I made a minor change to add keyboard commands to the Linkage program. It already supported the typical Control-C, Control-S, etc., keyboard shortcuts for operations like Copy and Save. It now support single key operations like C or J for Connect and Join, as well as a few others. They are all listed in the documentation.
The Windows installer file can be downloaded and run to install Linkage 2.5.8.
Download Linkage 2.5.9 Installer
After I posted this originally, I added some new simulation controls to pause and step forward and backward. Stepping is in 1/30 second increments as are all steps of the simulation in any mode.
I came across this program when looking at Wikipedia’s page on Parallel motion, which has an animated graphic drawn using it. Great, as I am looking for a non-commercial mechanical motion simulator that just does simple 2D vector animations for verifying mechanisms.
So far, I’ve only played with it a little – two things stand out so far that would be nice basic enhancements (in order of importance, as I see it):
1. Lock a length. Once you have set the length of a link, it would be nice to lock it so you can’t inadvertently change it. In that way, certain dimensions can becoming driving. Could be an option in the RMB ‘Link properties’. To me this seems a very essential requirement.
2. Since lengths can’t be keyboard-input, what if the Dimensions display could show the numeric dimension value along the dimension line, even when you zoom in? That way, you could always see the length you are dragging a line to with the mouse. At present, the value is just shown at the midpoint along the dimension line, so the value disappears when you zoom in to finely adjust the length – resulting in lots of zoom-in, zoom-out to get a length accurate. I suppose eventually, it would make even more sense to just input lengths directly via the RMB ‘Link properties’ dialogue.
3. For making a rocker link (like a see-saw) something like a midpoint snap, or else a menu-selectable anchor that has a rocker link already attached, would be good.
Thanks for the input. I started this project with zero knowledge of what anyone else might want and it’s good to get feedback.
I have thought about length locking for a long time but the editor changes to handle that while allowing dragging, rotating, etc., of things while some links have a locked length is not something I could figure out yet. It might be easy but the way to write the code to handle it didn’t immediately come to mind.
If you have a recent version of the program then you can type in lengths for things. Select a connector then select the connector that you want to move. With both selected in that order, type in the length you want into the text box in the ribbon (tool) bar length edit control. That edit control is under the box that says the type of dimensions being used, inches or millimeters. Hit enter and the second connector should move closer or further from the first connector. I have not tested that in a while so let me know if it’s broke.
You can also select a single connector and enter coordinates into that text box to move a connector to a specific point. Enter the x coordinate, a comma, then the y coordinate, and hit enter.
Links can have unlimited numbers of connectors so there is no way to make a sensible length property that works generically. Without a connector selected, it would also be hard to know which one to move when a user enters a length. These are all great suggestions and I’ll give them all a lot of thought. It would be good to have some of these improvements as long as I can keep the quick point and click interface that makes this program so easy for quickly creating a prototype.
Dave