Flexible Cable

[Deadwood]

I've looked and nobody seems to know how to do this.

 

I want to create a flexible cable...one that can be wrapped around whatever I want like a pulley or just a round rod then apply a pulling force to it to lift or actuate something.

 

I'm protective of showing my designs...so here's a sample we can work on that approximates the purpose of a flexible cable....the right side of the cable will be the side of the pulling force.

Don't read too much into this pic...it's just for demonstration purposes.

 

[Devented]

I to had questions about Flexible Wiring...

http://www.cadtutor.net/forum/showthread.php?t=35529

Here's my post, and the tips I got.

Only one person tried to help me out...

Good Luck man.

[shift1313]

After I saw your post(and after Devented posted his question) i played around with this a little more.

 

In relation to your question deadwood, the only power transmission setup I was able to create was either a belt or chain(endless). I was using inventor 2010 and you are able to create flexible parts which alter based on other components in an assembly but I do not think it would work in the manner you intend. Im really interested in figuring this out but unfortunately I just have never done that before.

 

Does your rope setup need to be a fixed length or can it be an endless closed section?

 

Devented, i was looking through some of the "help" that IV2010 has, and one of the flexible hose helps is an excavation arm with hydraulic lines on it very similar to what you were trying to create. I was playing some last night and this morning but unfortunately I dont think i will have any time to mess with this for another week or two since I will be on vacation.

[Deadwood]

My setup requires a fixed length open end cable.

 

I did think about and open end chain...I know I can drive an insert constraint at the links but I'm not sure if I can apply a sliding joint to the whole chain so it will move along the pulley/pivots.

 

Others on other sites have asked this question and the thread just got dropped....can't Inventor do this?....I'm sure someone has designed a cable with a force applied to it to move a mechanism...just designing a bike with a gear shifter would accomplish this.

 

 

Devented.....I think I found a solution to your problem....I'm pissed cause I lost what I originally typed cause of the post limit before posting links...ahhhh!

 

Anyway, here's the long way....go to Autodesk.com discussion groups under Inventor...type "Flexible cable" in the search box to the right....scroll down to "Fixing the length of a conformable cable or hydraulic hose"....in there, scroll down to user dan_inv09...he provides a file named arm.zip....open up arm_assembly1.iam and look for the part named arm2...you'll have to extract or save to Inventor...under it there is an angle constraint named Drive this angle...drive this constraint and you'll see how the cable/hose keeps it's length and flexes as the arm bends in...if this will work for you, you'll have to figure out how to mimic it...I know I'm not at this level yet, lol....hope you understood all that.

[shift1313]

I can certainly see where this would be helpful to have. I know you can apply a dynamic force which may be able to mimic what you are trying to do while creating a flexible part that would "look" like a cable but this solution wouldnt provide you with the data you want (i dont think). Im going to put this on my list of things to figure out because Im really curious if it can be done or not.

[Deadwood]

I agree...it's an issue that needs to be tackled...not just for me but others...I'm tempted to post this question on Autodesk forum but I'm a skerd they won't be able to help.

[Devented]

I havent had time to check out that file, personal issues arouse (as they always seem to) and im at work this morning, so I havent seen the file yet... I didnt really have a problem making the wire harness adaptable.. but only to a certain point. It was when i tried to maintian its adapatability when using inventor studio that my problems arouse, or when driving a constraint.. maually driving parts worked fine.. However, I think the solution to both our problems are probally one in the same... Hopefully, with the 3 of us trying to tackle it, and maybe someone out there seeing this, maybe a soulution can be found. On the other hand.. as you have seen.. It seems that any time this issue gets brought up, the thread usually just gets dropped, and I can't figure out why.. no one out there knows how to do this, or has ever had to do this - and found a soulution? Seems unlikely to me...

[Deadwood]

I feel your frustration fellow Canadian....I'm trying with Autodesk right now...they got a little testy when I provided a pic instead of my file design...I'm pretty new to Inventor and am pulling my hair out everyday over every little hurtle...I think I'll have to give them a working example file before they will help me fully.

 

It seems like a simple question to me....How to make a string/cable/rope?...you know, the same physical properties a string/cable/rope would have.

 

When you get a change to check out the file, you'll see how this persons hose stays with the arms as he drives a constraint...it's smooth....just a lot of parametric modeling...I think that's what it's called when dimensions are driven by others in equation relationships.

 

I think this topic deserves a step by step tutorial when finished.

[Devented]

So basically.. what the gist of these posts are pointing at, is that to make a cable/string/wire act like a cable/string/wire.. you cant use the cable/wire harness assemblies, you have to use a 3d spline? That seems kind of pointless that they wouldnt beef up the adaptablility of the wire/cable harnesses, as im assuming they were created to ease in the creation (and documentation) of wires and cables. I've known all along that using a 3d spline would probally work for what I needed it to do, however, actually drawing the damn thing to get a realistic curve of a hydraulic hose has been, well, frustrating to say the least. I wanted to use the wire harness for exactly what it was designed for.. ease of use! But I guess if you having any moving parts with wires/cables/strings/hoses attatched to it, you SOL...

[Deadwood]

3d spline is what I'm trying to learn...at least that's the direction I'm going...ya, drawing one is hard....and ya, I've tried the cable and harness feature but it doesn't move with the mechanism, never mind simulating with it.

 

From what I understand, to create 3d spline, you need to create work planes, work points, or work axis to attach the spline...the more of these points you use the more constrained/restricted it becomes...less slack...for Devented, ya gotta seriously check out the link I was talking about previously...I'm sure that's one way of doing what you want...drawing it is another, lol...I'll work on 3d spline and show what I get done...might not be till tomorrow, I'll be bald by then...hehe.

[shift1313]

when you are in a 3d sketch and you are drawing a spline you can click on the UCS icon or the planes(they will turn red).

[Deadwood]

This is what someone...I'm guessing someone with Autodesk....said on a thread I started there...

 

"It is logged as a wishlist item

Wish: NG: Customer wants a rope or wire / cable type functionality (belt joint

is not sufficient)>

 

We appreciate you bringing this to our

attention.

 

Best regards, -Hugh

 

I'm now thinking Inventor can't do this...

[Deadwood]

I'm wondering if Solidworks or Catia can do a flexible cable...I just might have access them...anybody know?