Instrumented Assemblies > Using Sensors > About Sensors
  
About Sensors
A sensor is a model with a special set of parameters and communication capabilities. Any model can be converted to a sensor or converted back to a regular model from the Model Properties dialog box. Sensor parameters have pre-defined names, types, and units that are driven by the sensor specification. The default is to add parameters to a sensor from an XML sensor file. Sensor parameters represent the interface with the real physical sensor. For each occurrence of the sensor model the parameters can get different values. A physical sensor has geometry, participates in Mass Properties, and is part of the BOM.
The following Creo Parametric models can be designated as sensors:
Design part
Sheetmetal part
Design assembly
 
* Sensor is a property of the entire Family Table. When the generic model is a sensor all members of the Family Table are sensors.
There are 2 types of data a sensor can receive or transmit, measured data or calculated data.
Measured—Measures something in the ‘real world’ and sends the data back to the model. This data can be used in Creo Parametric for emulation of real-life conditions.
Calculated—Data is calculated in Creo Parametric and can be communicated to the model.
Data from sensors, communicated via parameters, can be used in the 3D model to perform the following actions:
Update the model design state according to the change in state of the paired physical model.
Provide analysis of 3D model state.
Provide analysis of the effect of the physical surroundings on the current model.
For visualization purposes such as those listed below:
To show kinematic motion
To represent loads applied on the 3D model
To visually show sensor data as a notification attached to the sensor location
There are two types of sensors:
Physical sensors—Inserted as sensor components in the assembly. Physical sensors appear in the BOM, have mass properties, and are similar to other components in the assembly.
Virtual sensors—Inserted as features and do not have a visible component in the assembly. They have sensor parameters and are similar to Analysis features. The data type of a virtual sensor is always Calculated. The data can come from Creo Parametric or PTC Mathcad. Virtual sensors do not appear in the BOM, are not taken into account in analyses, and do not have mass properties.
You can add a sensor to a model during the design process or after release when the model is in production. Use an Instrumented Assembly to add sensors to a model after production.
You can use measured and calculated sensors in tandem. For example, a measured sensor measures temperature and a calculated sensor performs thermal analysis and returns the results.
Sensor Parameters
A sensor parameter can have a single value or can be defined as a series parameter that contains a table of values. The table defines a parameter that changes over time. Values for the parameters are set for each sensor during or after placement in the model.
A sensor can have regular parameters or series parameters, but not both types of parameters. A sensor model is defined with a regular parameter, you change the type of parameter to a series parameter after the sensor component is assembled. When you connect a calculated sensor with a series parameter, an Analysis Measure must be defined for each time stamp.
A sensor gets the parameter values from outside measurements imported from a ThingWorx server, from a file, or from Creo Parametric analysis calculations. You can also change sensor parameter values manually when you perform one of the following operations:
Double-click a sensor parameter value in the graphics window
Open the Sensor Info and Setup dialog box
Open the Parameters dialog box
To clear all sensor parameter data from the model, click Sensor > Clear Data.
When you make a fundamental change to the Sensor Model, such as a change to the units and unit quantity of a sensor parameter, you must update sensor parameters after regeneration. Right-click the Sensor Model in the Model Tree and click Sensor > Update Sensor Parameters. Click OK to update the sensor parameters.
When you connect to a ThingWorx server, you can use sensors to match a physical model to the digital model.
 
* Sensor parameters used in communication with a ThingWorx server, must have names that meet the ThingWorxnaming conventions. These are generally stricter than the Creo Parametric naming conventions.
Converting a Regular Parameter to a Series Parameter
Follow the steps below to change a regular parameter to a series parameter after the sensor is inserted in the model.
1. Select the parameter in the Parameters dialog box.
2. Right-click, and select Series. You are prompted to confirm.
3. Click OK. The Parameter Properties dialog box opens to the Series tab.
4. Click . A new row is added to the table.
5. To add rows to the table, double-click the value or click .
6. Continue adding rows until the table is complete and click OK.