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1-Visitor
June 21, 2012
Question

Loadcell Reaction Over Time (Force Balance Over Time)

  • June 21, 2012
  • 3 replies
  • 1693 views

I have a 4 bar linkage w/ a torque applied at one connection point (defined elsewhere in the mechanism). I would like to know the max force reacted on another surface (or point) at the output of the linkage.


I'm able to use a Loadcell Reaction measure (via Force Balance Analysis). I'm unable to figure how to do this over time (or duing the stroke of the mechanism).


Anyone have some pointers. I feel like this has to be possible.


Thanks,
Dan


3 replies

16-Pearl
June 21, 2012
Dan,

Run your analysis as "Dynamic" and create a measure at the joint location you wish to capture the reaction at.

Regards,

Chris

Christopher Kaswer
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dhershey1-VisitorAuthor
1-Visitor
June 21, 2012

Hi Chris,


Thanks for responding. So, I have Radial Force Measures at each of the hinge points in the linkage.


However, I’m actually looking for the max force output achievable on a non-hinge surface. The sketch below is similar to what I’m looking for. It’s obviously quite simplified.


Thanks again,


Dan

1-Visitor
June 22, 2012
Dan,

You will only be able to extract reaction loads at joints. Otherwise the bodies (in between joints) are considered "rigid" and do not provide forces internal to the body. You must break the body into two bodies and place a joint at the point you want to extract the force from. Otherwise your only data available for a body point is position, velocity, and acceleration. Your new joint can be a weld joint, which will not allow movement, but will allow you to extract a force.

Randy Speed
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