Help setting up static and nonlinear static stress simulation in Fusion360 simulation.

[frederiksoe]

Hi all, 

I hope you all had a great new year! 

I'm currently developing a foldable backrest for a cargo bike, and therefore I'm trying to validate if the construction is strong enough. 
I'm new to the simulation environment and I'm not sure how to set constraints and contacts right.

The backrest is attached with two custom "aluminum shaft clamps" to the rack of the cargo bike and allows the backrest tube to pivot with self-lubricating bushings, a cam lever, and two custom "aluminum pivot arms". The backrest is a Ø25x2mm aluminum tube. 
The right alloys are still unknown, so right now the custom CNC parts are in 6061 and the hardware is in default steel. 

I don't know the right forces that a passenger would affect the backrest with, but I have tried to run a test with 300N/30kg. 

I would really appreciate it if somebody could help me with some guidance regarding mesh setting, constraints, and contacts. 

Best, 
Frederik Sølver 

[TheCADWhisperer]

Are there any unresolved issues highlighted in your Timeline?

My recommendation would be to resolve modeling issues before attempting to tackle a complex higher level subject like analysis.

Fully define each and every sketch.

Move is almost always the wrong move (pun intended) as used by beginners.

Ask questions early and ask questions often.

Is this a school assignment (OK if it is)?

[frederiksoe]

Hi CadWhisperer, Thanks for your reply. 
Sorry for uploading a project with a lot of errors and non-constrained sketches. I have another project with the whole assembly (almost no errors.) 
This is meant for a new product for the company I work at. Unfortunately, I'm not an engineer, so I'm not skilled with simulations of this kind. 
I think the documentation available for Fusion360 Simulation is terribly explained, and therefore I find it really hard to figure out how to set contacts right. I can see that the model is fully constrained with no DOF, but I'm not sure that my result is correct after running the simulation. 

[frederiksoe]

Hi CadWhisperer, Thanks for your reply. 
Sorry for uploading a project with a lot of errors and non-constrained sketches. I have another project with the whole assembly (almost no errors.) 
This is meant for a new product for the company I work at. Unfortunately, I'm not an engineer, so I'm not skilled with simulations of this kind. 
I think the documentation available for Fusion360 Simulation is terribly explained, and therefore I find it really hard to figure out how to set contacts right. I can see that the model is fully constrained with no DOF, but I'm not sure that my result is correct after running the simulation. 

[wersy]

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@frederiksoe  schrieb:

I'm not an engineer, so I'm not skilled with simulations of this kind.

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In order to carry out FEM stress simulations, it is important to have extensive knowledge of static calculations. Only then will you be able to apply the contacts correctly and assess whether the results are realistic.

This means that you should also be able to calculate the loads in the conventional way. FEM is a method that calculates the loads in detail at every point of a component and thus also helps to optimise a component.