Stress Test

Stress Test

By: Nick Lukin (Design and Manufacturing Engineer) 

Introduction

In order to ensure that the Pathfinder chassis could support the weight of the solar panels in order to properly interface it was necessary to perform a stress/displacement test in Solidworks. The solar panels overall weight was a maximum of 50lbs. The chassis was designed so the panels could sit on top of aluminum standoffs welded to the top plate of the chassis. The force in Newtons was calculated and applied to the standoffs.

 

Figure 1: Stress Test Results

Figure 2: Stress Test Results Continued

 

Analysis

In order to figure out the appropriate force to apply to the model it was necessary to convert the maximum weight of the solar panels into Newtons (1 Newton = 0.2248 lbs). Therefore 50 lbs converts into about 222 Newtons. This number was used for the simulation in order to see how much the maximum weight of the solar panels would affect the chassis. Figures 1 and 2 show the results of the stress test performed in Solidworks. The test results show an exaggerated view of exactly how and where the chassis would begin to deform. It is noticed that the chassis max deformation is about 8.017e+004 von Mises which is very little. The overall characteristics and shape of the deformation is as expected.

Figure 3: Displacement Results

Figure 4: Displacement Results

 

Figures 3 and 4 show the displacement of the chassis and further show how the chassis will be affected by the maximum weight of the solar panels. The displacement results give a millimeter value of exactly how much the metal will move. It is noticed that the top plate bends a maximum of 1.226e-003 mm which is very small (less than a millimeter). This number is acceptable and confirms that the design of the chassis can withstand the maximum weight of the solar panels.

Conclusion

After running the appropriate stress tests in Solidworks it was determined that the design shown in the figures above was strong enough to support the weight of the solar panels. Being that the chassis is the base of the entire pathfinder it must support the weight of everything that is attached to it. The stress tests performed show the strength of the chassis and confirm that the requirement of properly interfacing between the chassis and solar panels is achieved.