Description:
"Integrate" tool returns ~-0.5x the correct value for a node-selection sum of "reaction forces"
Version:
FEBio V4.12; FEBio Studio 3.1
Steps To Reproduce:
Open the attached model (over-braced cantilever beam, prescribed-displacement/rotation BCs at two clamped ends, a surface traction load on the free end) and solve.
In PostView, go to Mesh > Node Sets, right-click the node set at one of the clamped ends (85 nodes in this case), and choose Select Nodes.
Set the active data field to Y - reaction forces.
Open Post > Integrate. Note the displayed running-sum value at the final time step (t = 1).
Separately, open Post > New Graph (or equivalent "Node Graph") for the same selection and same field, across all time steps. Export/save this raw per-node time history (Save button).
Manually sum the per-node columns in the exported Node Graph data at t = 1 and compare to the value read off the Integrate window in step 4.
Root Cause found and corrected. See document: IntegrateNodes_fix.diff
Integrate Bug Test Files.zip
Description:
"Integrate" tool returns ~-0.5x the correct value for a node-selection sum of "reaction forces"
Version:
FEBio V4.12; FEBio Studio 3.1
Steps To Reproduce:
Open the attached model (over-braced cantilever beam, prescribed-displacement/rotation BCs at two clamped ends, a surface traction load on the free end) and solve.
In PostView, go to Mesh > Node Sets, right-click the node set at one of the clamped ends (85 nodes in this case), and choose Select Nodes.
Set the active data field to Y - reaction forces.
Open Post > Integrate. Note the displayed running-sum value at the final time step (t = 1).
Separately, open Post > New Graph (or equivalent "Node Graph") for the same selection and same field, across all time steps. Export/save this raw per-node time history (Save button).
Manually sum the per-node columns in the exported Node Graph data at t = 1 and compare to the value read off the Integrate window in step 4.
Root Cause found and corrected. See document: IntegrateNodes_fix.diff
Integrate Bug Test Files.zip