MSPhysics 1.0.3 (16 October 2017)

Anton_S

Hello, Nicolas,

To get local velocity, along the body's Y-axis, you got to transform the global velocity relative to the body first, then get the Y component:

loc_vel = this.get_velocity.transform(this.get_normal_matrix.inverse)
vy = loc_vel.y

Regards,
Anton

Anton_S

Faust, I will ckeck out that cloth thingy soon.

faust07

Hi, Anton,
first test of a (cloth-) mesh with your MSPhysics API self connect script.
Unfortunately, each node joins only one rod. What am I doing wrong?

Connect_test_01.skp

Anton_S

Okay, faust.

Your script for connecting bodies attempts to connnect multiple bodies to the same joint. That's how it is in the user interface of MSPhysics, but behind the scenes a new joint instance is added for each constraint. So here is the script to have:

onTick {
  if frame == 1
    this.touching_bodies(true).each { |body|
      next if body.group.name != 'capsule'
      joint = MSPhysics;;BallAndSocket.new(this.world, this, this.get_matrix, this.group)
      joint.connect(body)
    }
  end
}

Paste it into one knot, and assign it to all knots, using the Assign Script to All With Name button.

That said, this is a very inefficient way of creating cloth, not to mention that you also have to create faces and then reposition vertices and map the UVs of textures (if any).

I already got my own, more efficient, version of cloth working, like 3 years ago. But it's not perfect. Here is the demo updated and refined for the current version of MSPhysics:

https://youtu.be/itEMzqpdqy4

cristyan

Hello ! There is a script or another way that maintains the same distance between objects attached on CurvySlider , as a rollercoaster ? Thank you !

faust07

Thanks, Anton,
Your code works perfectly. For genuine cloth simulation this is, of course, too cumbersome. For me, it is a good practice to learn a little bit of good script again. In addition, the example shows the almost unlimited possibilities of MSPhysics.

and this happens after 1.800 frames

Anton_S

Oops, the get_normal_matrix should be normal_matrix

Also, to quote other people, use the double-quote button or put them in quote tags surrounded with square brackets. And posting the whole video on the error isn't necessary either. Just post a message that is reported.

SynSuka3D

==============================

To get local velocity, along the body's Y-axis, you got to transform the global velocity relative to the body first, then get the Y component:
CODE: SELECT ALL
loc_vel = this.get_velocity.transform(this.get_normal_matrix.inverse)
vy = loc_vel.y

Regards,
Anton

===================
problem!!!!!!

ecati

This gears is not spinning properly. What would be the reason?

dişli.jpg

dişli.skp

ecati

Hi, Anton
Will you take a look at this file at a time when you are not busy?

makine.skp

Anton_S

Hello, Ecati,

For the first one, try setting material thickness of simulation tab, in the MSPhysics UI, to zero. It will improve the behavior by a bit. But because the gears are too small, the collision intersections aren't quite proper. You could increase world scale, say to 40, which should result in an improved behavior, but it will unfortunately result in a crash. I will try to fix that scaling bug before releasing 1.0.0.

For the second one, you can increase update rate, to say 4, and/or reduce update timestep, to say 1/120. The smaller the update timestep is, the more accurate the simulation is. The smaller update timestep should prevent collisions from deteriorating. Both of the settings can be adjusted through the Simulation tab of the MSPhysics UI dialog. After you do these, increasing the motor speed should have things running properly.

Nice examples by the way. I'm stunned with your improved MSPhysics skills.

Regards,
Anton

ecati

Is it possible to do servo controls via the msphysics API without writing a script?

Anton_S

It depends on how complex you want the controller to be. The simplest one is the slider controller. You can generate it by pressing the generate slider button in joint UI. Others are controlling with key, like key('f') as noted in some prior post. You can also write a function of time dirctly into the cpntroller, like: t = world.time; cos(t)*5 There are many controllers you can write without relying on the MSPhysics scripting API.

Wolfy_71

I'm really enjoying MSPhysics plug-in and have been following Sam Ketner's very insightful tutorials on Youtube. I'm wondering if there is a manual easily available, so I can bone up on some more stuff. More pressingly, I'm wondering how to attach one hinge with a bar (which appears to be in a fixed point) on a bar attached to another hinge... so that it is freely movable. I'm trying to draw an umbrella-like hinge at the moment and I'm stuck.

ecati

Hi, Anton,
I made this file by taking advantage of the Planned Steps.skp file you have prepared. I want the movement to begin when the space key is pressed and continue and stop until the space key is pressed again.

makine_servo.skp

Anton_S

@ecati said:

I made this file by taking advantage of the Planned Steps.skp file you have prepared. I want the movement to begin when the space key is pressed and continue and stop until the space key is pressed again.

This command will be available in MSPhysics 1.0.0. Basically you will utilize the toggle_key('space') command. It will be released soon.

Anton_S

@wolfy_71 said:

I'm really enjoying MSPhysics plug-in and have been following Sam Ketner's very insightful tutorials on Youtube. I'm wondering if there is a manual easily available, so I can bone up on some more stuff. More pressingly, I'm wondering how to attach one hinge with a bar (which appears to be in a fixed point) on a bar attached to another hinge... so that it is freely movable. I'm trying to draw an umbrella-like hinge at the moment and I'm stuck.

To create movable hinges, you have to create them within the context of a desired parent group/component. Then connect it to the desired child group/component (using the MSPhysics Joint Connection Tool). That way the parent group will move and the connected child group will move relative to the parent group, while rotating around the hinge axis, which will also be relative to the parent group.

SynSuka3D

Hello, I would like to create text that does not of the world of the !! Example: the objects far from the center of the axis!

And I would like to create lines, shapes, points !! A radar...

Anton_S

SynSuka3D, you should explore SketchyPhysics models at 3DWarehouse on that and then write a similar script for what you want. For instance, a Radar by Mr. K: https://3dwarehouse.sketchup.com/model/c8b415a0bbb385b87e683c55e87c0665/Radar-3

SynSuka3D

Thanks Anton_S,
But I would like a radar of this style !! Of my model Sketchyphysics for MsPhysics!

https://3dwarehouse.sketchup.com/model/dc1774c9431e40bad9689dffd6e75da7/Avion-2-sp-No-Gyro

Avion+02.skp

MSPhysics 1.0.3 (16 October 2017)

==============================

Regards, Anton

Regards,
Anton