Jump to content

Scissor Lift Rig anyone?


CarlAhearne
 Share

Recommended Posts

Hi guys and girls,

 

Having spent a little while looking for any help kn this, I'm stuck... Basically I want to be able to rig a scissor lift in 3DS Max, and I'm not sure where to start.. I'm thinking that there are going to have to be a combination of Look At Constraints, Orientation constraints, moving of pivot points etc.

 

I've started to have a go, but I just can't seem to get it to work so I've just about given up...

 

Has anyone had to do this before? Should I be thinking about bones? (I've never used them before though..)

 

Any help on this would be great, and if I can get it to work, I'll be happy to share the model at the end..

 

Cheers,

 

Carl

Link to comment
Share on other sites

Spline IK and wire controlls

 

 

What you do, Create a spline with two vertices, make it renderable as a box. Put its pivot at the far end, duplicate and mirror for the other end. Rotate them both about 5% up and then duplicete them again in the z axis for as many scissors you want.

 

Now comes the fun part, You have to wire the rotation of all the splines to one controler object such as a another box that rotates. this way, when you rotate the controler box all of the scissors are rotated.

 

Then for every spline object apply a spline IK control modifier separately, and then hit the button 'Create Helper' This creates dummies at the vertex ends of a spline. Now you can attach The scissor parts that needs to move up automatically to the dummy that it must stay connected to, and repeat for all the scissors.

 

I hope you understand otherwise I'll demonstrate more clearly later. End of the day for me so I'm outa here

 

G'luck

Link to comment
Share on other sites

This is so great cause I just did a search today cause I have to do an out door lift for a grocery store. I look forward to see how it is you created this. I tried to follow you and I must have missed something some where?

 

Wondering if it has something to do with mine being a bit different. Mine is just one set of crosses but they slide at one side also.

Edited by Sourpickles
Link to comment
Share on other sites

welcome to the forum.

 

You'll have to post a bit more so that you get the rights to post links and photos. If you have a name of the lift then i can maybe have a look on google.

 

Ill do a more clearer tutorial with some screen shots. just give me some time

 

cool

Link to comment
Share on other sites

Sweet!

 

I been coming here to the site for maybe...ooohh...... 6 years?

 

I was able to get something to work. I made a point helper. Moved it off to one side. Wire parameter set up being point helpers z and the rotation of y of the dummy object divided by 82.

 

z_rotation/82

z_rotation/-82

 

So put those on the respective dummies and it seems to be working correctly...... seems to. So I'm happy! Took me some thing like 2 hrs to figure it out and only 40 to build the scene.....aaah to be on salary! :)

 

Thanks for the offer to help. I'm still going to check back in later to see how you did it and maybe use that as well.

Link to comment
Share on other sites

Koper,

 

Thanks for having a look at this; what you have done is pretty good; I was getting close to that but the problem I have is that I have a scissor lift similar to the one Jason describes, whereby only 1 of the nodes at the base is fixed, and the other one slides in and out. The scissors are then fixed at the centre of the arms... I'll draw a picture if I get a chance...

 

Thanks again for having a go though; your technique is far better/cleaner than the aproach I was taking... Hopefully we can come up with a solution to create the type of movement both Jason and I seem to need...

 

Carl

Link to comment
Share on other sites

O...k

 

Well, I guess its a bit more complicated.

 

As a start, then wire the main rotation point helper to it self and let the moving axis (X or Y) control the rotation axis. But you'll have to divide the x_position controll by a certain amount to make the rotation less.

 

Don't know how you'll keep the centers fixed though

Link to comment
Share on other sites

I really should get IT to install 2010 so that I can actually look at the file!!!

 

 

Aw man I'm sorry. This is my first project using 2010 too! If you can think of a way I can save so you can view it I'll see what I can do. Tried a 3ds file but it doesnt preserve any of the links and what not. And obviously you cant open it with 2009 cause you know....why would they want you to do that? :)

Link to comment
Share on other sites

all I did was like I posted before and the other guy just mentioned.

 

1. Make a point helper off to the side

2. 2 dummy boxes on the two ends that will be stationary

3. Wire param the point helper to one of the dummy boxes.

(mine went point helper z position to dummy x rotation I believe)

4. Connect the point helper to the dummy in the dialog box

5. Made the rotation command "/82" (which means divided by 82)

6. Did the same thing to the other dummy but that one I made negative. "/-82"

 

So that way it's rotating at basically 82% less? I can move my point helper up and down the 4' I need it to move and the two arms rotate at a small amount and made the lift lower which then made the arms look like they were sliding on the other side. Seems that "the center point" stays at the same place, which is something I was worried about too, but seems to be fine. They are both rotating at the same speed.

 

Now I will admit I kinda cheated a bit. When I set my rotation at the dummies I did go in and rotate my arms a bit to make sure they moved along and kept in the correct locations. That's were I think I may be at a 90% correct set up..... but hey IT WORKS! it's what I needed and does what it needs to do.

 

Does that help you out at all? Figure give you something so you don't have to wait to get home :)

 

 

 

 

Wanted to add..... since you have more arms you'll do what the other poster mentioned which is set the number higher on the other dummies as you go up the scissor. Cause of the rotation speeds.

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share

×
×
  • Create New...