Inventor Chain

[crazyStone]

I am pretty fluent with Autodesk Inventor, however I have been wondering for some time how to make functional (realistic) chain? I can produce the chain with in an assembly with design accelerator but that only produces a set of sprockets and a blue line simulating the roller chain. Any help would be greatly appreciated.

[msimon785]

This topic has burdened Inventor users in FIRST for years. Short verdict: its possible, but it would lag your assembly more than anyone could possible stand, and as such, its not worth it.
The only way to really create chain in Inventor is to CAD a model of the pin, side plate (outer), side plate (inner) and retainer. After doing this, Constrain, Constrain, Constrain. The only possible way of achieving the effect is by calculating the EXACT number of links, and creating an assembly in which the links follow the correct path. Two circular figures (comparable to the sprockets) must be inserted into the subassembly and made invisible. You'll need to set several parameters, and eventually insert it into the main assembly as a dynamic part.
This will make your assembly unusable due to the lag time and is only really effective as a visual phenomenon to be displayed on its own, not in a robot assembly.

Creating a chain/sprocket system using the Chain Generator will probably suit you much better. While you may be deterred by the horrendously ugly blue belt, as I was, it can be improved upon. By opening it up in part view, you can change the material top "Metal- Steel (Oxidized)", which looks not very much unlike real chain. Make sure, however, to make the Design Accelerator either flexible or dynamic. You may also choose to right click the Accelerator in the tree, and un-check "Calculate". This would be preferable if upon initial creation of the chain, it errors saying that the path cannot be calculated.

Good Luck!
Feel free to email me at msimon@msedesign.netfor any Inventor help!

[Jeff 801]

If by functional you mean you can rotate it and make it run like the chain would in real life then no. If you want it to look good and not move then yes.

The way described by msimon785 is good but it has a few extra steps from how I have done it. What I do is I make 2 complete links and inside and outside link. From there if the chain run will be straight I do a component pattern to reduce the number of constraints I have to do. For runs that are curves I do an insert constraints on every link so instead of needing 2 constraints for each link its only one. I have uploaded my models of the links for #25 if you need/ want #35 I have that as well.

[RyanCahoon]

This looks like an extension of [Jeff 801]'s method that supports arbitrary chain paths, and includes a bit of animation.

I'm not an expert at Inventor Studio, but I suspect the chain animation only work via the Studio environment; in the modeling environment, you would get the sprockets' turning linked (which you could do with the chain design accelerator), but the chain links wouldn't move with them. By ensuring that the sprocket teeth interface with the chain links appropriately, you could probably get a similar effect by turning on the contact solver, but if you try to run contact solver on an entire robot model, I suspect the responsiveness of your model would suffer greatly (as has been stated).

--Ryan

[crazyStone]

Thank you for the responses, I had suspected the limitations you explained but had hoped I would be wrong. I think Inventor Studio is probably the only way to truly simulate the chain in its entirety but at that point it would crash my laptop. Thanks again, the chain is being used in a possible, 2 speed switching drivetrain. Credit to Team 148, its their switching drivetrain with a 2 speed gearbox integrated into the module.

[crazyStone]

This is a little later then I had hoped, but this is a rough animation of the design that we are persuing. Credit to 148 for the switching module idea, Thanks for letting us see it in st. louis!!!


http://www.youtube.com/watch?v=QQvVz6dWOYU

[MoHottaMoBetta]

Our team modelers discovered a silent video tutorial on YouTube that shows the process of making a chain that you can animate. They had a few hassles making it fit our specific needs but they got the bulk of it down.

Check out http://www.youtube.com/watch?v=DiBGYdbBPHo and see if it is what you wanted.