Constraint Issue

[MB2011SD]

I was putting together an assembly. Imagine a plate that has (2) different rollers. and each roller, is inserted into a guide-track. The track is straight, but at the end, it takes a radial turn. (Each roller has it's own specific track, so there are two tracks in total. each track is straight, then has a radial curve at one end)
I want both rollers to follow the turns when the plate with the rollers is pulled as a unit, down the tracks.

I tried using this constraint: Tangent to keep the roller inside the track and it works, up until the track goes from being straight, to having a curve.

On my drawing, the "roller", just looks like a circle that has been extruded. the "track" is just a pocket, that looks like a slot, except the slot is straight in the beginning, then takes a turn.

So in a way, this plate moves like a "slider", except the slots are not perfectly straight.

Does anyone have any advice on how to make this work, or what kind of constraints to use, to connect the plate with rollers to the entire track?

My goal is to use "mechanism" or animation to move the plate down the tracks eventually.

Also note: If I only focus on the curved side of the track, I can make the part "work" there, but when i move the part towards the straight part of the guide track, then it stops. the tangent constraint keeps the part on the curved surface but won't let me transfer it to the straight surface...

any help or advice is appreciated.



Edited by: MB2011SD

 

[kenppy]

I'm not in a position to check this right now but I think that the track needs to be made with one curve, not a straight followed by a curve. Copy this track and pastre as approximate to get a single curve.

 

[Kaz Z06]

The easiest thing to do is create slot jointsyour rollers can use to follow the track. Make two datum curves that will represent the path the center of each roller will take as it moves from the straight part to the curved portion. Place a datum point at the center of each roller and create the slot joint. You won't capture the kinematic/dynamic behavior the rollers will go through in contact with your plate/roller surface, but the motion will be correct. 3D contact may allow you to model the actual parts, but this may be challenging for MDO to handle (rollers moving around a corner).

 

[MB2011SD]

Thank you. I found an assembly someone else did where I work, and I noticed he did exactly what (Kaz Z06) said, to do. What I am doing now is trying to emulate what he did. Thanks very much though for responding. It sounds like you knew exactly what I was trying to do.