Jump to content

Attaching propeller to a hub[Inventor]


poeli

Recommended Posts

Hi all, I'm new to the forum, quick presentation: student engineering in Brussels.

 

I'm currently working on a propeller for a UAV/Quadrocopter. I have (via a computer program and matlab) all the dimensions of the propeller blade made (now need to mirror it, or are there better ways to attach multiple blades to a hub?)

 

My main problem is that I have no idea how to attach the blade to the hub. I tried to make a cylinder as hub and 'loft' the propeller to it, but that doesn't seem to work. I've found a similar topic like this one, but the problem is that I can't even move my propeller blade or draw the cylinder of the hub. Attached is a screenshot of the blade. This is a very thin blade. Normally I would need 2 of these attached to a hub. How can I be sure that its nicely curved onto the hub. Is there an easy way of putting multiple blades on the sides of the hub? The blade consists of 31 airfoil profiles each with a certain twist on a certain distance next to each other. I have lofted them together to get the propeller.

In the hub I will make a hole to put on the engine. As this is a part of a project, I'd also make multiple bladed propellers.

 

I really hope to learn working decently with inventor (something I haven't learned in school).

hupi.png

Link to comment
Share on other sites

You have a surface body rather than a solid body.

At some point you are going to want to Sculpt or Stitch into a solid.

 

I would Revolve the hub and Circular Pattern the blades.

Then Patch the end and Sculpt.

 

Attach your ipt file here if you can't figure it out.

Link to comment
Share on other sites

Thanks for the quick reply. I was already wondering why the loft was brownish and not the 'normal' color. So if I understand correctly, it is so brownish because it needs to be attached to another solid? I have done nothing 'special' with the loft feature i guess.

Back to the hub: if I revolve it I have the problem that when the hole is small the entire revolving is also small. The hole should be a specific size to fit on the engines, but the sides should have some strength. This is wat I got, still trying to figure out most of the terms you mentioned, I'll read some tutorials for them first. I've attached the ipt too, but in the end I'd love to be able to do it myself of course :-) I must sound as a complete newbie, but I do want to be able to do it myself. It will take time which I don't have.

9783.png

 

I'll try now to get the hole at the right size first before going further with the other things you mentioned. A big thank you sir!

File: Propblade.ipt

Link to comment
Share on other sites

The sketch for you hub isn't constrained?

Have you read this http://home.pct.edu/~jmather/skillsusa%20university.pdf

 

I had something like this (add the hole after the revolve).

Then add a nose cone.

 

PROP.jpg

 

You have a serious problem in your blade sketches.

Edit Sketch2 and zoom way way in on the pointy end.

What do you see?

Link to comment
Share on other sites

Thanks. So you can't rely on inventor to draw a spline through the points when i import them from excel? Could this also be the reason that the loft was done as surface and not as solid?

I will read the document you gave me first. Will have some work with it but I hope that once I finish the first prop the rest will go easier.

Link to comment
Share on other sites

Thanks. So you can't rely on inventor to draw a spline through the points when i import them from excel? .

 

Sure you can - but you have to make sure it is closed.

 

I would have done very differently - probably only 2 profile sketches and two guide curves. (I try to avoid work.)

Link to comment
Share on other sites

Ok, will consider that in the future. The problem is though, all the profiles are calculated to have minimum induced losses. I have done 'only' 30 profiles, i have seen people use 50.

Now I have a solid instead of a surface. First step in the right direction I guess. I'll have a look at the other document now and then get up early tomorrow. That's one sweet looking prop you've got there. I hope to have something similar at the end of the week! Thanks for the support, greatly appreciated.

Link to comment
Share on other sites

I really should get into the program more and follow some training. Last year engineering student and no decent training in Inventor is a real handicap in my opinion. Now I have the solid blade, and a hub (Why actually revolve the hub instead of just extruding actually?) This is what i have now, just the blade with a extruded hub. Now I'll look to attach both and have a second look at the circular pattern, as this would be much more easy than just mirroring. I'm going to the library in a minute to see for some books on Inventor. Edit: just was able to use the circular pattern feature. Now trying to attach it to each other to get one solid part.

b9i.png

Edited by poeli
Link to comment
Share on other sites

I made some progress but am not happy with the result so far. I was able to make the hub and to do a circular pattern, but I really can't find to make it a 1 piece (1 solid) prop (which is needed to make a mold it seems?). I found people stating using 'Derive component'. Using the function combine doesn't seem to work (I'm most probably doing something wrong there).

My end objective is use the ipt file for a 3D printer and making a mold using a CNC machine.

iean.png

 

smallehub.ipt

Link to comment
Share on other sites

Find the red End of Part marker in the browser.

(End of Folded on sheet metal parts EOF)

Drag the red EOP to the top of the browser hiding all features.

 

Save the file with the EOP in a rolled up state.

 

Right click on the file name and select Send to Compressed (zipped) Folder.

 

Attach the resulting *.zip file here.

Link to comment
Share on other sites

  • 2 weeks later...

Sorry for the late reply. This worked, thanks for the support. This afternoon I'll do a tutorial on mold design for the part. With that i have the following problem. I'm trying this tutorial: http://de0qmbqba3hfm.cloudfront.net/attachments/62311/0 but I don't see the mold design tabs appear, only the standard ones. I have checked the 'Inventor mold metric' library, without any change. How could I solve this?

This is what it looks like:

ykon.jpg

Edit: I read it is because i use windows 8? I will go to school tomorrow to check if it works there.

Edited by poeli
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...