Is there a method to prevent trains in the middle carriages from derailing?

[EnzoFriend002]

Greetings.
Recently, I am developing a train system which consists of 4 cars. The current issue is that the middle carriages are always toppling and shaking, which causes derailment when the train is moving, no matter straight line or horizontal curves.
In the connections of the carriages, each carriage is connected with a Rod Constraint, whereas all carriages consist of their individual collision group, which have no collision between carriages, so it’s not about the carriage collision problem.
Hence, the train is moved by a “for” Loop that uses the Cframe vector of the front carriage(clarify by the direction) and moves by the main part of the train using AssemblyLinearVelocity.

How should I solve the middle carriage problems?

[computerph1_DEV]

i also got the same problem, but for the movement i used line velocity and runservice. i fixed my issue by debugging collisions, you can toggle it inside of the gear icon in the top right of the viewport. i think its called toggle collision surfaces

also #help-and-feedback:scripting-support

[EnzoFriend002]

Actually what I have done in the collision is the same as you mentioned.

[computerph1_DEV]

also a tip: for decorative or complex unions near the rails, turn off its collisions, (it will help with performance and also may fix some derailing issues)