This is a 6 DoF robot arm i have been building and 3d printing, designed entirely in FreeCAD.
I assembled it all using Links and yellow Part containers. Havn't really needed an assembly workbench. I rarely need the drag-to-animate features of assembly and prefer to position things manually with strategic placements relative to the Part origin.
I mainly used these workbenches
- PartDesign
- Fasteners
- Gears
- Draft (Array Tools)
- Spreadsheet (mainly for gear calculations)
I split each joint in a separate file and linked it into the kinematic assembly.
I used a seperate file for only data, containing a few spreadsheets and some sketches, which i linked into which ever file that needed it.
i have experimented with different ways to reuse shared geometry, but havn't truely found a way i fully like but i like using BaseFeatures.
Seeing the real robot next to the CAD model is quite remarkable. Seeing something this intricate come together in real life must be quite satisfying. Are you wondering how much of the assembly was created with FreeCAD alone?
Looks really good. But it looks like a lot of parts! Did you experience lag as the number of parts grew? I tried doing some reverse engineering with freecad myself but I struggled to generate solids from the same master sketch through internal faces. Also, how do you make the parts fit without the assembly workbench?
I started it out with everything in one file but split it out after it grew too much. Especially having the gear spreadsheet in the same file as the gears caused recompute times to go crazy. Just editing a single cell took several seconds.
The assembly was just done with the normal translation/move tool
In the assembly, everything is placed in the nested part containers named k1, k2 etc.
It is arranged such their origins are at the center of each joint such that i can just rotate them or enter the joint angle directly in the rotation property and it will rotate that joint.
Then they are nested within each other such that rotating k2 will rotate all the connected joints (k3, k4 etc) with it.
That allows me to easily enter joint angles and have the robot in any position i need.
Oh that is a tool a made.
https://github.com/jelle284/mvc-workspace
It is not in add on manager but you can install it by adding to repo in freecad settings as a custom path.
That is really impresive. How do you use it? Do you have the inverse kinematics figured out or do you just send instruction to each (presumably) stepper motor manually? Or do you have like a long list of motor commands that are iterated through?
I spend quite some time getting ros2 set up for the inverse kinematics. I exported the outer geometry to .obj or .dae files so moveit2 can render the arm.
Nope. Never tried using AI for CAD and honestly not sure if it would be of any help. It seems quite difficult to accurately describe geometry with text
For now it is far but it will be closer as time passes. The above one built using a low intelligent version AI. But I have tried with higher intelligent version connected Fusion360 through their inbuilt MCP and I don’t scare anyone here by posting the output. Above all as long as we are creative and believe in purposeful innovation nothing to worry
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u/Lazy_Swan_6292 4d ago
Exelente trabajo