Simulation aborted

deskpilot

Though you might like to see the plane this is for. Not my design but I'm enlarging it to take my 100kilo frame and will putting a more powerful engine to it. The original is called Sgian Dubh which is Gaelic for dark or hidden knife. (usually tucked into a Scotsman's high sock.)

photo shop.jpg

Anton_S

That's a nice mechanism I never seen something complex before. I love it!

Your design of the rear wheel gear mechanism did not turn out vertical when the gear was lowered, but I made the two vertical bars 40mm shorter, and as of result the mechanism worked very well. I think rear wheels could go lower, to contact the floor, but I'm not sure on how you want it setup. I posted the model for your investigation. It will be very easy to tweak landing height. You don't have to redraw all arms and change their height. All you have to do, for testing purposes, is move hinges (axis of rotation of arms) a few mm up or down, test it, and then once you find the right alignment, you can redraw arms to their desired lengths.

Main wheels mechanism trial.skp

deskpilot

Anton, Anton, Anton. Thank you so much. You did a great job, but we're not there yet. I have to have the full ground clearance so the the 'pusher' propeller doesn't touch the ground as the aircraft rotates for take-off or on flare as it lands. I'll look at getting the nose wheel to fully retract and for the mains to come down lower. I practice, there will be lots of changes to make the whole thing strong enough and stable in the 'X' axis as well. This, though, give me the optimism to carry on.
May all your dreams come to fruition in the new year. Doug

Anton_S

Thanks, man! I'll be there to help out. At some point I might create a video explaining how I added joints, grouping and connection order, and other rules that at some point will be handy when using SP.

Happy a happy new year!

deskpilot

Greeting Anton. Firstly let me wish you and yours a very safe, healthy and prosperous new year.
I'm so glad the 'silly season is over. Perhaps life can get back to normal now.

I've modified my nose gear assembly to include the control lever but something is keeping the leg locked as if it were set to static. The small 'locking' link is the same. If there's something hidden, I can't find it. Care to take a look?
The final operation should be, starting with the lever fully back as modeled, pushing it forward should rotate the nose wheel leg to be horizontal and tucked up into the blue foam. Hopefully, the curved actuating bar will reach over the locking mechanism without crashing into it.
Looking at the main wheels, it appears that this might be a step too far in that weight is the enemy and when I add the second system (right hand side) I see a whole lot of weight, and I haven't got the interconnecting hardware modeled yet. Might have to accept a fully streamlined fixed main gear for starters.

WOW, didn't realize file was so big.

Anton_S

Here you go!

The small group with two hinges connecting wheel to the lever part - was too small. The 'Default' shape in SketchyPhysics can't process small objects, and it doesn't work so well. Use 'Convexhull2' shape instead. It handles small objects properly.

Here is your fixed model. I managed to get it under 3 MB by purging unused definitions. Here is how you do it in case you interested:

Open Ruby Console, and paste this command:
Sketchup.active_model.definitions.purge_unused

Also, using TT CleanUp plugin is recommended too. It removes all unused edges and other geometry.

It is a good practice to purge unused geometry from your model before uploading it somewhere.

revised nosewheel assy.skp

deskpilot

Thanks Anton. I do have TTcleanUp installed and use it. As to why there are still so many errors......?
I'm using the free version of SU and SP, maybe there's a limit to what can happen. Currently I'm trying to get SP camera to work so that I can send an .avi file to the plane's designer. Seems there no tutorial for this and I'm doing the necessary research on the web for inspiration. Do you know where the files are saved?

deskpilot

Cheers mate. nothing's as easy as SketchUp/SketchyPhysics is it....................NOT

Anton_S

Yes, SP could have been made easier to use. I'm working on MSPhysics (a similar project to SP) and I will attempt to make as easy to use as possible.

deskpilot

Anton, I've installed Makeavi and have loaded 2500 images. Unfortunately, something goes amiss and the resulting 'video' is split into 4 displaced sections and colours are totally changed. Any idea's as to what I'm doing wrong. I don't get the compression choice you mention but there is a cropping option that I haven't used.

deskpilot

Sorted, sort off.

Anton_S

When insterting images, try inserting them all at once:

Click Add Files button.
Select Ctrl-A and click open. This will import all images at once, in sorted form.
Set Playback frame rate to 60.
Click the Begin! button.
Select video location and name.
Afterwards Video Compression options dialog will pop up. Select Microsoft Video 1, set Compression Quality to 75 and click OK.
Afterwards use desired video converter to convert AVI to mp4 or any desired format. You'll find many free video converter software online by google searching free video converter.

I updated prior post with using MakeAVI instructions.

Anton_S

The free version of SU should work the same as the licensed version.

