Zeldaboy14
Owner of ZPW.
I've already animated stuff in blender. I know SIMPLE animations, but I don't understand the more complex animating of the coupling rods.
Help Needed: Animating Siderods
- Thread starter Zeldaboy14
- Start date
Zeldaboy14, I'd like to help, really, but I need some information before I can. First, what simple animations have you done in Blender? Second, how many of the 578 videos on Youtube that relate to the Walschearts valve gear have you looked at already? I don't want to refer you to a tutorial you may already have viewed. Have you consulted the Wikipedia article on the Walschearts gear? The section "technical details" gives a good explanation of the various parts of the gear, and should be helpful in communicating with experienced steamers about the details of what you want to do.
Meanwhile, in one one of the other trainsim universes, a bloke by the name of Mike Adams did a Walschearts tutorial using Blender 2.49, which is downloadable. You'll have to log into the site to download, and to be honest, I didn't try to do it, so I don't know what all that entails.
Good luck.
ns
Meanwhile, in one one of the other trainsim universes, a bloke by the name of Mike Adams did a Walschearts tutorial using Blender 2.49, which is downloadable. You'll have to log into the site to download, and to be honest, I didn't try to do it, so I don't know what all that entails.
Good luck.
ns
narrowgauge
92 year oldTrainz veteran
Zeldaboy.
Animating the coupling rods is the simplest part of the whole exercise. You say you have done animations in Blender, did you export them into Trainz and did the animation behave as you expected.
Trainz requires a dummy b.r.crank at the centre point of the crank pin, linked to the wheel dummy b.r.wheel (which is animated to rotate) which in turn is linked to b.r.main which is the central point of the whole bogie. Align your coupling rod and link it to the b.r.crank. Now you have to prevent the b.r.crank dummy from from rotating around its own axis, this is easy in Gmax but I have no idea how you do it in Blender, this causes it to keep the coupling rod from swinging around in the air. At this stage, export it and test it. If you have done it right your coupling rod will appear to be connected to all the wheels on that side.
If ir works then repeat for the other side.
One thing that is important in Gmax and Max is that all dummies must be created in TOP view with the bogie pointing front-down. I assume that the same rules apply in Blender. The dummy names are not critical but it is good practise to name then according to their purpose as I have done above.
Get to this stage, then we can cover the Connecting rod animation.
Peter
Animating the coupling rods is the simplest part of the whole exercise. You say you have done animations in Blender, did you export them into Trainz and did the animation behave as you expected.
Trainz requires a dummy b.r.crank at the centre point of the crank pin, linked to the wheel dummy b.r.wheel (which is animated to rotate) which in turn is linked to b.r.main which is the central point of the whole bogie. Align your coupling rod and link it to the b.r.crank. Now you have to prevent the b.r.crank dummy from from rotating around its own axis, this is easy in Gmax but I have no idea how you do it in Blender, this causes it to keep the coupling rod from swinging around in the air. At this stage, export it and test it. If you have done it right your coupling rod will appear to be connected to all the wheels on that side.
If ir works then repeat for the other side.
One thing that is important in Gmax and Max is that all dummies must be created in TOP view with the bogie pointing front-down. I assume that the same rules apply in Blender. The dummy names are not critical but it is good practise to name then according to their purpose as I have done above.
Get to this stage, then we can cover the Connecting rod animation.
Peter
trainman7616
Western Maryland Addict
This is a animation for the type of valve gear your looking for.
Zeldaboy,
This is a very ambitious bit of animation and good luck. May I suggest you download Torsten's Blender exporter test set at https://bitbucket.org/uschi0815/blender-exporter-for-trainz/downloads/
One of the tests is called "steam anim 2" and can be the basis of your animation. i.e. the piston housing, piston and the main rod (aka connecting rod). This all drives the flywheel which would be the main driving wheel. As said earlier it helps to know the correct naming of the "parts" and there would be information on the web for that.
I like to think of the components mentioned above as the "heart" or "engine" of a loco drivers animation as all of the other parts "follow" or are influenced by those parts.
