Andron Handling uses Altair SimSolid™ to design Bespoke Handling Equipment
SimSolid’s unique technology totally eliminates geometry simplification and meshing: the two most time-consuming, expertise extensive and error-prone tasks done in traditional structural analysis.
Andron Handling developed a bespoke handler for a major automotive supplier. The handler transfers wheel sets from a conveyor system to delivery pallets with tight space constraints. A pneumatic clamping system is used to grip up to four wheels at a time, allowing rotation of the wheels while clamped.
We needed to assess the strength of the welded fabrication and vertical clamping arms for both lifting and clamping loads. In previous analysis of this type we would have removed the wheels from the model and applied reaction forces at the bottom of each of the clamp arms. In this case we used a different method that would not have been practical using traditional FEA.
Using SimSolid the complete assembly can be analysed. As shown in the figure 1 below, clamping forces are accurately simulated by applying a force to each of the four piston rods and a matching reaction to each cylinder body. Sliding connections are applied to the piston and linear bearings to allow this force to be transferred to rigid bodies simulating the wheels.
The analysis can be completed without needing to simplify the CAD model, saving significant time. Even small components such as circlips and fasteners can be left in the analysis model.
Reaction forces at the lifting eye are shown in figure 2, these are within 1.5% of theoretical weight calculated in SolidWorks. Note that the figure in SimSolid is likely to be more accurate as exact weights have been applied to certian items, e.g. linear bearings and cylinders.
The image below shows the predicted displacements due to gravity. The full assembly had 530 parts, with a simulation time of less than 50 seconds. This speed allows us to run multiple design iterations in the budgeted time.
Below is a detail view of the stress results in the clamping arms. Stress values were found to be well within limits, giving a predicted safety factor of over 8 against yield.
Finally, below is an animation of the sliding deformation with the stresses overlaid.