MSPhysics 1.0.3 (16 October 2017)

Anton_S

Ecati, that's too much joints and collisions. MSPhysics can't handle that much, especially that joints are weak and unstable when are linked into chains. If your intent is to simply play the bike, you should take an approach of making games, where only the essential parts are made to work. All you need is the frame (set to convex hull) and two wheels (set to to sphere shape). The rest could be removed or placed within the frame and set to ignore. Then a few joints, one for steering and two for motors, would guarantee you a fast working bike. But, if your approach is to simulate how the bike works, with all the moving parts, then MSPhysics is definitely not a plugin for that.

ecati

Hi, Anton,
My purpose is to move the bike by chain, just like it is in a real bicycle. If I understand correctly, it is not possible to do this with MSPhysics. Is it true?

Anton_S

Ecati,you understood it correctly.

cristyan

Hello !! Ecati try group the chain in another way something like like the file here ..and when you run MSPhsics delete guides( Edit>delete guides)this will make it run faster ..make a copy of your file first ...

chain_bicycle.skp

ecati

Hi, Cristyan,
I applied your suggestions. But there has not been any improvement.

bisiklet_forum.skp

ecati

The model in the attached file hangs and disintegrates after a period of working properly. What would be the reason?

tren.skp

faust07

Hi ecati,
Interesting model with inverse kinematics.
Now it should work longer.
The main problem was the position of the external joints too far from the center of gravity of the associated components.
This has led to instability, too much friction and breakage of some joints.
In order to improve the performance, it is also useful to set as many internal groups as "Ignore" as possible.
This has to be tested in detail. I have resolved some group nesting up to a meaningful depth.

tren_02SUp16.skp

ecati

Thank you very much for your time and information.

topdeadcentre

Hello there, I am loving MSPhysics, although I am finding limited tutorials and have gotten stuck trying to make a basic monitor arm (robot arm pretty much) I understand the tools yet I am struggling to understand how to get 2 or more servos on one arm. For instance, I group my first arm to a servo, yet I cannot use the joint connection tool further into that group onto the next arm for it to stay relative to the first arm. below is a file submitted which works perfectly but I am trying to understand how he did this, is it obtainable without scripting?

here is a working example of what I want to know: https://3dwarehouse.sketchup.com/model/c3eabd528e13297ddf6d65aa66a5c53/Robot-arm

thank you!

Anton_S

Hello, Jon,

The concept of joints in MSPhysics is similar to SketchyPhysics. If you check out YouTube tutorials on joints in SketchyPhysics, same things could be accomplished through MSPhysics in a similar way, just through using MSPhysics tools.

So, to create a joint that is relative to another group, first, all arms should be top level groups. Then, within the context of each arm, add a joint and connect it to the next arm. Here, I made a quick tutorial on adding joints to a robot arm:

Youtube Video

For the tutorial, I used the latest version of MSPhysics, which I haven't released yet but the way of doing it is not any different from the current version.

I know MSPhysics lacks the tutorials on many of its features, but that's because it is still under development. Making a tutorial with an unstable version, would make it obsolete when a better, stable, and more user-friendly version of MSPhysics is released; therefore, I want to finish the stable version first before proceeding to tutorials.

Best regards,
Anton

topdeadcentre

Amazing reply, thank you so much!

juju

@Anton_S cough cloth cough simulator clears throat

Anton_S

Hi, Juju! I started working on Drape a few weeks ago. I first wanted to use NewtonDynamics for cloth but then figured to write my own specific purpose physics engine instead. I already got the cloth working. All I need to do now is add contacts and the user interface. Adding the collision contacts is the hardest part, but I'm researching that.

Anton_S

Announcing MSPhysics 1.0.0!

This version comes with a significant amount of improvements and a few new features. Main feature is a custom automated transitioning of scenes, which can transition forward, backward, and loop. Here is a model demonstrating it:
Planned Steps.skp
A detailed list of other features and bug fixes can be found here: http://www.rubydoc.info/github/AntonSynytsia/MSPhysics/file/RubyExtension/MSPhysics/CHANGELOG.md

This requires installing AMS Library version 3.5.0, which is referenced in first post. If you received development versions of AMS Library, you must upgrade to the latest one.

Also, you no longer have to bother removing original versions as the overwriting should work fine now.

I have removed geared joints feature until the next release, as it was the only thing that preventing me from releasing this version.

And one more thing, models creating with prior MSPhysics version might work differently/be incompatible with this version. Make sure to update your models' physics properties and scripts if necessary.

faust07

Hi Anton, thanks for the great improvements!
Keyboard navigation and scenes animation are great new features and work very well. It would be great if the scenes excluded from the SketchUp animation are also excluded from MSPhysics (e.g. EDIT scenes or the like).

For rendering single images, I usually set 30 frames per second. All previous scripts, for example for programmed emitters, refer to this in terms of lifetime. What image rate does MSPhysics use for internal calculation and export, if I want to convert the previous lifetime settings in seconds?

Adjusting the settings and rewriting the scripts will probably take me a while longer. First small test example see at post "MSPhysics Tests and Questions".

ecati

How to convert a model created with MSPhysics 0.9.9 to 1.0.0.

Anton_S

Faust: I fixed it. Update to 1.0.1.

Ecati: It depends on a model. If your model is working properly, then there is nothing necessary to update; otherwise, adjust the properties of joints, body properties, like emitters, and scripts (if any). If you have trouble doing so, post a model in "MSPhysics Tests and Questions" thread if you need help.

rick149

Camera Follow Tool: Can I hide the highlighted selection?

The Camera Follow and Target tools work by right clicking the required entity as the target to follow during the simulation.

The selected item is highlighted in a blue box.

Is there any way to suppress the highlighting while the simulation is running?

Anton_S

Left-click on the sky/background to suppress the highlighting. You can't unfortunately hide the group from the menu though. I should've thought of adding this command.

rick149

thanks Anton, that works fine
MSPhysics is truly awesome

i am keen to learn more about scripts