sync rotation

Hello,

I am trying to design the engine movement, but I can't find the relation between the connecting rod and the piston.

I think that the piston movement (y) should be controlled with an "sin x" function of the same angle that is controlling the drive shaft rotation, but how can I maintain the same length of the connecting rod?

Maybe the image helps.

thanks.

Attachments:

Screenshot_2010-06-08_17-23-31.jpg, 209 KB

Replies to This Discussion

Permalink Reply by Daniel Piker on June 9, 2010 at 8:22am

The movement is not just a simple sine function.
Rather than trying to define the movement with an equation use a circle and intersect it with the line.

Attachments:

piston.ghx, 235 KB

Permalink Reply by paul piciorul on June 9, 2010 at 10:20am

yes!
I was working in the same direction to find out the relation between the sin movement and the constant distance.
thank you!

Permalink Reply by paul piciorul on June 10, 2010 at 4:56am

what kind of component did you use to create the curve? and the rotation?
I obtained the same result but rotating the evaluated point with rotate with axis.
anyway, thank you for your help.
paul.

Permalink Reply by Daniel Piker on June 10, 2010 at 5:10am

I posted the full .ghx definition with my reply above ^

Permalink Reply by WT4 on June 10, 2010 at 1:35am

How did you get create this video? Did you use something like CAMTASIA.
Also how did you actually get grasshopper to play the animation.

Regards

Permalink Reply by Daniel Piker on June 10, 2010 at 4:25am

It's the usual slider animation exporting a sequence of .PNG stills from grasshopper. Then made into an animated GIF in Gimp.

Permalink Reply by WT4 on June 10, 2010 at 6:03am

OK it is just that when I saved the stills as jpg or bmp, paintshop pro does not seem to recognise the format. With png files it is OK. I don't suppose you have a version that can be loaded into 6.00059.

Many thanks

Permalink Reply by Daniel Piker on June 10, 2010 at 6:45am

Yeah, I also have problems opening bmp files generated by grasshopper for some reason. Anyway png is a good format - smaller files than bmp, but still lossless unlike jpg.
I made the def in 0.7, and there is no way to save in an earlier format, but here is an image of it