A2plus circular edge constraint

[adcnc]

using:
OS: Linux Mint 20.1 (X-Cinnamon/cinnamon)
Word size of OS: 64-bit
Word size of FreeCAD: 64-bit
Version: 0.19.24267 (Git) AppImage
Build type: Release
Branch: master
Hash: b2ca86d8d72b636011a73394bf9bcdedb3b109b7
Python version: 3.8.6
Qt version: 5.12.5
Coin version: 4.0.0
OCC version: 7.4.0
Locale: Dutch/Netherlands (nl_NL)

A2plus V0.4.53

the carriage jumps from the rail if I try moving it. Using <circular edge constraint>
If I make a new drawing with only the rail (fixed) then it works O.K.
Tried it several times.

this works, I can shift the carriage


with the fixed U-beam the carriage jumped from the rial

[Kunda1]

Moved to Assembly subforum

[kbwbe]

with the fixed U-beam the carriage jumped from the rial

Hi,
i can confirm this behaviour. The reason is, that trying to move the slider with the a2p simulation tool, the a2p solver switches to a special simulation mode, where all parts are moved at once. This mode does not work very well with chained constraints. In this case here the calculation is completely instable and fails to work. Where as static solving is working fine. (This mode solves the assembly step for step beginning with a fixed part)

There are two workarounds:

a)
- Place the fixed frame part
- constraint the rail completely to the frame
- after that, set the property "fixedPosition" of the rail to true.
- constraint the slider to the rail
- now you should be able to move the slider by simulation button

b)
- Place the fixed frame
- constraint the rail completely to the frame
- constraint the slider to the rail
- move the slider by using the transform tool of FC
- solve manually when needed.

[adcnc]

thanks for the time taken, a late response I reinstalled linux + FreeCAD and got some problems with GRUB. but the problem is in A2plus, luckily there is a solution. I have copied your solution
Everything works now.