ACTS (8) – Part 1 – Moving a submesh per animation smooth over time to a precise position


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I don’t know if it is of some interest for some one, for it is a milestone.

Three months I experimented and tested and readed a lot of stuff. Now I have reached a big step for me and the aCTS: Moving a sub mesh accurate to a mm relative to the origin (may be an attachment point too?) of the “parent” mesh. And the idea may be used to break the mm more down, that I haven't tested yet.

The first destination goal was to move a bridge crane to the designated position. This isn’t possible to do by train, or I don’t know any way. And at the moment there is only one direction (Y) to move.

The solution idea I got while thinking about the dimensions of a more parted telescope bar. So I created a crane base (the area where the containers take place). The crane itself is a submesh of this.

Here is the first abstract model for it:

The crane(gear) walks from container to container and stays for 10 seconds. The speed is with 30 fps on meter for 5 frames, ca. 6 m/s. The container will be positioned randomly within the cranes area (here one for 100m and one for 140m. And of course it's possible that the containers overlap each other in these test assets, but they will be positioned one after on.

And the functionality doesn’t append from the length of the crane base mesh, but from the length of the animation of the dummy-mesh. The dummy mesh should be of course invisible but isn’t yet.
The script does all the rest, if one sets the right animation parameters, fitting to the used meshes.

If one likes to have a look behind the scenes, feel free to pm me.

I made a small video for this: “aCTS ANIMATION first milestone.mkv”

And the main goal is here not a beautiful model but only the functionallity.
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It certainly is of interest yes! I love what you are doing, it looks like a great project and would certainly add some more realism to Trainz if a container terminal would actually load individual containers!!! Keep up the good work ;) Is your plan to incorporate this into an industry asset that will then individually load/unload containers from one wagon at a time??
If it is possible to posit the cranegear at each position in the accuracy of 1 mm, yes of course. I don't know yet if it should be an industry, but it looks like. First the aCTS-asset shell be something like a base asset like the industry-base or so. And the model shell be buildable around it. That's because my skills in modelling are more less then bad and my patience for small details isn't as great as it should be.
So my next steps are moving right/left (X), up/down (Y) and rotating the gear.
And let me say again: My main goal here is not a beautiful model but more the functionallity.
Well you legend! When you get a nice functionality, let me know and I will happily work on a model! If you can get the script to float carriage locations then I suppose you can make the crane navigate to them...!
Congratulations on reaching this milestone! Your innovative approach to moving a sub-mesh accurately within the parent mesh is impressive. The crane simulation and the video you shared demonstrate a great achievement in functionality. Keep up the good work!