Applying a Translational Joint Motion
In this section, you’ll apply a translational joint motion to the Rack translational joint. You will apply the motion using the INTERP function, as follows:
Creating a Spline
In this section, you’ll create a spline statement to reference the file and channel arguments from a test performed on a physical model in a test lab. You use the same RPC III file, physical_test.rsp, but you reference data in channel 2.
To create a spline:
1. Click the Elements tab on the Adams View ribbon.
2. From the Data Elements container, click the General Spline tool 
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. The Data Element Create Spline dialog box appears.
3. In the Spline Name text box, enter .suspension.steer_data.
4. Right-click the FIle Name text box, select Browse.
The Select File dialog box appears.
5. Select the file physical_test.rsp.
This file contains physical test data from a test performed on a physical model in a test lab.
6. In the Channel text box, enter 2.
7. Select OK.
Adams View creates a spline that references the physical test data from channel 2 in the RPC III file, physical_test.rsp.
Defining a Translational Joint Motion
Now you’ll apply a translational joint motion to the Rack translational joint, using the INTERP function to reference the spline you created in the previous section.
To define a translational joint motion:
1. Click the Motion tab on the Adams View ribbon.
2. From the Joint Motions container, click the Translational Joint Motion tool 
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. 3. Select Rack_Joint as the translational joint.
Adams View creates a translational joint motion. Next, you will rename the joint motion so that you can easily identify it.
To rename the translational joint motion:
1. From the Model Browser window, click Motions and expand.
2. Right-click MOTION_3, and then select Rename.
The Rename Object dialog box appears.
3. In the New Name text box, enter steer_input.
4. Select OK.
By default, Adams View creates a constant-speed translational joint motion. You want the translational joint motion to vary over time, based on the referenced spline. Therefore, the next step is to modify the translational joint motion so that it varies over time.
To modify the translational joint motion:
1. From the Model Browser window, click Motions and expand.
2. Right-click steer_input, and then select Modify.
The Joint Motion dialog box appears.
3. In the Function (time) text box, select the Function Builder tool 
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.The Adams View Function Builder displays.
4. Delete the existing expression.
5. From the pull-down list of expression types, select Spline.
6. Select Durability Interpolation.
7. Select Assist.
The Interpolation dialog box displays.
8. Enter the following:
■Independent variable: time
■Interpolation Method: Cubic (3)
■Spline Name: steer_data
9. From the Interpolation dialog box, select OK.
10. From the Function Builder, select OK.
11. From the Joint Motion dialog box, select OK.
Note: | If you enter the function incorrectly, you receive an error when you select OK. Check your function syntax carefully. |
Simulating Your Model
Now you will simulate the model to verify that it runs.
To simulate your model:
1. Click the Simulation tab on the Adams View ribbon.
2. From the Simulate container, click the Simulate tool 
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. 3. Set up a simulation with an end time of 5 second and 50 output steps.
4. Select the Simulation Start tool 
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. The model simulates and completes a jounce-rebound followed by a right-hand turn maneuver, and then remains in simulate mode.
5. To return to the initial model configuration, select the Reset tool 
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.Note: | If your simulation fails, check your spline definitions and motion function expressions. For example, make sure that you are referencing channel 2, the spline definition for steer_data. |