Transcript
Transcript
Let’s walk through a solution of this topology optimization problem. You can use the controls in the bottom right corner of this video to speed up or slow down as needed. The starter file includes this initial geometry section containing the imported CAD bracket, which was first converted to an implicit design space.The four bolt holes were specified in this CAD face list called restrained faces. Here’s where we’ll create our displacement restraint. Then we’ll do the same for the two loaded faces where we’ll apply a loaded boundary condition. To specify all of the passive faces, or the faces we want to maintain geometrically throughout the process, we concatenate these two lists and call the variable passive faces.Then we’ll move on to create our FE mesh where we’ll first mesh the design space, remesh the surface, and create a volume mesh from our result. After this, we’ll convert to an FE mesh and create our FE model with our FE mesh and a specified material.Next, we’ll define our FE boundaries starting with the loaded faces. We’ll use the Boundary By Body block to select the nodes we specify by thickening the load faces CAD list that we made earlier. We use an Implicit Body From CAD block followed by a Thicken Body Boolean. These two parts together then use the Boundary By Body block to select the nodes in the specified region. Then we’ll use the same process to select our restrained faces.To specify the passive region, or the region around the interfaces that we wish to preserve, we’ll use the same process for the passive faces list. Here, we want to preserve 3 mm of material around the faces, so we’ve created this variable called passive region offset and then multiplied it by two because our Thicken Body block works in both directions and we’ll lose half the thickness in our post processing later on.After defining our boundaries, we’ll move on to create our loading conditions starting with a displacement restraint at their strained faces. All of these inputs are left at zero to allow zero degrees of freedom at these four holes. We then create a boundary condition list where we combine this displacement restraint with a new force of 40,000 Newtons in the positive Z direction on the loaded bases.And now we can move on to specifying the optimization objective. In this case, we want to minimize structural compliance under this loading condition that we’ve created. Next, we’ll apply constraints to our top op. We start with a passive region constraint to maintain the geometry at our specified passive regions and we’ll add a volume fraction response so the top op result is at most 30% of the initial bracket volume. Now input all of our information into a Topology Optimization block and we’ll get the results that we see here.To post process into an implicit body, we’ll use an Implicit Body From Topology Optimization block followed by a Smoothing Body block with a cubic interpolation to make a smooth result from our optimization. Finally, we’ll use the thickened implicits of the passive faces and Boolean union them with our smooth result. And finally, we’ll use a Boolean intersect to ensure that all of the interfaces are the correct geometry and that our new part falls within the initial design region.Now we’ve completed our topology optimization and post-processing of this bracket. Feel free to download the completed nTop file below as a resource.