The Dynamic System Animation module main input form is shown in Figure 1.  The form is organized into 3 input groups:

• System Definition
• Response Type
• Response Data

The System Definition input group contains buttons for opening the System Definition Worksheet and for previewing the system. The Response Type input group specifies the type of dynamic response data to be processed and animated. The Response Data input group provides 2 options for entering response data and linking it to the system geometry. Each input group is described in more detail in the sections that follow.

Figure 1. Dynamic System Animation main input form

Defining the System

The first step in creating an animation is to define the geometry and connectivity of the dynamic system. Press the Define System button to open the System Definition Worksheet shown in Figure 2. Each row of the worksheet corresponds to a node point to be animated. Each row contains 15 input fields that correspond to the 15 columns in the worksheet. A description of the first 5 input fields is provided below.

Figure 2. System Definition Worksheet

Viewing the System

After defining the locations of the nodes and how they are connected, click the Back button to return to the main input form. Then click the Preview button to open an ETBX Animation Panel as shown in Figure 3. The Animation Panel displays the dynamic system and provides controls for manipulating the view, such as rotating, panning, and zooming.

This Preview function allows you to verify that the system was defined correctly prior to entering response data. Note in Figure 3 that there are no results cases and the Deformed button is ghosted. The Preview function does not process response data and will not generate an animation.

Figure 3. System preview

Specifying the Response Type and Format

To define the system response, return to the module's main input form. The Response Type input group shown in Figure 4 provides several controls for specifying the format of the response data. Click on the Response Type drop-down menu to select the type of response to be input and animated. Version 1.1 of the Dynamic Animation module only supports Frequency Response data. Future versions may support additional response types, such as Time History data.

Frequency response data consists of complex numbers that may be defined using real/imaginary pairs, or in polar form by entering the magnitude and phase angle of the response. Select the Real-Imaginary option to enter real and imaginary components of response. Select the Magnitude-Phase option to enter the magnitude and phase of the response. Phase may be defined as a positive angle (Phase Lead) or negative angle (Phase Lag) with respect to the real axis as shown in Figure 5. Be sure to select the option (Phase Lead or Phase Lag) that is consistent with the input data.

Figure 4. Response Type Input Group

Figure 5. Phase Angle Sign Conventions

Response Data Entry

The response at each node is defined in columns 6 through 11 of the System Definition worksheet as shown in Figure 6. The required input values are dependent on the response format selected on the module's main input form (see Figure 4). For example, if the Real-Imaginary option is selected, the proper input values are the real and imaginary components of the response. An information bar at the bottom of the System Definition worksheet provides a brief description of the expected input. The location of the information bar is shown in Figure 6.

Figure 6. System response data entry

The Response Data input group, shown in Figure 7 , provides two options for defining nodal response. The first option is labeled Numerical Values (Single Frequency). Choose this option to enter numerical values in columns 6 through 11 of the System Definition worksheet as shown in Figure 6. This is the quickest method of defining system response at a single frequency.

The second option is labeled Data Codes (Multiple Frequencies). Choose this option to enter alphanumeric identifiers called data codes in columns 6 through 11 as shown in Figure 8. The numerical values associated with the data codes are defined in the System Response worksheet, which can be opened by clicking the Define Data Codes button. The use of data codes makes it easy to define system response values for a range of frequencies.

Figure 7. Response Data input group

Figure 8. Data codes can be entered in the System Definition worksheet

Response Input Fields

Regardless of the response type, format, and data entry method you select on the main input form, the response at each node is defined in Columns 6 through 11 of the System Definition worksheet. Blank fields are allowed in Columns 6 through 11 and are interpreted as zero values. A description of these input fields is given below.

Response Scale Factors

Scale factors can be applied to each component (X, Y, Z) of response in Columns 12 through 14 of the System Definition worksheet. If Real-Imaginary format is selected, both the real and imaginary parts of the response are multiplied by the specified factor. If Magnitude-Phase format is selected, the response magnitudes are multiplied by the scale factor. Phase angles are not affected by scale factors. Columns 12 through 14 may be left blank to specify a scale factor of 1.0. A description of the input fields is given below.

Using Data Codes and the System Response Worksheet

Data codes are alphanumeric identifiers that can be entered in Columns 6 through 11 of the System Definition worksheet to specify a component of response (see Figure 8). The numerical values associated with data codes are defined in the System Response worksheet, shown in Figure 9. The use of data codes to define system response requires the following:

• The option labeled Data Codes (Multiple Frequencies) must be selected in the Response Data input group of the main input form as shown in Figure 7.
• Data codes must only consist of letters, numbers, dollar signs, or underscore characters.
• Each data code referenced in the System Definition worksheet must have a corresponding entry (i.e., must be defined) in the System Response worksheet.
• Data codes are not case sensitive. For example, N01XRM is the same as n01xrm.
• Data codes must be unique. A data code may be referenced more than once in the System Definition worksheet, but it must only be defined once in the System Response worksheet.

To enter numerical values for a data code, open the System Response worksheet by clicking the Define Data Codes button on the main input form (see Figure 7). The first row of the worksheet defines data codes for each column of data. The data codes are displayed in red by default as shown in Figure 9.

The first column in the System Response worksheet defines an independent variable. For Frequency Response data, this column will contain a list of frequencies. Its data code is FREQ by default. This identifier is not used by the module. It may be deleted or changed, but it cannot be referenced in the System Definition worksheet.

The remaining columns define the response data codes and their associated values. The number of data entries (i.e., rows) must be equal to the number of frequencies listed in Column 1. There must be at least two rows of data: the Row 1 data code and at least one row of numerical data. All rows except for Row 1 must contain real values.

The response data codes entered in Row 1 must be unique. For example, a data code entered in Column 2 cannot be duplicated or redefined in a subsequent column. However, data codes may be referenced more than once in the System Definition worksheet.

Figure 9. Data code values are defined in the System Response worksheet

To animate the system, press the Calculate button on the main input form. The system inputs will be processed and if there are no errors an ETBX Animation Panel will appear as shown in Figure 10. The Animation Panel animates the dynamic system and provides controls for manipulating the view, such as rotating, panning, and zooming.

Figure 10. Results Animation Window

Figure 11. Calculated results report