A friend of mine is thinking about building an ultralight helicopter designed by Oswaldo Durana from drawings he found on the internet. He asked if I would check the drawings for any errors and/or omissions. I know of no better way than to try to build a model first. If you cannot build a model from the drawings you probably cannot machine and assemble the parts either.
So, here are a few screenshots and videos of work in progress:
- This is the state of the assembly so far. The model is about half complete lacking the main rotor blades, the tail rotor gearbox and controls, engine mounting, engine accessories, pilot seat, etc.
The Rotax 582 engine model is by Joel Tilquin. I shamelessly borrowed it from GrabCAD since I have no details of the engine in the drawing set I am checking. ( https://grabcad.com/library/rotax-582-c-1 ) - Capture9.JPG (232.24 KiB) Viewed 3425 times
- The main rotor gearbox and engine input shaft to the high speed pinion.
. - Capture5.JPG (242.76 KiB) Viewed 3425 times
- Top view of the main rotor blade grip and pinion detail view.
. - Capture6.JPG (182.82 KiB) Viewed 3425 times
- View showing the main rotor gearbox support and blade pitch and tilt control linkage.
. - Capture8.JPG (129.12 KiB) Viewed 3425 times
This is a video of the tail rotor pitch control animated by Assembly4 to check clearances and travel limits.
This video superimposes the rotor rotation with the pitch control linked to the rotation by a sin function expression so that the pitch cycles twice per revolution.
I will add some additional posts as my spare time allows to comment on my modelling process starting with the primary structure consisting of straight pieces of welded tubing.
Code: Select all
OS: Windows 10 (10.0)
Word size of FreeCAD: 64-bit
Version: 0.20.29126 (Git)
Build type: Release
Branch: master
Hash: 6c1c63cffebe6a9d55bd9b1d8ca6b741a4d16548
Python 3.8.13, Qt 5.12.9, Coin 4.0.0, Vtk 9.1.0, OCC 7.5.3
Locale: English/United States (en_US)
Installed mods:
* Assembly4 0.12.0
* fasteners 0.3.41
* fcgear 1.0.0