In this video, learn to set up appropriate displaced shape plots and control their appearance.
- [Instructor] Displaced shape plots are useful to help visualize the stiffness and load pounds in a component. Animating displaced shapes can further help the visualization. So we're going to right mouse click on results, and choose define displacement plot. The default quantity shown here in display is the displacement magnitude. Now we can change that if we want to, to component displacements in X, Y, and Z, that can be useful at times.
For the moment we're going to stick with just resultant displacement. Now what we're invoking here is a contour plot of displacement, in the same way we had stress plots, this will be a contour plot distributed throughout the structure, showing the value of the displacement. If we actually want to have a deform shape plot, this is the control we have in here, so we can deselect it, or we can select it as we've done in here. Now the automatic scale is probably going to be quite exaggerated, so let's just click on that and see what we get.
Again we've got this highly exaggerated plot, it's too distorted to get any kind of meaning out, and if you show it to a client you're really going to scare them. So we want to go back to the displacement control, we've got a new control created here so we can work on that one. Go back to chart options. And in the definition here, that's the result of the automatic. You can see here, grayed out, there's a scaling factor of 341.
Now it means 341 times the fundamental displacement, our fundamental displacement peak value is round about 5.4 e to the minus three. The automatic value here is somewhat arbitrary, so it's quite often you're going to have to convert that. So if we go to user defined scale, then round about 60 from my estimation, it should give us a reasonable plot. Let's try that. Click that again. And again that's a reasonably deformed plot shape.
We saw previously, if we want to flip between the deformed shape and undeformed, we just check the box here. That's undeformed, and that's deformed. That's the typical amount of displacement we want to see, it's highly exaggerated but we can still see the action of the load case there. So for improved visualization we can also animate this display shape plot. We have two places we can invoke that, we can right mouse click on the plot icon, and we can click animate.
Or, we can click on the plot tools in the command manager region, and there's an animation button there. So let's use that, click animate. And it's buffering five frames, it's completed the buffering. Depending on the speed of your computer, will control how fast that buffering takes place, and then it will play the complete cycle. To make any changes, we need to click the stop button on the playback controls.
And I like to set the number of frames to roughly about 16. Again, if you find that this is really slowing down you machine, you have to set it down 10, eight is kind of acceptable. You can go beyond 16, go, say, to 25, 36, but I think 16's about the optimum. You get the feel for what's going on, and you don't need to kind of overdo it. So 16 would be my recommendation there. Let's play that again. Re-buffers the frames each time.
And it's done that, and we've got a nice smooth animation. Let's zoom in to the little end. You can see very clearly the action, we can see what's happening. Again, these are displacement contours, which are building up here. Now at the moment, our displacement contours are what's called reciprocating. So they're kind of going backwards and forwards. Now it can be a little disconcerting, what we can choose is to just say forward only. If I stop the animation there, then I can change the type to forward only, and we'll see the action there.
So if I replay. Again, buffering the frames. Now I need to click on loop so it keeps doing it continuously. And now it's starting from scratch each time, zero load, and then coming to maximum. That's a little bit fast so let's slow it down.
Now many clients will want to see, okay this is a tensile load being applied, so we're pulling, we're stretching, then we restart the action, pull it again. If we go to the cycling, I quite like that as a representation of the stiffness, but again it can upset clients if they're not used to the idea of the con rod moving the other way, for example. So for just visualization purposes, some people prefer to have this. Again, zero loading, maximum loading. Now we can save this off as an .avi, in that particular case it will buffer and create automatically a corresponding .avi.
Let's stop that for the moment. Now we can also put impose display shape plots onto stress results. At the moment they're onto contour results, so they kind of go together. Displaced shape and the displacements that we're seeing in the contour plot. So to do that, let's come out of here. Go back to the Von Mises stress. Double click, we make that active, so we can see the stress plot again.
Okay, and we've got the deformed results on at the moment, we can switch that off if we want to. Or we can leave it on as a deformed result. What we want to see now is the animation of that displaced shape on the stress results. So we come here, right mouse click, again use chart options, we select the definition tab, again at the moment deformed shape is clicked on here. We've got the user defined control 60, so everything looks good there.
If I just wanted to exaggerate it slightly, let's move it up to say 120 just to see what happens there. Now I can check okay. You can see, again, a more exaggerated deformation. Dependent on your structure, you're going to control this really on the fly. Sometimes we want to see, for example, there's a complicated component, and one bit is moving a lot, but we can't see it, it's a very busy plot, we might set that exaggeration up very high so we can see that very clearly.
So it's a very useful kind of fluid control. Again I can animate this, let's use this method. Buffering the frames. And now we can see the stress contour plot animation with the deformed shape plot. Again, this can be very useful to understand where the stresses are developing, and how the stresses are developing. Gives a good feel for the stiffness and the load paths which are being created. Again, we can save this off as an .avi file if we want to do that.
So let's stop the animation. And we can just exit this model, as we haven't committed any changes into the database. So in conclusion, the deformed shape plot is a very powerful tool. However it usually needs scaling to suit our needs. In the same way the animation tool is extremely powerful, but it needs controlling to give the most effective representation. Probably one of the most common things you are going to be doing is changing from cycling down to forward only, which gives a better picture of the load being applied, and then the load taking off, rather than cycling through reversing the loads.
- Setting up Simulation properties and defined views
- Preparing the geometry
- Setting up a local coordinate system
- Splitting surfaces
- Defining the constraint and the loads
- Running analysis
- Contour control
- XY plots