Cable/Chain Design in SW
Cable/Chain Design in SW
(OP)
I'm having trouble trying to design systems that utilize chains or cables that have to route around gears, rollers, sprockets or cams. I would like to know how you are accomplishing this task, in the hopes that it will turn on a few lights for me.
I am most interested in what techniques you are using in SW to simulate these types of movememnts during the design phase. Most of my design work revolves around fixed pivots, linear actuators and simple hinges. Now I have to design something similar to a chain or cable being fixed at one end, with the other attached to an eccentric cam to provide more/less movement at certain times.
I usually build a layout sketch first (skeleton?), which represents all major moving components. I drive this layout with dimensions to ensure my geometry works well, then I instert that into an assembly and start creating simplified parts in-context to the layout. Once these parts cover all major compnents, I loose the in-context relations and start to detail the subsystems into their respective components.
Thanks to all.
I am most interested in what techniques you are using in SW to simulate these types of movememnts during the design phase. Most of my design work revolves around fixed pivots, linear actuators and simple hinges. Now I have to design something similar to a chain or cable being fixed at one end, with the other attached to an eccentric cam to provide more/less movement at certain times.
I usually build a layout sketch first (skeleton?), which represents all major moving components. I drive this layout with dimensions to ensure my geometry works well, then I instert that into an assembly and start creating simplified parts in-context to the layout. Once these parts cover all major compnents, I loose the in-context relations and start to detail the subsystems into their respective components.
Thanks to all.
"The attempt and not the deed confounds us."






RE: Cable/Chain Design in SW
I have read your problem.For this type of cable I use Layout scetch.I mean creating a part in the context of an assembly.I have one sample for you if you want.
Contact me for it by Mechanicam@hotmail.com
best regard
RE: Cable/Chain Design in SW
I am looking for a method that will allow me to push/pull a cable/chain around sprockets/gears in my design that will allow me to see this motion accurately.
"The attempt and not the deed confounds us."
RE: Cable/Chain Design in SW
If you only need to simulate the motion occasionally, you might be able to save yourself some money by using the API to drive the animation. You can't use Animator for this because with cable/chain you aren't dealing just with moving components. You also have the cable component which is changing shape as the mechanism moves. You need to adjust the driving dimensions/mates and rebuild the assembly repeatedly to simulate this. I have used equations to update the cable path sketch dimesions such that the total cable length stays constant as the various lengths in the path sketch change. Here is a simple example of how you might drive a mechanism and update the cable path sketch dimensions (H and V). This would be a custom job each time, but for simple mechanisms wouldn't be very difficult.
******************************************************
Option Explicit
Dim swApp As Object
Dim Part As Object
Dim start As Single
Const TotalLength = 1
Sub main()
Set swApp = CreateObject("SldWorks.Application")
Set Part = swApp.ActiveDoc
Do While Part.Parameter("V@Sketch1@Cable.Part").SystemValue > 0.1
Part.Parameter("H@Sketch1@Cable.Part").SystemValue = _
Part.Parameter ("H@Sketch1@Cable.Part").SystemValue + 0.01
Part.Parameter("V@Sketch1@Cable.Part").SystemValue = _
TotalLength - Part.Parameter("H@Sketch1@Cable.Part").SystemValue
Part.EditRebuild
Part.GraphicsRedraw
start = Timer
Do While Timer < start + 0.01
DoEvents
Loop
Loop
End Sub
RE: Cable/Chain Design in SW
go down to very small increments. While this is probably acceptable for your own use, if you want others to see the motion then it might be a good idea to write out an image of the assembly at each step and use a video editor to pull them all into an AVI file.
RE: Cable/Chain Design in SW
RE: Cable/Chain Design in SW
Happy New Year to all.
"The attempt and not the deed confounds us."