GTI Nodes operation procedure¶

Prerequisites¶

Install NuScribe on your computer, and NuSite on your Android tablet/smartphone. Check that you have the same software version on both sides.

Required computer configuration

Operating System: Windows 10 Pro x64 Version 1809 Build 17763.107 or later
CPU: 64-bit, 2GHz, 2 cores
RAM: 32GB
Hard Drive: 1TB SSD
USB minimum 1 USB-3 port
Wi-Fi: required for NuWeb/NuSi

You need to setup your computer network configuration to be able to communicate with the Data Management Panel (DMP).

Go in your Network & Internet Settings, change ethernet adapter options
Change IPv4 properties to a static IP address
Use the following IP address 10.10.0.1 (or anything between 1 and 10 for the last segment)
Subnet mask should be 255.0.0.0 and others left empty (default)
Select OK

Warning

Never update Java on your PC as it will potentially break down NuScribe.

Prepare your acquisition¶

Setup your project in NuScribe¶

Create new project in NuScribe

Navigation

Navigate through options by clicking on the arrow on the right of the screen
Set survey projection to WGS84
Import survey .SP1 file [optional]

On the fly

Importing a survey file is not necessary if you carry out on the fly survey (i.e. if you don't know beforehand where you will collect data in the field).
At the bottom right, click on Create and wait until Success! appears on the screen. Click on OK to open the new project.

Synchronize your computer and tablet/smartphone¶

You must be connected to the same WiFi network on both the tablet and the computer, with NuScribe open.
Open the NuSite app, then synchronize users using the following credentials
- id: nuseis
- password: 123
Go to DATA -> NUWEB SYNC. It should now say that NuWeb is online and connected to the current project opened in NuScribe.

Warning

If you changed the WiFi network since last sync, you might need to reset the IP address in NuSite. Get the IPv4 address of your WiFi adapter by typing ipconfig in the command prompt.
Select Synchronize all, then press OK once it's done. Last Update should now display the current date and time.

In the field¶

Install and start up the nodes¶

Install the nodes along the desired profile.
Setting up the nodes

Depending on the field conditions, you might want to use either:
- the manual deployment tool to dig a perfect-fitted hole for the node
- the custom blue land bases with spikes
Use the bump tool to deploy the nodes. Slide the bump tool over the node cap and hold it for about one second until it starts flashing white, then quickly remove it while holding the node firmly into the ground.

Warning

Make sure the bump tool is sliding parallel to the node cap. There is a risk to bend (and eventually break) the metal parts inside the bump tool.

GPS fix

Once deployed, the node will look for GPS signal fix, then will start recording data automatically.
In the NuSite app, go to NRU, select each deployed node and click on Assign to set line and station number. You might need to manually deploy some nodes. Select the node in NuSite, then click on Connect, then your node will turn blue. Once connected, you can deploy it with the app.

Info

Each of our nodes has been assigned with a fixed ID between 1 and 130, sorted by increasing serial number. In the NuSite app, you can sort nodes by serial number, and refer to the ID/Serial Number correspondence list to ease assignment in the field.

ID / Serial numbers list

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Warning

Line and station assignment in the field can take time. Although recommended, it is not mandatory. If you know which node ID/serial number corresponds to which field station (e.g. written on a field notebook), you will be able to assign it later when back in the lab. The process is described below, but note that it is not straightforward.

Collect shots¶

Connect the EVR-2 GPS seismic event recorder to the trigger and hammer source.
Start the EVR-2 app on the tablet, then connect to the EVR-2 device.
In Settings, select Clear shot history and Reset FFID at the start of a new survey to make sure you start with a clean list.
Go in Generate points to create the list of shot stations and line numbers that you want to collect.

Warning

To ease deployment, we usually use separate numbering for node stations and shot stations. For instance, if you use 90 nodes, and record shots in between each nodes and at both ends (i.e. 91 shots total), you will have node stations ranging from 1 to 90 in the NuSite app, and shot stations ranging from 1 to 91 in the EVR-2 app. Make sure you keep track of the correspondance between station number and position along your profile or grid coordinates in the field.
Go in Shots, then check that you start with the correct Line and Station number.
Collect shots along the line (use stack option if multiple shots at the same station, or choose correct station manually).

