Passive Joint setting and joint connection

[huiduan-25]

Hello,

Hope everyone had a great weekend.

I am wondering how to set a passive joint in a four bar linkage mechanism? Should I just don‘t set anything in device of HingeJoint?
Also, from the picture I attached, I am not sure how to connect the 5th joint. The shape of the selected part has been used in the 3th joint, and if I select it again, there will be two of the part? How should I solve that?

Thank you!

[huiduan-25]

I set a SolidReference node at the endpoint of the 5th joint, it works. But 2,3,4,5 joint are fixed and does not rotate any more.

[ad-daniel]

Are you sure all Solids/links present have a Physics node set?

[huiduan-25]

Hello Daniel,

I think all links have physics node set, including boundayObject and physics. I named each part and selected one for the SolidReference . I found no matter which part I select, the part will fixed. Do you know how should I solve it?

Thanks

[ad-daniel]

A similar closed-loop structure is available in the file > open sample world > coupled_motors.wbt, you can look at it for inspiration. Concerning your problem, it's hard to say without the world file. Can you provide your project?

[huiduan-25]

testleg5.zip
Hi daniel,

I have attached my project file.

[huiduan-25]

Hi, Daniel

I have found the solution of problem. Some of the axis of the joint were set incorrectly.

Thank you!