Optimize Spring in Mechanism with BMX

[SK_13639906]

Hello. I am simulating one beam model which rotates around an axis.

・A clock spring is set on the rotation axis.

・In MDO, beam model start to rotates upward once it start running

I would like to explore Minimum Spring Constant K (Nmm/deg)  that allows the beam model to rotate more than 40 degrees.

(no need to change Beam model dimension)

In this case, is it possible to obtain a solution for the spring constant K with BMX?

Or any other solution in Creo?

I try setting Spring constant K as BMX Goal by using relation. But it was not explored

This problem will be solved by hand calculations. However If a solution exists for this simple problem, I will apply the method to more complex problems . (to simulate Car Seat Tumble Motion)

Any advice would be greatly appreciated.

[Catalina]

Hi @SK_13639906 

Thank you for your question. 

Your post appears well documented but has not yet received any response. I am replying to raise awareness. Hopefully, another community member will be able to help.

Also, feel free to add any additional information you think might be relevant. 

Best regards,

[Lewis_Maina_M]

Hello, I am not sure which calculation you are performing but I will use an example to guide you on how to use BMX to get minimum K value for the Torsion Spring

STEP 1:

Create a parameter called SPRING_K and assign it a random value 

STEP 2:

Create Torsion spring and assign parameter created to K factor i.e #SPRING_K

STEP 3 :Create a measure of twist angle  and run static analysis ensuring gravity is enabled and material properties assigned to the part

I will use BMX to determine K value which  will make twist angle to be -5 degrees (your case might be -40 or 40)

STEP 4:

Save mechanism and playbacks , open Analysis and create motion analysis. Create parameters . you should get MIN and MX parameters of mechanism measures

STEP 5 : Run feasibility analysis (you might need sensitivity analysis depending on complexity of the design). Add Your constraint (mine is -5 degrees) and Variable SPRING_K parameter (The one we used in the mechanism)

Results: Analysis will change the parameter until your goal is met

Validate Results by running Mechanism again:

Hope this helps.

 For more details watch this video:

https://youtu.be/I6-gE-WHZpE