Modeling of Spring Damper with Preload values in a System

[struclearner]

In ADAMS View, when a Spring Damper with pre load value is defined, the compression of the spring increases the spring force from pre load to a value depending upon the compression of the spring, while the extension of the spring decreases the pre load value.
When the parts joined by a spring with a pre load value defined, move towards each other, the spring force increases.
When the parts joined by a spring with pre load value move away from each other, the spring force decreases.
Is there any way to get the spring force increase during the extension stroke as well?
I am simulating a mechanism with two hydraulic actuators with initial static pressure which are pre load values for the springs modeling the hydraulic cylinders, the pressure of the system increases to overcome the resistance, during the extension and retraction strokes of the cylinders.
The objective is to determine the forces on the supporting structure during the strokes of the actuators.
Thanks for your help.

 

[GregLocock]

Draw a graph of your desired system characteristic (force vs length) and I'll show you what to do.



Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

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[struclearner]

Hello Greg,
Attached slide shows the Force vs Displacement graph for two springs going into extension and compression used in a mechanism with two actuators, one is going into extension while other is going into retraction, in both actuators, there is pressure rise at the end of their respective strokes.
There might be a way in ADAMS View to set the stretched spring to get the force increased in addition to the spring pre load value defined.

 

[GregLocock]

Terminology hint - don't call it preload! Easiest way is a non linear spring using a spline. Slightly less easy is to write an SFORCE equation using IF or STEP5. Most difficult is to set up a contacting spring arrangement.

Cheers

Greg Locock


New here? Try reading these, they might help FAQ731-376

http://eng-tips.com/market.cfm?