Getting Started > Getting Started: Adams Vibration > Getting Started Using Adams Vibration > Building the Model > Creating Input Channels

Creating Input Channels

Here you create two input channels at the center of the payload adapter (in the global x and y directions) and create vibration actuators for them.
Input channels provide ports into your system that you can use to:
■Plot the frequency response.
■Drive (vibrate) your system using a vibration actuator.
A vibration actuator applies force input or a displacement, velocity, or acceleration to vibrate the system.
A typical design specification may call for an input acceleration level of 0.2 g2/Hz when applied as a PSD. For this problem, we will use an equivalent force input normalized to a value of 1, since we are only interested in the relative accelerations at various frequencies.
You will create two vibration actuators that apply two orthogonal input forces that drive the system with sine waves over the range of specified frequencies. The y input will drive the satellite in the vertical direction. The x input will drive the satellite laterally.
Then, you will create a third actuator that applies a 1g vertical acceleration in the y-direction.
Finally, you will review the vibration actuator.

To create input channels and vibration actuators:

1. Click the Plugins tab on the Adams View ribbon.
2. From the Vibration container, click Vibration tool → Build → Input Channel → New.
3. In the Input Channel Name text box, enter .satellite.input_x.
4. Leave the default Force.
5. Right-click the Input Marker text box, point to Marker, and then select Browse.
The Database Navigator appears.
6. Double-click payload_adapter.reference_point.
Adams Vibration inserts this marker into the Input Marker text box.
7. Select Translational.
8. Set the Force Direction to Global X.
9. Select Actuator Parameters.
10.  Select Swept Sine.
11.  In the Force Magnitude text box, enter 1.
12.  In the Phase Angle (deg) text box, enter 0.
13.  Select Apply.
Adams Vibration creates the input channel and vibration actuator, and leaves the dialog box open so you can create the second input channel and vibration actuator.
14.  To create another input channel, in the Input Channel Name text box, enter .satellite.input_y.
15.  Leave the default Force.
16.  In the Input Marker text box, leave payload_adapter.reference_point.
17.  Set Force Direction to Global Y.
18.  Select Swept Sine.
19.  In the Force Magnitude text box, enter 1.
20.  In the Phase Angle (deg) text box, enter 0.
21.  Select OK.
Adams Vibration creates another input channel and vibration actuator.

To create a kinematic input channel and vibration actuator:

1. Click the Plugins tab on the Adams View ribbon.
2. From the Vibration container, click Vibration tool → Build → Input Channel → New.
3. In the Input Channel Name text box, enter .satellite.input_accel_y.
4. Set Force to Kinematic.
5. Right-click the Input Marker text box, point to Marker, and then select Browse.
The Database Navigator appears.
6. Double-click payload_adapter.reference_point.
Adams Vibration inserts this marker into the Input Marker text box.
7. Select Global.
8. Select Translational.
9. Select Acceleration and Y.
10.  Select Swept Sine.
11.  In Magnitude text box, enter 9806.65.
12.  In the Phase Angle (deg) text box, enter 0.
13.  Select OK.
Adams Vibration creates another input channel and vibration actuator.

To review the vibration actuator:

14. Click the Plugins tab on the Adams View ribbon.
1. From the Vibration container, click Vibration tool → Build → Input Channel → Modify.
The Database Navigator appears.
2. Double-click the model name to display the list of input channels.
3. Double-click .satellite.input_accel_y.
4. Select Plot Actuator to open the Actuator Preview Plot dialog box.
5. Specify the following:
Begin: 0.1
End: 100
Steps: 1000
6. Leave all other default settings.
7. Select Generate Plot to plot the actuator.
8. Close the Actuator Preview Plot dialog box.
9. In the Modify Vibration Input Channel dialog box, select OK.