Record GPS metadata

Note:

A new Collector app is available on Android and iOS. For help with the new app, see Prepare your data to record GPS metadata.

Besides geographic coordinates, you might also want to save other GPS metadata associated with a feature, such as its accuracy and fix type. Storing this metadata can be valuable to assess data quality and ensure data collection standards have been maintained. You can add GPS metadata fields to a point feature service so Collector can write GPS metadata to the respective fields when editing point features. You should also configure the feature pop-up to hide some of the data from your data collectors.

Here are a few things to keep in mind before configuring GPS metadata storage:

• GPS metadata fields are populated on point layers only.
• If a point feature is created or updated by long pressing (all platforms) or right-clicking (Windows) the map instead of using GPS, the GPS metadata fields are cleared.
• If a point feature is created or updated and GPS metadata information is not available for the GPS position, the GPS metadata fields are cleared.

Supported GPS metadata

The following GPS metadata values are recorded by Collector when using a configured feature service:

• Receiver name
• Latitude—Location before applying the specified location profile, including data transformations
• Longitude—Location before applying the specified location profile, including data transformations
• Altitude—Location before applying the specified location profile, including data transformations
• Fix time

If using a single GPS location to set a point's location, the following metadata values are also recorded:

• Horizontal accuracy
• Vertical accuracy
• PDOP
• HDOP
• VDOP
• Fix type
• Correction age
• Station ID
• Number of satellites

If performing GPS averaging to set a point's location, the following metadata values are also recorded:

• Average horizontal accuracy
• Average vertical accuracy
• Number of positions averaged
• Standard deviation

  An indication of the variation in distance between your final, averaged location and each individual location recorded during averaging. A high value indicates your position was influenced by outliers.

You can choose which of these you capture with your data: the values are ignored for any fields you don't add to your feature service. Similarly, you can set up your data for single GPS locations, averaged locations, or both: when averaging is enabled, the associated fields are populated and those for single location collection are left blank, and vice versa.

Note:

If you enabled a 95 percent confidence level for accuracy in the Collector settings, a 95 percent confidence level is used to determine if your accuracy is acceptable for data collection. The recorded accuracies are still calculated using root mean square (RMS). As such, the level of confidence in the recorded accuracies is 63 percent to 68 percent for horizontal accuracy and 68 percent for vertical accuracy.

Configure a feature service to store GPS metadata

To configure your feature service for GPS metadata storage, you can either use Python scripts or make the changes manually:

• If you use ArcGIS Desktop to publish the service, you can add the GPS metadata fields to the feature attribute tables prior to publishing the service by using the Python scripts or by manually updating your data.
• If you use ArcGIS Online or ArcGIS Enterprise to create and update your layers, you can't use Python scripts to add the GPS metadata fields to the feature attribute table. You need to make the change manually. See Manually update your data for details.

Manually update your data

To manually configure your feature service for GPS metadata storage, follow the steps below.

Caution:

Before you begin, evaluate whether you can use Python scripts instead. You should only follow these steps if you are using ArcGIS Online or ArcGIS Enterprise to create and update your layers.

1. If you want to use domains for the Fix Type, Number of Satellites, and Station ID fields you'll create in the next step, first use the details below to create the ESRI_FIX_TYPE_DOMAIN, ESRI_NUM_SATS_DOMAIN, and ESRI_STATION_ID_DOMAIN domains in your database. Using domains to populate these three fields is optional. For more information, see An overview of attribute domains in the ArcGIS Pro help.

   Note:

   Hosted feature layers created in ArcGIS Online or ArcGIS Enterprise do not support adding domains.

   • Domain 1: Coded value domain
     • Name: ESRI_FIX_TYPE_DOMAIN
     • Field type: Short integer
     • Values: 0—Fix not valid, 1—GPS, 2—Differential GPS, 4—RTK Fixed, 5—RTK Float
   • Domain 2: Range domain
     • Name: ESRI_NUM_SATS_DOMAIN
     • Field type: Short integer
     • Range: 0–99
   • Domain 3: Range domain
     • Name: ESRI_STATION_ID_DOMAIN
     • Field type: Short integer
     • Range: 0–1023
2. Determine what GPS metadata you need to capture as you do your data collection. For each piece of metadata you need to capture, add the corresponding field from the following table to the feature attribute table of the service.

   Note:

   Any fields you do not add will be ignored.

   • For feature layers hosted on ArcGIS Online, see Add a field.
   • For feature layers hosted on ArcGIS Enterprise, see Add a field.
   • For ArcGIS Server services, see Create, modify, and delete the fields of a layer or table in the ArcGIS Pro help.

