Event simulation not working as expected

ryantheengineer — Sun, 15 Oct 2017 04:58:14 GMT

I'm exploring event simulation for a soft pneumatic robot actuator. I've done some linear static simulations and those have worked fine, meaning the actuator expands somewhat on one side, forcing a bending motion. I want to validate this in event simulation, as well as determine some force outputs by adding a plate and determining reaction forces. The thing is, I haven't been able to get nearly the kind of displacement in event simulation for the same model, loads, and material done in static stress simulation. That doesn't make sense to me. I've attached a screenshot of what the event simulation spits out (not including the plate).

I used the generate global contacts option, but the only constraint I applied was on the base of the actuator. I think the only generated contact was a separation contact. In every static stress simulation this has worked fine, so I'm a little stumped. I've attached a picture of the output of the event simulation just for context. Any advice would be much appreciated.

Re: Event simulation not working as expected

innovatenate — Mon, 16 Oct 2017 18:39:40 GMT

You don't have to add components to the design and have contacts. You can enable Reaction Forces in the Result Output in the Simulation Settings.

One thing to consider in Event Simulation is that you are simulating for a given time period, the default time period is 1 millisecond.

If you look at the Solver Output, see Results > Solver Data:

You can review various energy types to determine the state of your design. Remember that a Static Stress analysis is not time dependent like a Event Simulation, so it's very different.

>>>>> Writing FEMAP output for time = 0 <<<<<<<

           Time   Procedure    Total    Kinetic   Internal  Viscous   External   Total    Elapsed     Remaining
    Inc    Step     Time       Time     Energy    Energy    Energy     Work      Energy   Wall Time   Wall Time
      0  4.16e-06  0.00e+00  0.00e+00  0.00e+00  0.00e+00  0.00e+00  0.00e+00  0.00e+00  0 00:00:00         n/a
>>>>>> Writing FEMAP output for time = 0.000102745 <<<<<<<
     50  3.57e-06  1.94e-04  1.94e-04  1.98e+00  8.17e-01  2.33e-03  2.79e+00  7.37e-03  0 00:00:00  0 00:00:01
>>>>>> Writing FEMAP output for time = 0.000201368 <<<<<<<
>>>>>> Writing FEMAP output for time = 0.000301933 <<<<<<<
    100  3.78e-06  3.82e-04  3.82e-04  1.85e+00  9.44e-01  1.30e-03  2.79e+00  4.98e-03  0 00:00:00  0 00:00:01
>>>>>> Writing FEMAP output for time = 0.00040072 <<<<<<<
>>>>>> Writing FEMAP output for time = 0.000503194 <<<<<<<
    150  3.92e-06  5.73e-04  5.73e-04  1.87e+00  9.30e-01  8.86e-04  2.79e+00  3.80e-03  0 00:00:01  0 00:00:01
>>>>>> Writing FEMAP output for time = 0.000600451 <<<<<<<
>>>>>> Writing FEMAP output for time = 0.000701788 <<<<<<<
    200  3.95e-06  7.70e-04  7.70e-04  1.79e+00  1.00e+00  6.58e-04  2.79e+00  3.06e-03  0 00:00:02  0 00:00:00
>>>>>> Writing FEMAP output for time = 0.000801197 <<<<<<<
>>>>>> Writing FEMAP output for time = 0.000903719 <<<<<<<
    250  3.85e-06  9.62e-04  9.62e-04  1.79e+00  1.01e+00  4.58e-04  2.79e+00  2.60e-03  0 00:00:02  0 00:00:00
>>>>>> Writing FEMAP output for time = 0.00100046 <<<<<<<
    260  3.89e-06  1.00e-03  1.00e-03  1.80e+00  9.96e-01  4.08e-04  2.79e+00  2.57e-03  0 00:00:02  0 00:00:00

Total Wall clock Time for the Analysis:      4.288 (seconds) = 0 00:00:04 (dd hh::mm::ss)
Total CPU Time for the Analysis:             34.31 (seconds) = 0 00:00:34 (dd hh::mm::ss)

There's a discussion in the below forum post that may be helpful to review.

https://forums.autodesk.com/t5/fusion-360-support/event-simulation-for-vertical-load-test/td-p/7055526

I hope that helps!

topic Event simulation not working as expected in Fusion Support Forum

Event simulation not working as expected

Re: Event simulation not working as expected