To export an animation, do the following:

Enable SketchyReplay Record button
Press play and run simulation for desired time
Reset simulation. It will ask you whether to save animation. Click YES.
Go to (Menu) > Plugins > SketchyReplay > Export Animation.
A dialog with options will be displayed.

Set ReplayCamera? to YES if you want to replay your camera movements.
Set Save As to PNG or JPG.

Press OK. This will lead you to choose a saving location. Once you done, a set of images will be exported into the chosen folder.
Use desired software to combine images into a video. I suggest using MakeAVI. See next steps for instructions.
One last step. Select (Menu) > Plugins > SketchyReplay > Erase Record. This will remove all animation export data from SU file, which will reduce file size.

Using MakeAVI:

Launch makeavi.exe
Click Add Files button.
Navigate to folder where all generated images are stored.
Select Ctrl-A and click open. This will import all images at once, in sorted form.
Set Playback frame rate to 60.
Click the Begin! button.
Select video location and name.
Afterwards Video Compression options dialog will pop up. Select Microsoft Video 1, set Compression Quality to 75 and click OK.
Afterwards use desired video converter to convert AVI to MP4 or any desired format. You'll find many free video converter software online by google searching free video converter.

mptak

I noticed that Processing (2) has added some moviemaking from images capabilities. As Processing has risen to the top of mylist (along with the new improved SK physics) I will be curious to hear if others are using Processing with SK physics.

deskpilot

G'day, g'day, g'day. Anton, I know you've just been hanging for my next problem. Besides which, you're getting excited about my project,aren't you

I've had to look for what might be a much lighter retract system and this MIGHT be it.

Pivoting about the center of the mounting cylinder, the oleo (landing leg)rotates back and up till horizontal(90*) and then the leg swings in until the cover is flush with the fuselage skin(??*), see starboard side). These operations could have some over-lap provided nothing crashes into the skin. That's the bit I can't do (off one slider with built in delay for the swing in?)
This is fine in theory but not sure how to do it in practice as yet. When you have time my friend, and an explanation of how to control two or more servo's from one slider please.
Cheers, mate.

Rearward rotating mains.7z

Anton_S

Pretty cool gear designs!
You can use one slider to lift gear. I added script to make it delay the way you want. If you're interested, the script is located in the red box.

To see the physics joints, turn on the layers panel and enable the Physics Joints layer.

Note: There is one thing you should have done to your model before posting - run cleanup. Doing that, I was able to reduce model size to just 651KB (even without zipping). I would suggest using TT CleanUp plugin. When you ready to upload the model follow these insturections:

Go to (menu) Plugins > CleanUp > Clean...
Make sure scope is set to model.
Make sure optimizations purge unused checkbox is enabled.
Press CleanUp button, save model, and your good to upload.

Rearward rotating mains.skp

deskpilot

Thanks Anton. I think I've said before, I purge and clean before posting so maybe I have a problem somewhere. Got TTCleanup installed.
Great to see my idea working, just got to figure how to make it happen using levers etc. instead of black magic )

Anton_S

No problem mate. Ask for help anytime you want.

Maybe you used TT Cleanup to clean particular selection rather than the whole model. Next time ensure that the Model radio checkbox is checked.

Levers are good chose too. Black magic is just more efficient

deskpilot

Hi Anton, I'm back, this time with the same problem that started this thread. I've done something ???? and now I'm getting the same massage as per first post. Would you please tell me how to fix it this time as my model isn't ready for posting to you.

Cheers in advance, Doug

Anton_S

Are you using SketchyPhysics version 3.5.5? Go to (Menu) SketchyPhysics -> About to check version.

If not using SP 3.5.5, then upgrade!
If you're using SP 3.5.5, the error could be coming from a 'Scripted' property of some object.

Open SketchyPhysics UI panel and select any group other than a physics joint. You will notice the UI webdialog displaying various body properties, such as 'Magnet', 'Thruster', 'Emitter', 'OnTouch', 'Ontick', and 'Scripted'. The Scripted field allows user to assign a piece of Ruby programming code to an object. The programming code is then evaluated when simulation starts. It appears that one or more objects in your model have a programming code; however, with a syntax error. Whenever there is a syntax error in a programming code of the 'Scripted' field, simulation resets and displays the error message.

Anyway, to fix the error, you must first find an object that contains some code in a 'Scripted' field and then check for any incorrect syntax. Maybe you accidentally added/removed a character, which caused a syntax error... I assume that this error is generated in over-center_lock_mechanism.skp model that I sent you earlier. If so, there are a few objects that contain this code in them:


onStart {
  setMass(1)
}

If you find an object that doesn't contain this code, then replace it's code with this code.

If you can't find it, then upload the model and I'll do it for you. You can upload it via private message if you want to.