323Z CAD Section

VEX V5 General Discussion General Forum
1

On our website we have the CAD section. What other stuff would you like to see up there? We just re-did the 4-Bar and 6-Bar here: http://www.team323z.com/lifts.html

Right now my plans are to build the following (for both lift and drive):
Chain Bar
Scissor Lift
H-Holonomic (Re-do)
X-Holonomic
Tank Drive
Planetary Tank Drive (maybe ;))
Drive to Lift PTO?

What else do you want to see? I can maybe do an elevator lift (never built one in my life, but can do it), Reverse 4-Bar, and 8-Bar? Let me know.

We will be adding more information on the lifts. I just threw it up there real quick. The one thing I like about it so far is that is has the math equations to figure out exactly how much it will lift. I will get some other equations up soon.

2

Hey jesse, I would be interested in the elevator lift, because I to have never built one either and would love to see how it works (in depth). I myself love to cad and would be happy to help you along the way.

  • love the cad models so far.
3

you have the math right for how much i can lift, but you use the stall torque which means that at that much weight it wont be able to lift it. In this thread jpearman sugests that you should not run you motors under 60 rpm at full pwm value so as to not trip the ptc.

https://vexforum.com/t/motor-torque-speed-curves-rev2/21868/1&highlight=motor+data

you can use the chart to see what the torque is at that speed. This way you know how much it will actually lift.

Another thing is the gears are not 100% efficient, so i would multiply the and weight by .8 and use that. This would be assuming that the gears are 80% efficient. The gears are probably somewhere close to this value.

You could also add how to figure out the time it would take to get to a certain height assuming that there was a specific amount of weight at the end of the arm.

Also i find it somewhat difficult to read with the green and the white.

I also would add a larger division between the sections with a horizontal bar or something.

Over all very good

4

Hey dude I like the way the page is coming along. Do you mind if we copy your information verbatim into our lifts pages?

5

Thanks :slight_smile: Why not :wink: Go ahead!

(Just give the credit for the images and text if you use it to 323Z)

6

Edited the Drive section of our page: http://team323z.weebly.com/drive-train.html

Please let me know if I have anything wrong and if you like the page! Hopefully our website can be a tool for other teams to use!

I’m thinking of adding a misc CAD section where I can add transmissions, planetary gearbox, other random things. Would you like it?

7

this is nit picky but the symbol you have for force parallel is the force perpendicular symbol( i believe). Usually it is like two small parallel lines after the f at least in my experience.

8

How are you getting the images of your CAD? It looks like inventor studio, but I see the tool bars, which would not apear in it. It looks too good of quality to be just a screen shot.
For your lift CAD you could make 5-10 second movies of them going up/down and post them as well

9

I’m using Autodesk Inventor and I screen shot all the images. It is very good quality :wink:

If you could teach me how to make an animation with my lift, I would do it :smiley:

10

Animation in Inventor studio:

Simple lift I created:
[ATTACH]7589[/ATTACH]
Each side contains a 3 bushing at the top of the C channel
The left C channel is grounded
The 2 3 bushings are connected by a insert constraint with a distance of 1 inch

You should now be able to spin the second C channel as a lift would

Place an angle constraint between the 2 C channels to your starting angle (in my case 0 degrees)

Open inventor studio: (Environments/Inventor studio)

In the parts list box on the left side (I do not know what its official name is) expand one of the parts that has your angle constraint (the 3 bushing) right click on the constraint and select animate constraints

Select the ending angle and the time

This is how it should look now:
[ATTACH]7590[/ATTACH]

Press OK

You can drag the time bar to see how the animation acts as time progresses

To publish click render animation
Configure all of the attributes to your liking

(Make sure you only render the length of your animation do not render 30 seconds for a 5-second animation)

I recommend doing a series of images instead of a movie because it will be better quality, and if something goes wrong, you can start from where it left off instead of starting over
I then import all of the pictures (sometimes 1500+) into an Adobe premiere elements project and use the time stretch tool to make them all 1 or 2 frames long
When doing pictures you are more concerned about the total number of frames than the FPS and length because you are correcting this when you make the movie (30 sec 30FPS=60 sec 15FPS)

Select render

The movie/pictures will render (this may take a very long time, 24 hours+ for complex assemblies)

Inventor studio can do a lot more than this, there are many different settings including cameras, lights (fun to play with)
You can have multiple constraints being animated at once, cameras moving, and lights moving as in this solar tracker I did a week ago.
The render took 15 hours and produced 900 frames totaling 2.5 GB
I combined these frames into a 30-second 30FPS movie and a 60-second 15 FPS movie

http://www.youtube.com/watch?v=5NbYAAbs4Y4&feature=youtu.be

Demo video of lift from this tutorial:

[Inventor Studio Output video from tutorial on Vex Forums - YouTube

Render time: 12 min
Frames: 150
Time/frame: 4.8 seconds
FPS: 15
Length: 10 sec](Inventor Studio Output video from tutorial on Vex Forums - YouTube)
normal.jpg
studio.jpg