The default Factor of Safety (FOS) plot would show the distribution of values over the entire model with a colour chart. Typically you would modify the colour chart to have the Minimum value as your required FOS. The regions in red are the areas of concern. However depending on the range of the colour chart values, the red colour may be appear on are regions that satisfy the FOS requirement. As you can see in the example below, the red regions could be interpreted as anywhere from 0 to 10. Yet the factor of safety requirement is 3.5.
Suppose you need to make an animation of a 6 degree-of-freedom robot. However you only need to show the end-effector moving from point A to point B to point C, etc. You aren’t concerned with the movement of each joint at the moment.
Have you ever tried free-dragging something with six degrees of freedom? I guarantee you will have it flipping around and inverting due to the fact that there are too many positions and orientations possible. As you are looking at a 2-dimensional screen, the robot could be at any depth; and it’s also possible to satisfy the position with the joints inverted.
So how would you go about animating this robot? You could run some inverse kinematics to determine each joint position required for the desired position of the end-effector, then add motors to each joint, or you could figure out some distance/angle mates that you can control in the animation. But in the end, you just wanted a simple animation showing the end of the arm moving from here to there with all the joints and arms to follow without flipping.
Here is a video showing the steps of how to quickly create an animation with mates to the end-effector at various locations.
We have all used symmetry to boost our simulation times, whether it be planar or cyclic and were happy to have achieved the results in a short time, only to be told by the manager to run the simulation for the full model so it makes more sense to him and to the customers.
Here is a new feature in SolidWorks 2014 which will keep both you and your boss happy. You now have the option to apply the symmetry for the analysis and the software will mirror the results for you and show you the results in the entire model. These new results will actually serve as a double check for the symmetry assumptions that made.
In the PropertyManager of the desired result quantity, under Advanced Options, select Display symmetric results.
Here is a quick look at this feature in action.
In SolidWorks 2013, now you can define sensors which can store transient data from thermal simulations, drop tests, non-linear simulations and dynamics simulation. Due to nature of simulations which support transient data, this new sensor is supported in SolidWorks Simulation Professional and above. The transient sensor replaces the existing response plots which were previously used. Loading of a transient sensor is much faster than response plots since the data is pre-loaded into the sensor.
Reaction moments are only applicable to element with nodes having degrees of freedom in rotation. This is not the case for solids as they only have 3 degrees of freedom per node (3 translations, but no rotation). So how can we get reaction moments on fixed faces of Solid Bodies?
Have you ever tried imposing symmetry for shell elements in SolidWorks Simulation 2012 or older? If you have then you would probably know it is a very tedious process and requires exact knowledge of what the symmetry condition actually does to impose it for shells. The built-in symmetry condition does not work because it requires the symmetry to be applied on a face (which is also the cutting plane), whereas the shells are cut along an edge and not a face. The actual process of imposing this boundary condition was actually published in a previous blog post, “Use of Symmetry in Shell Elements“.
If you tried imposing symmetry boundary condition in SolidWorks 2013, pay close attention to the icon for symmetry plane selection. Did you notice any different between Simulation 2012 and 2013?
When using Shell elements in your Simulation studies it is important to define the offset of your shell to ensure that the geometry accurately represents the 3D model.
The default offset selection in a shell definition is Middle Surface. Therefore the defined thickness will have half of the material on either side of the surface. If you require all of the material on one side or the other, the Top or Bottom surface can be applied. The direction is defined by the orientation of the mesh. If the Top offset was selected, then the material will start from the Top surface of the mesh (part colour) and go below. If the Bottom offset was selected, then the material will start from the Bottom surface of the mesh (orange colour) and be above. Flipping the mesh or adjusting the offset definition may be required.
In SolidWorks 2012 and prior, the orientation was verified after meshing the model by comparing the mesh to the offset setting. New in SolidWorks 2013 is the ability to render the thickness in 3D to graphically see if the offset is correct. Please watch the following video to see this new functionality.
Imagine a manhole cover in a pressure vessel that needs to be bolted to a flange in the pressure vessel. This usually requires a number of bolts to hold the two pieces together. Furthermore, same type of bolts may be present in the assembly at various locations. Imagine having to define all these bolt connectors for a simulation. I am sure this is going to give nightmares to people trying to simulate multiple bolts using SolidWorks Simulation.
You will be happy to learn that SolidWorks Simulation has a smart feature which could reduce the effort in the definition of these bolt connectors.
SolidWorks simulation provides two options to solve the set of FEA algebraic equations; iterative or direct solution methods.
The iterative solver, FFEPlus, uses approximate techniques to solve the problem. It assumes a solution and then calculates the associated errors. The iterations continue until the errors become acceptable.
The direct solver, Direct Sparse, solves the set of equations directly without any approximations and hence there are no errors associated with the solution process. There will still be discretization errors which are present both in iterative or direct solvers.
A solver may be selected changing the study properties from the study feature tree. Read More »
My SolidWorks Simulation 2013 pick of the day is the new functionality for obtaining beam joint reactions. Now it is possible to list reaction forces and reaction moments at beam joints that have fixed translations or rotations.
After the simulation is completed, right click on Results and choose the List Result Forces. Now you can pick the joints you want to view the reaction forces on. The reaction forces and moments will be displayed in call outs on the screen with a graphical representation on the joint.
Watch the video below to see this feature in action.