MSPhysics 1.0.3 (16 October 2017)

surfmike

Is it possible to create/script a hall sensor functionality detecting magnetism strength and direction?

TDahl

I recently completed a detailed (nearly 18 minutes long) video animation that includes two sequences created with MSPhysics - the first at 8:00 into the video, the second at 14:00. The subject of the video is a description of some real space hardware, the surface sampler or "scoop" from the Viking '75 Mars lander of 40 years ago.

The first MSPhysics sequence uses about 250 short thin strips to represent a flexible cable winding and unwinding. The second sequence contains about 5500 little marbles to represent soil particles being dug by the Viking lander's sampler backhoe or shovel. (The remainder of the animations were created with the Animator beta extension.)

Thank you for such a nice MSPhysics extension, Anton!
https://youtu.be/4c5o6jaJOuI

faust07

Absolutely great!

Oxer

Incredible work, congratulations!!

Anton_S

Tom Dahl, I did see your viking lander video - very inspiring and educational! I also commented at your Sketchup Community thread. Nice work!

Aside from that, I have logged all the crash reports, issues, and feature requests reported by you and many others. I have learned many things from the feedback. MSPhysics will be rewritten, with tutorials this time...

rick149

Tom Dahl, I cannot find superlatives adequate to describe your historic video that so effectively diplays the ingenious viking sampler for us mere mortals. thank you. thank you.. more please..

pabloarias

@anton_s said:

Tom Dahl, I did see your viking lander video - very inspiring and educational! I also commented at your Sketchup Community thread. Nice work!

Aside from that, I have logged all the crash reports, issues, and feature requests reported by you and many others. I have learned many things from the feedback. MSPhysics will be rewritten, with tutorials this time...

I really like your Nasa's Viking project videos Tom. Great job.

Anton, don't you forget the plugin for soft and cloth surfaces. I'd like to test it and if you want I can help you to debug it.

charlessowers

Hello, I am working on a project to create a long torsion wave as an interactive artwork on a bridge. I have been able to simulate the wave behavior in MSPhysics. I am psyched for that but now I would like to simulate the interaction which will be driven by sensors controlling motors that will pull the pendulum top in towards the bridge when a person breaks an IR beam. I'd like to be able to click on one of the pendulums and have it move in at a user defined rate and then release and swing freely. Is there a way to do this? I have seen something in the API called onLButtonDown but also best_picked in the sketchup API but I am not really a programmer and am not sure how to put these together if they are even appropriate. Might someone be able to help? or at least suggest an approach?

BrigdeHandRailPendulum5.skp

Anton_S

Hello, charlessowers,

I'm not quite sure what you're trying to achieve. Using a simple pick and drag tool may help. Just hold the shift key when dragging the IR beams.

If in case you want to do something else, perhaps an onClick even will help. For that you will have to utilize an onClick event for all beams, which will do the desired thing when a beam is clicked. (And of course, to write the same script to all beams you can write script to one beam and make use of the "assign script to all with name" button).

Anton

charlessowers

Hello Anton,

Thanks for the plugin and thank you for considering my question.

An onClick sounds like a great possibility, but I am not sure how to use it. I tried this script applied to a picket...

# Triggered when simulation starts
onStart {
    @force = 45
}

# triggered when body is clicked
onClick {|point|
  fx =  @force
  this.add_force(fx, 0, 0)
}

But it didn't work. maybe it needs time for the force to be applied after the click? Maybe it should be a torque? Maybe it should set the start angle of the spring hinge? Not sure if onClick always applies to the thing clicked (this)?

Anton_S

Charles,

You got the idea right, but the force you apply must be applied as a point force. Doing so will also, generate torque as you want. For the point, you can either apply force at clicked location or at a particular point such as pole's origin + some shift in the up direction...

Here is the script for applying at point force:

# Triggered when simulation starts
onStart {
  @impx = 45 * simulation.update_timestep_inv
}

# triggered when body is clicked
onClick { |point|
  this.add_point_force(point, Geom;;Vector3d.new(@impx, 0, 0))
  # Or point could be a custom point
  #tra = this.normal_matrix
  #point = tra.origin + AMS;;Geometry.scale_vector(tra.zaxis, 100)
  #this.add_point_force(point, AMS;;Geometry.scale_vector(tra.xaxis, @impx))
}

Note that in the simulation tab, you will have to enable the game mode option, which will disable the pick & drag tool, to prevent it from interfering.

Then, the script is then supposed to be assigned to every pole thingy in your model. As mentioned before you can do this by using the "assign script to all with name" button (assuming that all pole thingies have the same name).

Anton

charlessowers

Thanks Anton! That does the trick. Is there a way to re-enable orbit control (middle mouse button) and zoom (mouse wheel) while in game mode?

Anton_S

Charles,

For now, there isn't a way other than modifying the simulation code, so that it only disables the pick & drag and not the user input. I may need to add a Ruby function for that in the future versions.

Anton

Kevinberger

Hello nice article,

one question. Is it possible to create an outstanding moving camera crane while using MS Physics in SketchUp?

faust07

Nothing could be easier. Examples of camera simulations with MSphysics can be found here: http://sketchucation.com/forums/viewtopic.php?f=323&t=68975
You can connect the moving parts of the crane with MSPhysics Joints, place the crane on rails and control everything with sliders, keyboard or scripts.

Mike Amos

I may be a little slow of late but, can someone suggest how I can make a table cloth or bedding in simple terms? Sorry to bug you folks.

faust07

@ Mike: Anton_S is currently working on an easy-to-use plugin for this purpose.

mickaellemickael

Hello everyone
I'm new here. I found this plugin yesterday and try to use it to simulate the equilibrium of a wooden product I'm designing.
The structure is in wood, and it supports heavy objects by their side with big screws (so they are not resting on the wood structure). If I group all of these or make a component, it feels like the mass of these heavy objects is lost, and so playing the simulation gives very strange (and false ) results, as the structure doesn't fall on the ground as it should.

The fact is I don't understand how to keep the different masses AND attach the objects between them. I tried with the fixed joint but it fixes everything and nothing at all moves

Could you help me please ?
Thanks

Anton_S

Hello mickaellemickael,

The collision generated for objects is convex and thus doesn't reflect the real object. Your group must be made up of convex items for the mass to be reflected. You can also assign the mass manually, via the MSPhysics UI by changing the Mass Control mode to Mass and assigning the right mass (in kg).
Mass Control.png

You can enable collision wireframe for all objects in simulation, which can be found in Debug Draw section of the simulation tab in the MSPhysics UI. This draws the actual collision wireframe generated for the object. You may have to divide the object into convex sub-groups for the most realistic effects (assuming the top-level group is assigned a compound collision).
Collision Wirefreame.png

In compound collision (which is assigned to objects by default), all sub-groups and sub-components are treated as convex sub-collisions.

By meaning convex collision, the collision is wrapped around a shape. Here is an image for example: http://newtondynamics.com/wiki/images/2/24/Convex_shape.jpg

So with compound collision, you can have many convex collisions clumped together to form a complex dynamic collision.

Anton

cgltkn

Hi Anton,

I understand your approach on the unreliable nature of "compound from cd" shape. However without it, there isn't a better way to make a front wheels of a car. You can't try to make sub groups of a car mesh, it's a lot of work and "compound" doesn't work as an alternative because in collision wireframe body of the car interferes with the rotating tires.

Can't you at least leave compound from cd in the selection list with a warning? It would be better if any demanding users should be able to use it.

Best regards.