highly structured data, but we have not incorporated that explicitly in this exercise.

Dynamic Information

The following information can change over the lifetime of a sensor. We have included it because it is a part of describing the sensor, but it may not be appropriate to describe it in the same metadata structure as the static information above.

People Roles

There are mulitple roles that a person can occupy with respect to a sensor (see for example ISO 19115 roles). We have chosen two, 'owner' and 'maintainer', although the ability to represent any of a number of roles should be considered.

For each role, the following concepts should be addressed.

organization (identity information

the name and other identifying information of the organization in this role

person (identity info)

the name and other identifying information of the person in this role

contact info

how to reach the person in this role

System Terms

These terms describe the platform or other physical context in which the sensor is deployed. The system in which the sensor is deployed is called the "parent system."

Note that a system could be a parent in different roles (one system could provide power, another could provide communications, and a third could provide the mounting structure for a sensor. These terms do not address that subtlety.

system id

unique number or string that identifies the system

system name

a free text name according to user convention

Deployment Terms

nominal location (x, y, z)

the intended geographical location of the sensor/platform (not a measurement value that's constantly updated)

nominal location error (x, y, z)

how far off can the nominal location be in each axis

date deployed

when was the sensor deployed on its parent system

Other descriptors may also be appropriate for fully capturing the sensor's position relative to the world. These could include:

• the attitude of the platform as deployed
• relative location and attitude of the sensor to the platform
• errors in the attitude and relative position information

Sensor Calibration and Quality Assurance Terms

This information can be repeated for every individual procedure performed.

procedure

the calibration, quality assurance, or other procedure used to assure sensor is performing as desired

procedure date

when the pocedure took place

procedure description

detailed text, or pointer to same, describing the exact activities involved in this procedure

performer

person or role performing the procedure (identification information)

organization

organization responsible for performing the procedure

controlled procedure results

the formal output(s) of the procedure (typically generated automatically

comments

additional information about the procedure