How to make parallel construction stable?
Posted: 21 May 2018, 09:26
Hello!
I have been trying to design a model of this parallel scissor robot:
https://www.youtube.com/watch?v=F7uzU95NOyY (it is genious btw).
I created two pairs of scissors and joint them to plate at the top.
Only pistons at the bottom should be actuated (2 prismatic joints for each scissors pair), all other
joints should just... be (not actuating, but enabling dofs).
I switched all the joints in to dynamic/torque mode.
Weights of all links and plate are about the same - 1~2kg.
I closed loops using dummies - construction is glued in many places - every scissor has
two arms, which must be connected to each other, every arm connects also to the plate at the top.
For dummy connections I used dynamics/overlap mode (I think it is ok?)
This is my scene:
https://drive.google.com/file/d/1ZH-t3_ ... sp=sharing
My problem is that construction is breaking on the joints - it is not standing stable, or even
falling slowly and gracefuly - it just snaps (on the revolute joints in scissor arms).
Why is this happening? And if You can be so kind - is the path I taken to develop this
model a proper path? Or have I made some critical mistake?
I have been trying to design a model of this parallel scissor robot:
https://www.youtube.com/watch?v=F7uzU95NOyY (it is genious btw).
I created two pairs of scissors and joint them to plate at the top.
Only pistons at the bottom should be actuated (2 prismatic joints for each scissors pair), all other
joints should just... be (not actuating, but enabling dofs).
I switched all the joints in to dynamic/torque mode.
Weights of all links and plate are about the same - 1~2kg.
I closed loops using dummies - construction is glued in many places - every scissor has
two arms, which must be connected to each other, every arm connects also to the plate at the top.
For dummy connections I used dynamics/overlap mode (I think it is ok?)
This is my scene:
https://drive.google.com/file/d/1ZH-t3_ ... sp=sharing
My problem is that construction is breaking on the joints - it is not standing stable, or even
falling slowly and gracefuly - it just snaps (on the revolute joints in scissor arms).
Why is this happening? And if You can be so kind - is the path I taken to develop this
model a proper path? Or have I made some critical mistake?