Introduction: How to Use Stress Analysis in Autodesk Inventor to Test Your Parts.

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This is an intro to Autodesk Inventors stress analysis feature.  When making parts and assemblies it is extremely important to know where the critical stress and fail points are in your design.  The stress analysis feature removes the guesswork and over engineering in your design.  

The two things needed to start this process is a Inventor Part or Assembly file, and some estimated or actual calculated input forces for your part.

Let's start by opening your Inventor part file.

Step 1: Starting a Stress Analysis

To start a new stress analysis go over to ENVIRONMENTS tab on your ribbon, click on it and on the left side of your screen you will see the stress analysis feature (rainbow colored cube).  Click on the icon and then click on create simulation.  That will bring up a screen of initial settings.  You can choose a static analysis or modal analysis.  

The simple definition of static would be your main input force which is not affected by time/temp/atmospheric pressure.  Modal is dynamic forces (vibration) that will have secondary effects on your part. 

For this trial we are going to use a static stress analysis.  Select it and click OK.

Step 2: Defining Your Parts Material.

Defining what type of material your part is determines the amount and types of forces it can handle before it fails.  This should be the first step before you continue on with your test.  Under your ribbon you will have a materials section with an icon that says ASSIGN, click on this.  It will bring up a pop up window displaying your part material.  If you already defined what the material was when you made your part, that material will be displayed.  If you haven't yet defined it, click on materials and select the desired one.  When you select a material you can also double click on it to see the preset settings for that type if you need to verify or change them.

Once you are happy with your material and settings click OK and then we will be ready to define our constraints and input forces.

Step 3: Constraints for Your Part

Defining constraints for your part is important in order for your analysis to perform correctly.  If I have input forces pushing up on my part, but nothing constrained or held in place to hold the part down, there would be no stress to display.  In this trial I am going to used a fixed constraint the center of my part, which is the middle red cylinder (simulation of steering stem shaft).  This means that this area of my part will remain in place while the input forces are affecting my part.  Use the constraints tools in the ribbon to define them on your part.

Now that this is complete we can move on to input forces.


Step 4: Defining Input Forces

The input forces are what are going to actually be exerted on your part.  These are defined using the LOADS tools in your ribbon.  I am going to add two vertical forces on each of the outer red cylinders (simulated fork tubes).  These loads will be both perpendicular to the top and bottom faces of the clamp for this simulation.  Once I have defined where the load will be exerted the next step is to define the amount of force (magnitude) in Newtons.  For this I am going to use 4448 newtons which is approximately 1000 lbs of force.  

Now that our constraints and input loads are set, we can run our simulation.

Step 5: Run the Stress Analysis

Click on the simulate tab in your ribbon (rainbow colored cube) and the simulation window will pop up.  If you have any errors they will be displayed here.  If there are no errors, click on RUN.

Inventor will run the simulation and show you the different stress types and amounts using the color coded visualization chart.  Anything in RED is bad and changed to your design should be implemented.  


This instructable was just an intro to the stress analysis feature, but there are almost limitless settings allowing you to get the most accurate data possible.  You can import forces from the dynamic simulation feature, see the stress loads in different factors, as well as get a full report under the report icon in your ribbon.  Take some time and familiarize yourself with the aspects of this feature and ensure that your part will do the job intended for it.  

Come check out the Autodesk software at Techshop and start your stress analysis today!