Hi
I am trying to make a McPherson strut using A2+, but encountered wired problem with moving parts.
Error "animation problem detected" appears in positions where whole model should behave quite stable (nothing "strained", all angles looks good etc.)
Model contain "armRF" constrained to fixed rotation axis (FixCylinder) and spherical to "KnuckleRF-asm" on the other side.
Knuckle (green part - in fact knuckle and bottom of shock absorber in one part) is constrained spherical to "SteeringRod" and axially coincident to "ShockTopRF".
SteeringRod (yellow on model) is spherically connected on both ends between fixed mounting point (FixSphere_001) and knuckle.
"ShockTopRE" (top grey part of shock absorber) is spherically connected to fixed |FixSphere_002) on top.
All files included - A2+ assembly is in file frontAsm.FCStd, in two other FCStd are models used in assembly.
Also I attached few pictures of assembly and tree.
And in general model works, can be solved resulting proper alignment of all parts with message:
Code: Select all
===== Start Solving System ======
20:20:35
20:20:35 convergency-conter: 151
20:20:35 Calculation stopped, no convergency anymore!
20:20:35 TARGET POS-ACCURACY :0.0001
20:20:35 REACHED POS-ACCURACY :0.00013470727165820507
20:20:35 TARGET SPIN-ACCURACY :0.0001
20:20:35 REACHED SPIN-ACCURACY :9.659346157805867e-06
20:20:35 SA SPIN-ACCURACY :0.00021294593556323688
20:20:35 ===== System solved using partial + recursive unfixing =====
But when trying to animate it, in positions where lower arm is closer to horizontal positions, everything starts to broke apart, with an message "animation problem detected", that happen every time when reaching similar position of model. When "animation problem detected" appears, I can still click on "solve constrains" and it works, but still can move model in that direction.
But is works quite well in position where lower arm is nearly vertical.
Positions where problem occurs not seem to be complicated - nothing is strained, all angles looks sane, so have no idea why.
Any advice how to handle such issue?
Is this possible to run solver in more verbose mode, to be able to understand/debug such problem by myself?
Thanks
- mcpherson.jpg (143.53 KiB) Viewed 12103 times
A2plus V0.4.47e
OS: Ubuntu 20.04.1 LTS (ubuntu:GNOME/ubuntu)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.23058 (Git)
Build type: Release
Branch: master
Hash: 6e60870ebcb2df018adb7a1281c00dde87750f11
Python version: 3.8.6
Qt version: 5.12.5
Coin version: 4.0.0
OCC version: 7.4.0
Locale: English/United States (en_US)