CSD - Range, Hor. Angle, Bearing & Vert. Angle

Surface Navigation System

Observations defined under a Surface Navigation System are: Range, Angle, Bearing (True) and Vertical Angle.

Add a new system by selecting “Edit” from the menu bar, and then “New” and “System”, or right click on the item System in the item tree.

The following dialog opens. It is the first page of a wizard that steps you through the system definition process.

Enter an appropriate name that provides instant recognition in Online displays of what and where it is.

Select Surface Navigation System from the drop down list.

Select the appropriate driver that will decode the sensor messages sent to the software.

The driver list includes both serial and network drivers. If you have already defined other systems and some of the data messages are sent by the dredger's PLC, it is likely that this data will also be issued by the PLC.

Enter interface port parameters.

Please refer to A Note on Interfacing Parameters.

Enter the data update parameters. Depending on the driver selected one or other, or both, these parameters are shown:

Updates

Maximum update rate

Enter a value to determine how often data will be decoded by the interface driver. Some equipment is capable of outputting data at high output rates, but it may not be necessary to use each update. A motion sensor system may for example output values hundreds of times per second, where twenty times per second is sufficient. In this case, enter a value of 0.05s. Any data not decoded by the driver is lost and cannot be recovered later.

Latency

Latency is the time between the actual measurement made in the motion sensor system and the time the data message arrives at the port. The time in QINSy will thus be the arrival time corrected with the latency.
Modern motion sensor systems will exhibit no latency, or will have compensated for the latency in the time tag of each data message.

Press Next to advance to the second page of the wizard which will look like this:

Select one of the four observation types.

Select the object FROM which the observation is made.

Select the node FROM which the observation is made.

Click on the Add button to select the node TO which the observation is being measured. A new dialog pops up in which the observation name is entered.

If the node you want is not yet defined (i.e. appearing in the list) use the

button to add a new Variable node.
If the node you want is not yet defined (i.e. appearing in the list) use the

button to add a new Fixed node.

Click OK to return to the Define Observations dialog which should now list the observation just defined.

Click Add again in this dialog to define additional observations if they are needed.

For each new observation defined press Apply Name.

Click OK to return to the Observation Definition dialog where the defined observations are listed.

Then Click Next to advance to the last page of the wizard.

Enter all the observation parameters for each observation listed on the left.

Observation parameters
Name	Enter a descriptive name for the observation.
Unit	Select the appropriate observation unit. In some cases there will only be one choice.
a-priori SD	Enter the SD for each observation in turn.
Fixed C-O	Constant correction to the parameter value.
Variable C-O	Variable correction to the parameter value.
Scale factor	Use scale factor to convert the raw output to units in the Acquisition Software. For example if local output is in centimeters, then enter scale factor 0.01 here to convert to meters.
Apply C-Os offsets first	C-Os are added or subtracted before a scale factor is applied.
Apply Scale factor first	Scale factor is applied before C-Os are applied.
Apply automatically	The order in which corrections are applied is done in the software.

Click Finish to complete the Surface Navigation System definition.

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