Making a Walschaerts animation of this type is relatively easy since the piston always moves in a horizontal direction. Making one for a sloped or angled piston is a real PITA.
Start with the model mentioned above and adapt it to match your base drawing in Blender. Do not add any extra parts until you have it aligned with your drawing and with the animation still working. This is really important.
Gradually add each new part and animate that part. You will need to decide what "drives" that particular part and what constraint or other influence is required. This is the hard bit and you should look at Paul Hobbs tutorial for ideas.
When animating my Big Bertha "drivers" I wrote a couple of blog articles on it. See http://forums.auran.com/trainz/entry.php?173-Big-Bertha-Build-Animating-the-bogey-1 and http://forums.auran.com/trainz/entry.php?187-Big-Bertha-Build-Animating-the-bogey-2
If you get really stuck then I'm prepared to give you the source for my Big Bertha drivers animation. However, I will point out that starting with that source and adapting it to your requirements is unlikely to work. It is for a sloped piston and it is not a standard Walschaerts arrangement. But you can at least see what I did.
This is a very ambitious bit of animation and good luck. May I suggest you download Torsten's Blender exporter test set at https://bitbucket.org/uschi0815/blender-exporter-for-trainz/downloads/
One of the tests is called "steam anim 2" and can be the basis of your animation. i.e. the piston housing, piston and the main rod (aka connecting rod). This all drives the flywheel which would be the main driving wheel. As said earlier it helps to know the correct naming of the "parts" and there would be information on the web for that.
I like to think of the components mentioned above as the "heart" or "engine" of a loco drivers animation as all of the other parts "follow" or are influenced by those parts.
Making a Walschaerts animation of this type is relatively easy since the piston always moves in a horizontal direction. Making one for a sloped or angled piston is a real PITA.
Start with the model mentioned above and adapt it to match your base drawing in Blender. Do not add any extra parts until you have it aligned with your drawing and with the animation still working. This is really important.
Gradually add each new part and animate that part. You will need to decide what "drives" that particular part and what constraint or other influence is required. This is the hard bit and you should look at Paul Hobbs tutorial for ideas.
When animating my Big Bertha "drivers" I wrote a couple of blog articles on it. See http://forums.auran.com/trainz/entry.php?173-Big-Bertha-Build-Animating-the-bogey-1 and http://forums.auran.com/trainz/entry.php?187-Big-Bertha-Build-Animating-the-bogey-2
If you get really stuck then I'm prepared to give you the source for my Big Bertha drivers animation. However, I will point out that starting with that source and adapting it to your requirements is unlikely to work. It is for a sloped piston and it is not a standard Walschaerts arrangement. But you can at least see what I did.
I just want to clarify something I said in my first post about the "engine" of an animation. The picture below shows much of the animation for my Big Bertha drivers but with some meshes hidden for clarity.
The highlighted (yellow) lattice is the only part of the animation that has key frames. All of the other lattices and bones "follow" that lattice's animation through the use of constraints and "parenting". So the "engine" is actually the axle which is totally reversed from real life.
BTW the bones going more or less directly downwards, link to a point 100 metres below the model. This is a trick described in Paul Hobbs tutorial and, I believe, was an original idea by Bill Fock. It makes an attached mesh move through a very small arc on a very large circle and helps piston movement on sloped cylinders. This would not be needed for Zeldaboy's model.
It's fun just watching all the bits move around.
The highlighted (yellow) lattice is the only part of the animation that has key frames. All of the other lattices and bones "follow" that lattice's animation through the use of constraints and "parenting". So the "engine" is actually the axle which is totally reversed from real life.
BTW the bones going more or less directly downwards, link to a point 100 metres below the model. This is a trick described in Paul Hobbs tutorial and, I believe, was an original idea by Bill Fock. It makes an attached mesh move through a very small arc on a very large circle and helps piston movement on sloped cylinders. This would not be needed for Zeldaboy's model.
It's fun just watching all the bits move around.