Info

You can discard bad shots in Shot history in the EVR-2 app (long click, then omit shot), and export only correct shot timestamps.

End survey¶

If collecting a new line with the same station assignment, you don't need to undeploy the nodes. Simply move them to their new location, and change line number in EVR-2 app.

Warning

Make sure to keep the nodes upright when moving them to a new line to avoid undeploying them.

If ending the survey, simply store the nodes upside down in the carrying bag. They will undeploy automatically.

Warning

If you used the blue land base with spikes, use a small hammer to remove them from the nodes. Hit them gently with the hammer, making sure you don't damage the node.

In EVR-2 app., go in Shot history, then Output all shots with the button at the bottom-right of the screen.

Download the data¶

Synchronize your computer and tablet/smartphone¶

Start NuScribe and select current project.
Synchronize the NuSite app (cf. [Preparing your survey]). Deployments with associated Line/Station assignments should now appear in View -> Deployments.

Download data¶

In Data Panels -> DMPs, select Download sequence, then Edit Sequence to check output directory in Seismic. Create a directory in Documents/Data/your_survey/nodes_data and select it.

Warning

Make sure Output raw file is NOT checked.
Insert the first 8 [or 10] nodes in the DMP rack
Launch the sequence with the green arrow. Nodes will turn yellow, then display Serial Number, and finally turn green once data download is over.

Info

You can live check the sequence status by opening DMP Sequence panel, then right clicking on a blue cup on the rack panel and selecting Display Command Sequence. If a DMP slot is malfunctionning (i.e. serial number doesn't show), simply try again in a different slot.
Repeat steps 2 and 3 until all nodes data have been downloaded.

Import survey parameters¶

Shot timestamp file conversion¶

Connect smartphone to the PC to download the EVR-2 file (named OB_date&time.txt). Store the file in Documents/Data/your_survey/timestamps

Start Visual Studio Code and run the python script evr2_to_nuscribe.py to convert the EVR-2 file in two files (OB_date&time.sp1 and OB_date&time.sbs_ffid) that will be later required in NuScribe. At the beginning of the script, change the path of the EVR-2 file you want to convert. The new files will be stored in the same directory.

Import survey parameters in NuScribe¶

In NuScribe, go in View -> Receivers, then click on Create points from deployments (red flag with green arrow) to generate node station/line numbers.
In View -> Survey Files, import the OB_date&time.sp1 as a Source SP1 file type. Source stations should now appear as Planned in View -> Source.

Warning

Make sure you select Source instead of Receiver (which is the default option).
In View -> Sercel Files, click on Add Sercel Observer's log file and select OB_date&time.sbs_ffid, then click on Create acquired shots from observer logs. Shots should now appear in View -> Acquired shots.

Export SEGY files¶

Set up the workflow¶

Go in Data Panels -> Flows
Select the input data directory containing raw data (cf [Download data]), and the output data directory in which you want to save your SEGY files (usually Documents/Data/your_survey/segy).
Select Domain Source
Select Start Time and End Time (usually a day before the start a of the survey, and a day after the end).
Select VIBRO in Shot Process Name.
In Workers (bottom left menu), select Process Type Read Dat, then adjust output parameters (bottom right menu). All boxes should be checked except use relational template.
Sample interval should match the one defined in the nodes (250 µs by default).
Shift time by -5000 µs to add a pre-trigger delay.
Save the flow (top left). Default name is DefaultFlow.

Export SEGY files in NuScribe¶

Go to Data Panels -> Manager and Create NuTask
Select Flow Work in NuTask Type list, then FlowName (cf step 9 above) and check All Source box.
Click on Show Job Count at the bottom of the page. It should now display the correct number of sources.

Node

If multiple sources are located at the same location, it will show the number of position instead of the number of shots. Yet, it should still create the correct number of segy files.
Press OK to start creating the files.
Your files will be stored in Documents/Data/your_survey/segy/FlowName/Read Dat