   Attribute	Field alias	Field name	Field type	Domain
   Receiver name	Receiver Name	ESRIGNSS_RECEIVER	String(50)
   Horizontal accuracy	Horizontal Accuracy (m)	ESRIGNSS_H_RMS	double
   Vertical accuracy	Vertical Accuracy (m)	ESRIGNSS_V_RMS	double
   Latitude	Latitude	ESRIGNSS_LATITUDE	double
   Longitude	Longitude	ESRIGNSS_LONGITUDE	double
   Altitude	Altitude	ESRIGNSS_ALTITUDE	double
   PDOP	PDOP	ESRIGNSS_PDOP	double
   HDOP	HDOP	ESRIGNSS_HDOP	double
   VDOP	VDOP	ESRIGNSS_VDOP	double
   Fix type	Fix Type	ESRIGNSS_FIXTYPE	Short	ESRI_FIX_TYPE_DOMAIN (optional)
   Correction age	Correction Age	ESRIGNSS_CORRECTIONAGE	double
   Station ID	Station ID	ESRIGNSS_STATIONID	Short	ESRI_STATION_ID_DOMAIN (optional)
   Number of satellites	Number of Satellites	ESRIGNSS_NUMSATS	Short	ESRI_NUM_SATS_DOMAIN (optional)
   Fix time	Fix Time	ESRIGNSS_FIXDATETIME	Date
   Average horizontal accuracy	Average Horizontal Accuracy (m)	ESRIGNSS_AVG_H_RMS	double
   Average vertical accuracy	Average Vertical Accuracy (m)	ESRIGNSS_AVG_V_RMS	double
   Number of positions averaged	Averaged Positions	ESRIGNSS_AVG_POSITIONS	Long
   Standard deviation	Standard Deviation (m)	ESRIGNSS_H_STDDEV	double

Configure GPS metadata fields in the feature layer pop-up

After configuring metadata storage, it's recommended that you configure the feature layer pop-up to hide or make read-only certain GPS metadata fields from mobile workers in order to prevent these fields from being edited. You can either use Python scripts or manually update your pop-up. To use the scripts to configure a feature layer's pop-up, you need to configure it in the map as opposed to in the layer.

Tip:

If you are configuring your pop-up in the map, use Python scripts. If you are configuring it on the layer, manually update your pop-up.

Manually update your pop-up

To manually configure your pop-up on the layer to hide the associated fields, follow the steps below. See Configure the data collection form for details about editing pop-ups.

Caution:

Before you begin, evaluate whether you can use Python scripts instead. You should only follow these steps if you are configuring your pop-up on the layer instead of on the map.

1. While editing your pop-up, click Configure Attributes.
2. Uncheck Edit for each of the fields you added to capture GPS metadata in the last section. This prevents data collectors from editing the values.
3. If you want to make certain GPS metadata fields read-only, so that mobile workers can verify that they have met data collection accuracy requirements, check Display for those fields. For fields you are displaying, it is recommended that you format the field based on the following table:

   Field name	Field alias	Field format
   ESRIGNSS_RECEIVER	Receiver Name	N/A
   ESRIGNSS_H_RMS	Horizontal Accuracy (m)	2 decimal places
   ESRIGNSS_V_RMS	Vertical Accuracy (m)	2 decimal places
   ESRIGNSS_LATITUDE	Latitude	8 decimal places
   ESRIGNSS_LONGITUDE	Longitude	8 decimal places
   ESRIGNSS_ALTITUDE	Altitude	2 decimal places
   ESRIGNSS_PDOP	PDOP	2 decimal places
   ESRIGNSS_HDOP	HDOP	2 decimal places
   ESRIGNSS_VDOP	VDOP	2 decimal places
   ESRIGNSS_FIXTYPE	Fix Type	N/A
   ESRIGNSS_CORRECTIONAGE	Correction Age (seconds)	0 decimal places
   ESRIGNSS_STATIONID	Station ID	N/A
   ESRIGNSS_NUMSATS	Number of Satellites	N/A
   ESRIGNSS_FIXDATETIME	Fix Time	ShortDateTime, 12hr
   ESRIGNSS_AVG_H_RMS	Average Horizontal Accuracy (m)	2 decimal places
   ESRIGNSS_AVG_V_RMS	Average Vertical Accuracy (m)	2 decimal places
   ESRIGNSS_AVG_POSITIONS	Averaged Positions	N/A
   ESRIGNSS_H_STDDEV	Standard Deviation (m)	3 decimal places

4. If there are fields you don't want data collectors to see, uncheck Display for those fields.