Build model Gripper, use dummy

[pogbaminh]

Hello, I'm new beginner use Coppelia. Recently I'm build gripper and motion simulation in Coppelia but it isn't oke. In kinematics of Gripper have revolute and prismatic move, it similar motion of Slider_crank, but i dont connect move prismatic and revolute. When i control joint revolute, Prismatic joint not move as straight line but it move along motion of joint revolute, How i can control it. Thank you.

[coppelia]

Hello,

you need to post a link to your scene file, otherwise it is impossible to unerstand what you are trying to describe.

Cheers

[pogbaminh]

https://drive.google.com/file/d/1TgQJjv ... sp=sharing
Exaxtly, I want to build Slider_crank as picture at link. But when i test set position for joint revolute, prismatic not operate. Can I must write code to control prismatic. Thank you for reply me.

[pogbaminh]

https://drive.google.com/file/d/1_e4g7S ... sp=sharing
I try to build motion of Slider crank but it not motion as I wished, this dummy is not connect each other.

[coppelia]

Please post the scene file.

Cheers

[pogbaminh]

https://drive.google.com/file/d/1T88eou ... sp=sharing
You can check file scene at here. Thank you!!

[coppelia]

You have many problems with that scene. Do following:

• Attach Prismatic_joint to the first Cuboid
• Make sure that there is no self-collision between adjacent links. Work with the local respondable masks. You can visualize collisions from the physics engines in the Simulation dialog
• Add a spherical joint, locate it to the position of the first Dummy, then attach it to the second Cuboid, and then attach Dummy to the spherical joint

Cheers

[pogbaminh]

I can ask why use spherical joint. I watch Gripper model in library also have it but i dont know about it. I read turtorial that spherical joint is combine by 3 revolute joint.

[coppelia]

you could also try to use a revolute joint. However if it is not perfectly aligned, or depending on the physics engine you use, you might end up with an over-constrained system: in a real-world situation, you always have some compliance from various parts, and this is not necessarily the case in a simulation situation.

Cheers